A novel 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative is represented by following Formula (1):

1. Field of the Invention
The present invention relates to an 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative and a production process therefor, as well as to production processes for a N-substituted-3-aminomethyltetrahydrofuran-2-one derivative, for an 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative and for an 3-aminomethyltetrahydrofuran-2-one derivative using the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative as a starting material.
2. Description of the Related Art
To produce an analogous compound to 3-aminomethyltetrahydrofuran-2-one, Japanese Unexamined Patent Application Publication No. 7-60131 discloses a process in which 3-methylenetetrahydro-2-(3H)-furanone is allowed to react with diethylamine in the presence of an inorganic compound and thereby yields a N,N-diethyl-aminomethyltetrahydrofuran-2-one. However, the prepared N,N-diethyl-aminomethyltetrahydrofuran-2-one cannot yield 3-aminomethyltetrahydrofuran-2-one by a simple reaction, which 3-aminomethyltetrahydrofuran-2-one is practically used as a pharmaceutical intermediate.
Accordingly, an object of the present invention is to provide a novel 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative that is useful for the preparation of an 3-aminomethyltetrahydrofuran-2-one derivative, as well as to provide a production process for the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative.
Another object of the present invention is to provide production processes for a N-substituted-3-aminomethyltetrahydrofuran-2-one derivative and for an 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative, which are useful for the preparation of such an 3-aminomethyltetrahydrofuran-2-one derivative.
A further object of the present invention is to provide a process for efficiently producing an 3-aminomethyltetrahydrofuran-2-one derivative by a simple reaction.
After intensive investigations to achieve the above objects, the present inventors have found that such an 3-aminomethyltetrahydrofuran-2-one derivative can easily be obtained from a novel 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative. The present invention has been accomplished based on these findings.
Specifically, the present invention provides, in an aspect, an 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by following Formula (1):
wherein R1, R2 and R3 are the same or different and are each a hydrogen atom or an aliphatic hydrocarbon group; and R4 and R5 are the same or different and are each a hydrogen atom or an arylmethyl group which may have a substituent, where at least one of R4 and R5 is an arylmethyl group which may have a substituent.
In another aspect, the present invention provides a process for producing the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1). The process includes the step of subjecting an 3-acetyltetrahydrofuran-2-one derivative represented by following Formula (2):
wherein R1, R2 and R3 are the same or different and are each a hydrogen atom or an aliphatic hydrocarbon group, to aminomethylation by a reaction with formaldehyde or a polymer thereof and a primary or secondary amine represented by following Formula (3):
wherein R4 and R5are the same or different and are each a hydrogen atom or an arylmethyl group which may have a substituent, where at least one of R4 and R5 is an arylmethyl group which may have a substituent.
The present invention provides, in a further aspect, a process for producing a N-substituted-3-aminomethyltetrahydrofuran-2-one derivative. The process includes the step of deacetylating the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) by a reaction with a base to thereby yield a N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by following Formula (4):
wherein R1, R2, R3 R4 and R5 have the same meanings as defined above.
In yet another aspect, the present invention provides a process for producing an 3-aminomethyltetrahydrofuran-2-one derivative. The process includes the steps of deacetylating the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) by a reaction with a base to thereby yield a N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4), and subjecting this compound to hydrogenolysis to thereby yield an 3-aminomethyltetrahydrofuran-2-one derivative represented by following Formula (5):
wherein R1, R2 and R3 have the same meanings as defined above.
In another aspect, the present invention provides a process for producing an 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative. The process includes the step of subjecting the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) to hydrogenolysis to thereby yield an 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by following Formula (6):
wherein R1, R2 and R3 have the same meanings as defined above.
Yet another aspect, the present invention provides a process for producing the 3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (5). The process includes the steps of subjecting the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) to hydrogenolysis to thereby yield the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (6), and deacetylating the resulting compound by a reaction with a base.
The present invention can easily yield novel 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivatives.
The present invention can easily yield N-substituted-3-aminomethyltetrahydrofuran-2-one derivatives and 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivatives, which are useful for the preparation of the 3-aminomethyltetrahydrofuran-2-one derivatives.
In addition and advantageously, the present invention can efficiently yield 3-aminomethyltetrahydrofuran-2-one derivatives by a simple reaction.
3-Acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one Derivatives and Production Thereof
In the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivatives represented by Formula (1), the substituents R1, R2 and R3 are the same or different and are each a hydrogen atom or an aliphatic hydrocarbon group.
Such aliphatic hydrocarbon groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, s-butyl, t-butyl, pentyl, hexyl, decyl, dodecyl, andotheralkyl groups each having from about 1 to about 10, and preferably from about 1 to about 4, carbon atoms; vinyl, allyl, 1-butenyl, and other alkenyl groups each having from about 2 to about 10, and preferably from about 2 to about 4, carbon atoms; ethynyl, propynyl, and other alkynyl groups each having from about 2 to about 10, and preferably from about 2 to about 4, carbon atoms.
In Formula (1), the substituents R4 and R5 are the same or different and are each a hydrogen atom or an arylmethyl group which may have a substituent, where at least one of R4 and R5 is an arylmethyl group which may have a substituent. The substituent may be substituted on a carbon atom of whichever of the aryl moiety and the methyl moiety of the arylmethyl group. Such aryl groups include aromatic carbocyclic groups and aromatic heterocyclic groups.
Such aromatic carbocyclic groups include, but are not limited to, phenyl, naphthyl, and other aromatic carbocyclic groups each having from about 6 to about 20, and preferably from about 6 to about 10, carbon atoms. The aromatic heterocyclic groups include, for example, pyridyl group.
Substituents which may be substituted on the aryl moiety of the arylmethyl group include, but are not limited to, halogen atoms (e.g., fluorine, chlorine and bromine atoms), oxo group, hydroxyl group, substituted oxy groups (e.g., methoxy group and other alkoxy groups; aryloxy groups; aralkyloxy groups; and acyloxy groups), carboxyl group, substituted oxycarbonyl groups, substituted or unsubstituted carbamoyl groups, cyano group, nitro group, substituted or unsubstituted amino groups, and alkyl groups (e.g., methyl, ethyl, propyl, isopropyl, and other C1-C4 alkyl groups)
Substituents which may be substituted on a carbon atom of the methyl moiety of the arylmethyl group include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, and other alkyl groups (preferably, alkyl groups each having from 1 to 4 carbon atoms), the aforementioned aryl groups such as phenyl, naphthyl, pyridyl, and other aromatic carbocyclic groups or aromatic heterocyclic groups which may have a substituent.
In the arylmethyl group, a substituent on the methyl moiety may be combined with the aryl moiety or with a substituent on the aryl moiety to form a ring.
Examples of the arylmethyl group are benzyl, p-chlorobenzyl, p-bromobenzyl, o-nitrobenzyl, p-nitrobenzyl, p-cyanobenzyl, 3,4-dimethoxybenzyl, xcex1-phenylethyl, diphenylmethyl, bis (p-methoxyphenyl)methyl, triphenylmethyl, (p-methoxyphenyl)diphenylmethyl, diphenyl-4-pyridylmethyl, 2-pyridyl-N-oxide, and 5-dibenzosuberyl groups.
The 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivativerepresentedbyFormula (1) can be obtained by allowing an 3-acetyltetrahydrofuran-2-one derivative represented by Formula (2) to react with formaldehyde or a polymer thereof and a primary or secondary amine represented by Formula (3) and thereby introducing a N-substituted aminomethyl group into the 3-position of the 3-acetyltetrahydrofuran-2-one derivative represented by Formula (2).
The substituents R1, R2, R3, R4 and R5 in Formula (2) and (3) include the same groups as mentioned above.
As formaldehyde, pure formaldehyde may be used, but an aqueous solution of formaldehyde (formalin) having a concentration of from about 30% to 50% by weight, and preferably from about 35% to 45% by weight, is advantageously used. The formaldehyde may be formed in a reaction system. Polymers of formaldehyde include, for example, paraformaldehyde and other low molecular weight polyoxymethylenes. The amount of the formaldehyde or a polymer thereof is, as formaldehyde, from about 1 to about 3 moles and preferably from about 1.1 to about 2 moles relative to 1 mole of the substrate 3-acetyltetrahydrofuran-2-one derivative.
A reaction is performed in the presence of, or in the absence of, a solvent. The solvent is not specifically limited, as long as it does not adversely affect the reaction. Such solvents include, but are not limited to, methanol, ethanol, propanol, t-butyl alcohol, and other alcohols; chloroform, dichloromethane, 1,2-dichloroethane, and other halogenated hydrocarbons; benzene and other aromatic hydrocarbons; hexane, heptane, octane, and other aliphatic hydrocarbons; cyclohexane and other alicyclic hydrocarbons; N,N-dimethylformamide, N,N-dimethylacetamide, and other amides; acetonitrile, propionitrile, benzonitrile, and other nitriles; diethyl ether, t-butylmethyl ether, tetrahydrofuran, and other chain or cyclic ethers; ethyl acetate and other esters; acetic acid and other organic acids; and water. Preferred solvents are water; and methanol, ethanol, propanol, and other alcohols, of which water is typically preferred. Each of these solvents can be used alone or in combination.
A reaction temperature can appropriately be set depending on the type of the substrate and other factors and is, for example, from about 10xc2x0 C. to about 100xc2x0 C., and preferably from about 20xc2x0 C. to about 50xc2x0 C. The reaction smoothly proceeds at around room temperature.
The reaction may be performed at ambient or atmospheric pressure or under a pressure (under a load) in a conventional system such as batch system, semi-batch system or continuous system.
After the completion of the reaction, reaction products can be separated and purified by, for example, filtration, concentration, distillation, extraction, crystallization, recrystallization, adsorption, column chromatography, and other separation means or combinations of these separation means.
The N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4) can be prepared by deacetylating the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) by a reaction with a base.
Such bases for use in the reaction include, but are not limited to, sodium carbonate, potassium carbonate, and other alkali metal carbonates; sodium hydrogencarbonate, potassium hydrogencarbonate, and other alkali metal hydrogencarbonates; sodium hydroxide, potassium hydroxide, and other alkali metal hydroxides; magnesium carbonate, calcium carbonate, and other alkaline earth metal carbonates; magnesium hydrogencarbonate, calcium hydrogencarbonate, and other alkaline earth metal hydrogencarbonates; magnesium hydroxide, calcium hydroxide, and other alkaline earth metal hydroxides; and other inorganic bases. Each of these bases can be used alone or in combination. The amount of the base is from about 0.5 to about 4 moles, and preferably from about 1 to about 2 moles, relative to 1 mole of the substrate 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative.
The reaction is generally performed in the presence of a solvent. Such solvents are not specifically limited as long as they do not adversely affect the reaction and include the solvents exemplified in the production of the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative. Preferred solvents in this reaction are water; methanol, ethanol, propanol, isopropanol, butanol, and other alcohols; diethyl ether, t-butylmethyl ether, and other ethers. The amount of the solvent is, for example, from about 2 to about 30 parts by weight, and preferably from about 3 to about 20 parts by weight, relative to 1 part by weight of the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative.
To perform the reaction in a shorter time, a phase transfer catalyst may be added to the reaction system. Such phase transfer catalysts include, but are not limited to, tetraethylammonium chloride, tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium bromide, tetrabutylammonium iodide, tetraethylammonium hydrogensulfate, tetrabutylammonium hydroxide, tetraoctylammonium chloride, trimethylbenzylammonium chloride, triethylbenzylammonium chloride, tributylbenzylammonium chloride, tributylbenzylammonium bromide, trioctylbenzylammonium chloride, cetyldimethylbenzylammonium chloride, tetrabutylphosphonium chloride, tetrabutylphosphonium bromide, and other conventional phase transfer catalysts. Among them, cetyldimethylbenzylammonium chloride and triethylbenzylammonium chloride are preferred. The amount of the phase transfer catalyst is, for example, from about 0.01 to about 0.3 mole, and preferably from about 0.05 to about 0.1 mole, relative to 1 mole of the substrate 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative.
A reaction temperature can appropriately be set depending on the type of the substrate and other factors and is, for example, from about 0xc2x0 C. to about 50xc2x0 C., and preferably from about 0xc2x0 C. to about 10xc2x0 C. The reaction can be performed in a conventional system such as batch system, semi-batch system or continuous system.
After the completion of the reaction, reaction products can be separated and purified by, for example, filtration, concentration, distillation, extraction, crystallization, recrystallization, adsorption, column chromatography, and other separation means or combinations of these separation means.
The 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (6) can be obtained by subjecting the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) to hydrogenolysis (hydrocracking).
The hydrogenolysis is generally performed by bringing the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative into contact with hydrogen in a solvent in the presence of a hydrogenolysis catalyst. Such hydrogenolysis catalysts include any conventional hydrogenolysis catalysts, of which a palladium-carbon (activated carbon) catalyst is preferred.
In the palladium-carbon (activated carbon) catalyst, the activated carbon is not specifically limited and includes any activated carbon derived from vegetable materials, mineral materials, polymer materials and other materials by conventional techniques such as gas activation and chemical activation. The activated carbon has a specific surface area of, for example, from about500 to about4000 m2/g and preferably from about 700 to about 4000 m2/g. The amount of palladium on the activated carbon is, for example, from about 1% to about 30% by weight, and preferably from about 3% to about 20% by weight, relative to the weight of the activated carbon.
The amount of the palladium-carbon catalyst is, for example, from about 0.1% to about 20% by weight, and preferably from about 1% to about 10% by weight, relative to the weight of the substrate 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative.
Hydrogen for use in the hydrogenolysis is not specifically limited and includes pure hydrogen and hydrogen diluted with an inert gas such as nitrogen, argon or helium gas. A gas phase component can be dissolved in a liquid phase by any technique, as long as the gas phase component is sufficiently dissolved in the liquid phase. For example, the gas phase component may be dissolved by gas-liquid contact alone or by blowing a gas containing hydrogen into the liquid phase. Instead of hydrogen, HCOONH4, HCOONH (C2H5)3, NaH2PO2, NH2NH2 and other hydrogen sources can be used.
The amount of hydrogen can appropriately be set depending on the type of the substrate and other factors and is generally molar excess to the substrate.
Solvents for use in this reaction are not specifically limited as long as they do not adversely affect the reaction and can solve reaction components. Such solvents include, for example, methanol, ethanol, propanol, isopropanol, and other alcohols. The amount of the solvent is generally from about 3 times to about 50 times, and preferably from about 5 times to about 10 times relative to the amount of the substrate.
A reaction temperature is not specifically limited and is preferably from about 10xc2x0 C. to about 30xc2x0 C.
The reaction may be performed at atmospheric pressure or under a pressure (under a load). When the reaction is performed under a pressure, the pressure is generally from about 0.1 to about 10 MPa, and preferably from about 0.1 to about 1 MPa. The reaction can be performed in a conventional system such as batch system, semi-batch system or continuous system.
After the completion of the reaction, reaction products can be separated and purified by, for example, filtration, concentration, distillation, extraction, crystallization, recrystallization, adsorption, column chromatography, and other separation means or combinations of these separation means.
Using the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1) as a starting material, the 3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (5) can be prepared by either (i) a process via the production of the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4) or (ii) a process via the production of the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (6).
The process (i) via the production of the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4) includes the steps of (A) yielding the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4) from the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1), and (B) subjecting the resulting compound to hydrogenolysis.
The production process for the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative can be applied as the step (A) of the process (i). In the step (B) of the process (i), the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative as a substrate is subjected to hydrogenolysis in a similar manner as in the production process for the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative.
The process (ii) via the production of the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (6) includes the steps of (A) yielding the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (6) from the 3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (1), and (B) deacetylating the resulting compound by a reaction with a base.
As the step (A) of the process (ii), the production process for the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative can be applied. In the step (B) of the process (ii), the 3-acetyl-3-aminomethyltetrahydrofuran-2-one derivative as a substrate is deacetylated by a reaction with a base in a similar manner as in the production process for the N-substituted-3-aminomethyltetrahydrofuran-2-one derivative represented by Formula (4).

3-acetyl-N-substituted-3-aminomethyltetrahydrofuran-2-one derivative and production process therefor

Abstract: wherein R1, R2 and R3 are the same or different and are each a hydrogen atom or an aliphatic hydrocarbon group; and R4 and R5 are the same or different and are each a hydrogen atom or an arylmethyl group which may have a substituent, where at least one of R4 and R5 is an arylmethyl group which may have a substituent. This compound can be prepared by aminomethylating an 3-acetyltetrahydrofuran-2-one derivative represented by following Formula (2):

Abstract: wherein R1, R2 and R3 have the same meanings as above, by a reaction with formaldehyde or a polymer thereof and a primary or secondary amine represented by following Formula (3):

Abstract: wherein R4 and R5 have the same meanings as above.


An optical information record carrier consists of upper and lower optical disks maintained separate from each other by an annular spacer juxtaposed to the outer periphery of the surfaces of the optical disks facing one another. The spacer is glued to the optical disks to produce a carrier with spaced optical disks and an air gap between the disks interior of the annular spacer. To assure sufficient adhesive will remain between the spacer surfaces and their facing optical disk surfaces as these components are squeezed together during the assembly process, one of the spacer of the optical disks is provided with a projection or recess.

The present invention relates to an optical information record carrier of the type comprising upper and lower optical disks, each with an optical recording surface facing the other, and an annular spacer located along the outer periphery of the upper and lower recording surfaces an air gap thus being formed between the facing recording surfaces interior of the annular spacer.
FIG. 1 illustrates a conventional optical information record carrier 1 of the type to which the present invention obtains. The upper and lower optical disks of the carrier are designated by the reference letter a. An optical information record layer 2 is provided on each of the facing optical recording surfaces. An air gap is maintained between the optical disks a by an annular spacer b located about the outer periphery of the optical disks. The spacer is fixed to the disks a at the location shown in FIG. 1 by an adhesive 3.
The conventional process for assembling the carrier illustrated in FIG. 1 includes the following steps:
1. An optical disk (a) which is to form the lower disk in the carrier 1 is set on a support jig so that its information recording layer 2 faces upwardly. PA0 2. An adhesive 3 is supplied to the outer peripheral portion of the optical disk (a) in the support jig. PA0 3. The spacer (b) is then positioned on the adhesive 3 covering the peripheral portion of the optical disk (a). PA0 4. The adhesive 3 is thereafter also applied to the top of the spacer (b). PA0 5. The other optical disk (a), which is to form the upper disk, is positioned so that its peripheral portion is on the adhesive 3 covering the top of the spacer (b) and so that the information recording layer 2 of the upper optical disk faces downwardly. PA0 6. A weight is then put on the upper optical disk (a) so that the sandwich structure of two optical disks and a spacer therebetween is squeezed together until the adhesive 3 hardens.
A very serious problem with such a conventional structure may be explained as follows.
Before the adhesive 3 hardens, it is so soft that it tends to be pushed out of the area between the spacer and optical disks by the pressure of the weight. Therefore, if the adjoining surfaces of the optical disks (a) and the spacer (b) are completely flat, almost all of the adhesive 3 between these adjoining surfaces is pushed out, leaving at most only several microns of adhesive between the adjoining thickness of surfaces of each optical disk (a) and the spacer (b). This results in very poor adhesion between the disks and spacer, causing the disks to easily separate from the spacer.
If each optical disk (a) and/or the spacer (b) has a warp which cannot be corrected by the pressure of the weight, a gap will exist between the disk and the spacer so that a relatively thick layer of adhesive 3 will exist in the gap while at best only several microns of adhesive will exist between the disks and spacer at all other locations about the outer periphery of the disks. When the thickness of the adhesive 3 is only several microns, its adhesion power decreases markedly thus making it likely that the optical disks (a) and the spacer (b) will separate, even if a relatively thick layer of adhesive exists only in the gap produced by the warped section of the disk and/or the spacer.

Optical information carrier having a spacer securely bonded between disks by adhesive


Provided are a silicone rubber sponge that forms an elastic layer of a pressure roller of an image-forming apparatus, and that has a high mechanical strength so as to be used in a high-speed image-forming apparatus or a color image-forming apparatus, and a rubber-covered roller including the silicone rubber sponge. The silicone rubber sponge is produced by mixing expanded resin microballoons with a low-molecular-weight silicone rubber to prepare a compound A, mixing a high-molecular-weight silicone rubber with the compound A to prepare a silicone rubber compound, and heating the silicone rubber compound at a temperature lower than a softening point of the resin microballoons to cure the silicone rubbers.

In a final stage of printing or copying in image-forming apparatuses such as an electrophotographic copy machine, a facsimile, and a laser beam printer, a heat fixing method is generally employed in which an image is fixed by bringing a pressure roller into contact with a fixing sleeve, fixing tube, or fixing roller having a heating source therein under pressure, and causing a transfer-receiving material having a transferred toner image thereon to pass therebetween, thus melting a toner by heating.
A rubber-covered roller including a core serving as a roller base and a rubber layer for imparting elasticity, the rubber layer being disposed on the core, is widely used as a pressure roller. A known example of the rubber layer for imparting elasticity is composed of a rubber sponge, in particular, a silicone rubber sponge, containing pores (air bubbles) dispersed therein.
A silicone rubber sponge containing air bubbles dispersed therein can be produced by, for example, a method including dispersing a foaming agent in a silicone rubber, and then curing the silicone rubber while foaming the foaming agent. However, according to this method, the resulting rubber surface may become uneven because, for example, foamed cells are exposed through a wall of the silicone rubber or an irregular foaming stress is generated in the silicone rubber and the stress is released. When depressions are formed on the rubber surface, the depressions remain on the surface even in the case where a releasing layer is formed on the rubber surface, which may result in a problem of stains forming on the pressure roller due to a molten toner, etc.
To address the above problem, a method for producing a silicone rubber sponge containing air bubbles dispersed therein has also been studied in which unexpanded resin microballoons are mixed in a liquid silicone rubber and the rubber is then cured by heating while expanding the resin microballoons. However, this method tends to cause a problem of unevenness of air bubbles. Consequently, a method has also been proposed in which (expanded) resin microballoons that have been expanded in advance are mixed in a liquid silicone rubber and the silicone rubber is then cured at a temperature equal to or lower than the melting point of the resin. For example, PTL 1 discloses a silicone rubber sponge containing air bubbles (pores) formed by expanded resin microballoons dispersed therein, and a pressure roller including an elastic layer composed of this silicone rubber sponge.
This elastic layer is formed by applying, onto a core, a mixture prepared by dispersing expanded resin microballoons in a liquid silicone rubber, and curing the liquid silicone rubber by conducting heating at a temperature lower than a softening point of the resin microballoons, and the resin microballoons are broken after curing. This is because when shells of the resin microballoons remain in the resulting silicone rubber sponge, the shells may be broken as a result of thermal history during use of the silicone rubber sponge as a pressure roller and thus the fixing performance may vary. Thus, this problem is solved by breaking the shells in advance. This silicone rubber sponge is widely used as a pressure roller in an apparatus for forming a monochrome image.

Silicone rubber sponge and rubber-covered roller


A system and method for excavating a subterranean formation according to which a fluid is introduced into a vessel to draw a plurality of impactors into the vessel to form a suspension. The suspension is discharged from the vessel and into another vessel, and fluid is introduced into the other vessel to draw the suspension into the other vessel. A suspension is formed in the other vessel that is discharged towards the formation to remove a portion of the formation.

This disclosure relates to a system and method for excavating a formation, such as to form a well bore for the purpose of oil and gas recovery, to construct a tunnel, or to form other excavations in which the formation is cut, milled, pulverized, scraped, sheared, indented, and/or fractured, (hereinafter referred to collectively as "cutting"). The cutting process is a very interdependent process that preferably integrates and considers many variables to ensure that a usable bore is constructed. As is commonly known in the art, many variables have an interactive and cumulative effect of increasing cutting costs. These variables may include formation hardness, abrasiveness, pore pressures, and formation elastic properties. In drilling wellbores, formation hardness and a corresponding degree of drilling difficulty may increase exponentially as a function of increasing depth. A high percentage of the costs to drill a well are derived from interdependent operations that are time sensitive, i.e., the longer it takes to penetrate the formation being drilled, the more it costs. One of the most important factors affecting the cost of drilling a wellbore is the rate at which the formation can be penetrated by the drill bit, which typically decreases with harder and tougher formation materials and formation depth.
There are generally two categories of modern drill bits that have evolved from over a hundred years of development and untold amounts of dollars spent on the research, testing and iterative development. These are the commonly known as the fixed cutter drill bit and the roller cone drill bit. Within these two primary categories, there are a wide variety of variations, with each variation designed to drill a formation having a general range of formation properties. These two categories of drill bits generally constitute the bulk of the drill bits employed to drill oil and gas wells around the world.
Each type of drill bit is commonly used where its drilling economics are superior to the other. Roller cone drill bits can drill the entire hardness spectrum of rock formations. Thus, roller cone drill bits are generally run when encountering harder rocks where long bit life and reasonable penetration rates are important factors on the drilling economics. Fixed cutter drill bits, on the other hand, are used to drill a wide variety of formations ranging from unconsolidated and weak rocks to medium hard rocks.
In the case of creating a borehole with a roller cone type drill bit, several actions effecting rate of penetration (ROP) and bit efficiency may be occurring. The roller cone bit teeth may be cutting, milling, pulverizing, scraping, shearing, sliding over, indenting, and fracturing the formation the bit is encountering. The desired result is that formation cuttings or chips are generated and circulated to the surface by the drilling fluid. Other factors may also affect ROP, including formation structural or rock properties, pore pressure, temperature, and drilling fluid density. When a typical roller cone rock bit tooth presses upon a very hard, dense, deep formation, the tooth point may only penetrate into the rock a very small distance, while also at least partially, plastically "working" the rock surface.
One attempt to increase the effective rate of penetration (ROP) involved high-pressure circulation of a drilling fluid as a foundation for potentially increasing ROP. It is common knowledge that hydraulic power available at the rig site vastly outweighs the power available to be employed mechanically at the drill bit. For example, modem drilling rigs capable of drilling a deep well typically have in excess of 3000 hydraulic horsepower available and can have in excess of 6000 hydraulic horsepower available while less than one-tenth of that hydraulic horsepower may be available at the drill bit. Mechanically, there may be less than 100 horsepower available at the bit/rock interface with which to mechanically drill the formation.
An additional attempt to increase ROP involved incorporating entrained abrasives in conjunction with high pressure drilling fluid ("mud"). This resulted in an abrasive laden, high velocity jet assisted drilling process. Work done by Gulf Research and Development disclosed the use of abrasive laden jet streams to cut concentric grooves in the bottom of the hole leaving concentric ridges that are then broken by the mechanical contact of the drill bit. Use of entrained abrasives in conjunction with high drilling fluid pressures caused accelerated erosion of surface equipment and an inability to control drilling mud density, among other issues. Generally, the use of entrained abrasives was considered practically and economically unfeasible. This work was summarized in the last published article titled "Development of High Pressure Abrasive-Jet Drilling," authored by John C. Fair, Gulf Research and Development. It was published in the Journal of Petroleum Technology in the May 1981 issue, pages 1379 to 1388.
Another effort to utilize the hydraulic horsepower available at the bit incorporated the use of ultra-high pressure jet assisted drilling. A group known as FlowDril Corporation was formed to develop an ultra-high-pressure liquid jet drilling system in an attempt to increase the rate of penetration. The work was based upon U.S. Pat. No. 4,624,327 and is documented in the published article titled "Laboratory and Field Testing of an Ultra-High Pressure, Jet-Assisted Drilling System" authored by J. J. Kolle, Quest Integrated Inc., and R. Otta and D. L. Stang, FlowDril Corporation; published by SPE/IADC Drilling Conference publications paper number 22000. The cited publication disclosed that the complications of pumping and delivering ultrahigh-pressure fluid from surface pumping equipment to the drill bit proved both operationally and economically unfeasible.
Another effort at increasing rates of penetration by taking advantage of hydraulic horsepower available at the bit is disclosed in U.S. Pat. No. 5,862,871. This development employed the use of a specialized nozzle to excite normally pressured drilling mud at the drill bit. The purpose of this nozzle system was to develop local pressure fluctuations and a high speed, dual jet form of hydraulic jet streams to more effectively scavenge and clean both the drill bit and the formation being drilled. It is believed that these hydraulic jets were able to penetrate the fracture plane generated by the mechanical action of the drill bit in a much more effective manner than conventional jets were able to do. ROP increases from 50% to 400% were field demonstrated and documented in the field reports titled "DualJet Nozzle Field Test Report-Security DBS/Swift Energy Company," and "DualJet Nozzle Equipped M-1LRG Drill Bit Run". The ability of the dual jet ("DualJet") nozzle system to enhance the effectiveness of the drill bit action to increase the ROP required that the drill bits first initiate formation indentations, fractures, or both. These features could then be exploited by the hydraulic action of the DualJet nozzle system.
Due at least partially to the effects of overburden pressure, formations at deeper depths may be inherently tougher to drill due to changes in formation pressures and rock properties, including hardness and abrasiveness. Associated in-situ forces, rock properties, and increased drilling fluid density effects may set up a threshold point at which the drill bit drilling mechanics decrease the drilling efficiency.
Another factor adversely effecting ROP in formation drilling, especially in plastic type rock drilling, such as shale or permeable formations, is a build-up of hydraulically isolated crushed rock material, that can become either mass of reconstituted drill cuttings or a "dynamic filtercake", on the surface being drilled, depending on the formation permeability. In the case of low permeability formations, this occurrence is predominantly a result of repeated impacting and re-compacting of previously drilled particulate material on the bottom of the hole by the bit teeth, thereby forming a false bottom. The substantially continuous process of drilling, re-compacting, removing, re-depositing and re-compacting, and drilling new material may significantly adversely effect drill bit efficiency and ROP. The re-compacted material is at least partially removed by mechanical displacement due to the cone skew of the roller cone type drill bits and partially removed by hydraulics, again emphasizing the importance of good hydraulic action and hydraulic horsepower at the bit. For hard rock bits, build-up removal by cone skew is typically reduced to near zero, which may make build-up removal substantially a function of hydraulics. In permeable formations the continuous deposition and removal of the fine cuttings forms a dynamic filtercake that can reduce the spurt loss and therefore the pore pressure in the working area of the bit. Because the pore pressure is reduced and mechanical load is increased from the pressure drop across the dynamic filtercake, drilling efficiency can be reduced.
There are many variables to consider to ensure a usable well bore is constructed when using cutting systems and processes for the drilling of well bores or the cutting of formations for the construction of tunnels and other subterranean earthen excavations. Many variables, such as formation hardness, abrasiveness, pore pressures, and formation elastic properties affect the effectiveness of a particular drill bit in drilling a well bore. Additionally, in drilling well bores, formation hardness and a corresponding degree of drilling difficulty may increase exponentially as a function of increasing depth. The rate at which a drill bit may penetrate the formation typically decreases with harder and tougher formation materials and formation depth.
When the formation is relatively soft, as with shale, material removed by the drill bit will have a tendency to reconstitute onto the teeth of the drill bit. Build-up of the reconstituted formation on the drill bit is typically referred to as "bit balling" and reduces the depth that the teeth of the drill bit will penetrate the bottom surface of the well bore, thereby reducing the efficiency of the drill bit. Particles of a shale formation also tend to reconstitute back onto the bottom surface of the bore hole. The reconstitution of a formation back onto the bottom surface of the bore hole is typically referred to as "bottom balling". Bottom balling prevents the teeth of a drill bit from engaging virgin formation and spreads the impact of a tooth over a wider area, thereby also reducing the efficiency of a drill bit. Additionally, higher density drilling muds that are required to maintain well bore stability or well bore pressure control exacerbate bit balling and the bottom balling problems.
When the drill bit engages a formation of a harder rock, the teeth of the drill bit press against the formation and densify a small area under the teeth to cause a crack in the formation. When the porosity of the formation is collapsed, or densified, in a hard rock formation below a tooth, conventional drill bit nozzles ejecting drilling fluid are used to remove the crushed material from below the drill bit. As a result, a cushion, or densification pad, of densified material is left on the bottom surface by the prior art drill bits. If the densification pad is left on the bottom surface, force by a tooth of the drill bit will be distributed over a larger area and reduce the effectiveness of a drill bit.
There are generally two main categories of modern drill bits that have evolved over time. These are the commonly known fixed cutter drill bit and the roller cone drill bit. Additional categories of drilling include percussion drilling and mud hammers. However, these methods are not as widely used as the fixed cutter and roller cone drill bits. Within these two primary categories (fixed cutter and roller cone), there are a wide variety of variations, with each variation designed to drill a formation having a general range of formation properties.
The fixed cutter drill bit and the roller cone type drill bit generally constitute the bulk of the drill bits employed to drill oil and gas wells around the world. When a typical roller cone rock bit tooth presses upon a very hard, dense, deep formation, the tooth point may only penetrate into the rock a very small distance, while also at least partially, plastically "working" the rock surface. Under conventional drilling techniques, such working the rock surface may result in the densification as noted above in hard rock formations.
With roller cone type drilling bits, a relationship exists between the number of teeth that impact upon the formation and the drilling RPM of the drill bit. A description of this relationship and an approach to improved drilling technology is set forth and described in U.S. Pat. No. 6,386,300 issued May 14, 2002. The '300 patent discloses the use of solid material impactors introduced into drilling fluid and pumped though a drill string and drill bit to contact the rock formation ahead of the drill bit. The kinetic energy of the impactors leaving the drill bit is given by the following equation: Ek=½ Mass(Velocity)2. The mass and/or velocity of the impactors may be chosen to satisfy the mass-velocity relationship in order to structurally alter the rock formation.

Impact excavation system and method with two-stage inductor


The invention relates to the preparation of compounds (I)

The invention concerns the technical field of processes for preparing herbicides or plant growth regulators.
It is known that heterocyclically substituted phenylsulfonylureas which carry an amino group or a functionalized amino group on the phenyl ring possess herbicidal and plant growth-regulatory properties (EP-A-1515; EP-A-7687 (=U.S. Pat. No. 4,383,113); EP-A-30138 (=U.S. Pat. No. 4,394,506); U.S. Pat. Nos. 4,892,946; 4,981,509; EP-A-116518 (=U.S. Pat. Nos. 4,664,695, 4,632,695)), WO-94/10154. In addition, German Patent Application P 4415049.0 (WO 95/29899) has proposed acylaminosulfonylureas as herbicides. The cited literature includes descriptions of processes for preparing sulfonylureas. The compounds having a free amino group on the phenyl ring are themselves herbicidal active ingredients or are suitable as starting compounds for preparing compounds with a substituted amino group.
Owing to the large number of reactive functional groups in the molecule, the methods for preparing aminophenylsulfonylureas can often be carried out only with low yields or poor purities. Another disadvantage is that many processes are based on the use of protecting groups, for example the tert-butyl group in the case of sulfonamides, whose elimination requires specific and difficult-to-handle reagents, such as trifluoroacetic acid. Moreover, the majority of the known processes for preparing sulfonylurea compounds are multistage and therefore give only a moderate overall yield, as a rule.
The object of the invention is therefore the provision of a process which is suitable for preparing a relatively large group of herbicides from the aminophenylsulfonylurea series and which avoids many of the abovementioned disadvantages.
The invention provides a process for preparing compounds of the formula (I) and salts thereof,
in which
(R)n is n identical or different radicals from the group consisting of halogen, alkyl and alkoxy,
n is 0, 1, 2 or 3, preferably 0 or 1, especially 0,
A is hydrogen or an acyl radical,
R1 is hydrogen or an unsubstituted or substituted hydrocarbon or hydrocarbonoxy radical having 1 to 6 carbon atoms, preferably 1 to 4 carbon atoms,
R2 is hydrogen or an unsubstituted or substituted hydrocarbon radical having a total of 1 to 10 carbon atoms, preferably 1 to 4 carbon atoms,
or the group
NR1R2 is a heterocyclic ring having 3 to 8 ring atoms which is unsubstituted or substituted and contains the nitrogen atom of the group NR1R2 as ring heteroatom and may also contain one or two further ring heteroatoms from the group consisting of N, O and S,
R3 is hydrogen or C1-C4-alkyl,
X and Y independently of one another are halogen, C1-C6-alkyl, C1-C6-alkoxy, C1-C6-alkylthio, each of the three latter radicals being unsubstituted or substituted by one or more radicals from the group consisting of halogen, C1-C4-alkoxy and C1-C4-alkylthio, or are C3-C6-cycloalkyl, C2-C6-alkenyl, C2-C6-alkynyl, C3-C6-alkenyloxy or C3-C6-alkynyloxy, and
Z is CH or N,
which comprises
1. (Stage 1) reacting the compound of the formula (II)
xe2x80x83or its salts in the presence of a halogenating agent, with formation of the carbonyl halide and its rearrangement to form the compound of the formula (III)
2. (Stage 2) then
a) subjecting the compound (III) to ammonolysis at the SO2Cl group to give the compound of the formula (IV)
xe2x80x83then reducing the compound (IV) at the nitro group to give the compound (V)
xe2x80x83and then reacting the compound (V) with the carbamate or carbamate salt of the formula (VI)
xe2x80x83in which Ar is unsubstituted or substituted phenyl and M is H, C1-C4-alkyl or a metal cation, to give the compound of the formula (I) in which R3 is, in agreement with M in formula (VI), H or C1-C4-alkyl or, if M is a metal cation, R3 is a hydrogen atom, and A=H, or
b) subjecting the compound of the formula (III) to ammonolysis at the SO2Cl group to give the abovementioned compound of the formula (IV), then reacting the compound (IV) with the carbamate or carbamate salt of the abovementioned formula (VI) to give the compound of the formula (VII)
xe2x80x83in which R3 is in agreement with M in formula (VI), either H or C1-C4-alkyl or, if M is a metal cation, is a hydrogen atom, and reducing the compound of the formula (VII) at the nitro group to give the compound of the formula (I) in which A is H, or
c) reacting the compound of the formula (III) with cyanates and with the heterocyclic amine of the formula (VIII)
xe2x80x83in which R3 is as defined in formula (I) to give the sulfonylurea of the formula (VII), which by reduction at the nitro group gives the compounds of the formula (I) in which A is H, and
3. (Stage 3) if A in the end product of the formula (I) is not hydrogen but is an acyl radical, acylating the compound of the formula (I) obtained in Stage 2, in which A is H, the radicals (R)n, R1, R2, X, Y, and Z in the formulae (II) to (VIII) being as defined for the end product of the formula (I).
In the formulae (I) to (VII) and in the formulae used below, the radicals alkyl, alkoxy, haloalkyl, haloalkoxy, alkylamino and alkylthio and their unsaturated and/or substituted counterparts may in each case be straight-chain or branched in the carbon framework. Unless indicated specifically, preference is given in the case of these radicals to the lower carbon frameworks, e.g. those having 1 to 4 carbon atoms, or, in the case of unsaturated groups, having 2 to 4 carbon atoms. Alkyl radicals, both alone and in the composite definitions such as alkoxy, haloalkyl, etc., are for example methyl, ethyl, n-propyl, isopropyl, n-butyl isobutyl, tert-butyl or 2-butyl, pentyls, hexyls, such as n-hexyl, isohexyl and 1,3-dimethylbutyl, and heptyls, such as n-heptyl, 1-methylhexyl and 1,4-dimethylpentyl; alkenyl and alkynyl radicals have the meaning of the possible unsaturated radicals corresponding to the alkyl radicals; alkenyl is for example allyl, 1-methylprop-2-en-1-yl, 2-methylprop-2-en-1-yl, but-2-en-1-yl, but-3-en-1-yl, 1-methylbut-3-en-1-yl and 1-methylbut-2-en-1-yl; alkynyl is for example propargyl, but-2-yn-1-yl; but-3-yn-1-yl, 1-methylbut-3-yn-1-yl. Halogen is for example fluorine, chlorine, bromine or iodine. Haloalkyl, haloalkenyl and haloalkynyl are alkyl, alkenyl and, respectively, alkynyl which are partially or completely substituted by halogen, preferably by fluorine, chlorine and/or bromine, in particular by fluorine or chlorine, examples being CF3, CHF2, CH2F, CF3CF2, CH2FCHCl, CCl3, CHCl2, CH2CH2Cl; haloalkoxy is for example OCF3, OCHF2, OCH2F, CF3CF2O, OCH2CF3 and OCH2CH2Cl; corresponding comments apply to haloalkenyl and other halogen-substituted radicals.
A hydrocarbon radical is a straight-chain, branched or cyclic and saturated or unsaturated aliphatic or aromatic hydrocarbon radical, for example alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl or aryl, preferably alkyl, alkenyl or alkynyl having up to 12 carbon atoms or cycloalkyl having 5 or 6 ring atoms, or phenyl; corresponding comments apply to a hydrocarbonoxy radical.
A heterocyclic radical or ring can be saturated, unsaturated or heteroaromatic; it contains one or more ring heteroatoms, preferably from the group consisting of N, O and S; it preferably has 5 or 6 members and contains 1, 2 or 3 ring heteroatoms. The radical may for example be a heteroaromatic radical or ring as defined above, or is a partially hydrogenated radical such as oxiranyl, pyrrolidinyl, piperidyl, piperazinyl, dioxolanyl, morpholinyl, and tetrahydrofuryl. Suitable substituents for a substituted heterocyclic radical are those mentioned below, and also oxo. The oxo group may also be on the ring heteroatoms, which may exist in various oxidation states in the case, for example, of N and S.
Substituted radicals, such as substituted hydrocarbon radicals, e.g. substituted alkyl, alkenyl, alkynyl, aryl, phenyl and benzyl, or substituted heteroaryl, a substituted bicyclic radical or ring or a substituted bicyclic radical, with or without aromatic components, are for example a substituted radical derived from the unsubstituted parent structure, the substituents being for example one or more, preferably 1, 2 or 3, radicals from the group consisting of halogen, alkoxy, haloalkoxy, alkylthio, hydroxyl, amino, nitro, cyano, azido, alkoxycarbonyl, alkylcarbonyl, formyl, carbamoyl, mono- and dialkylaminocarbonyl, substituted amino such as acylamino, mono- and dialkylamino, and alkylsulfinyl, haloalkylsulfinyl, alkylsulfonyl, haloalkylsulfonyl and, in the case of cyclic radicals, also alkyl and haloalkyl and unsaturated aliphatic radicals corresponding to the saturated hydrocarbon-containing radicals mentioned, such as alkenyl, alkynyl, alkenyloxy, alkynyloxy, etc. In the case of radicals containing carbon atoms, preference is given to those having 1 to 4 carbon atoms, especially 1 or 2 carbon atoms. In general, preference is given to substituents from the group consisting of halogen, e.g. fluorine and chlorine, C1-C4-alkyl, preferably methyl or ethyl, C1-C4-haloalkyl, preferably trifluoromethyl, C1-C4-alkoxy, preferably methoxy or ethoxy, C1-C4-haloalkoxy, nitro and cyano. In this context, the substituents methyl, methoxy and chlorine are particularly preferred.
Substituted or unsubstituted phenyl is preferably phenyl which is unsubstituted or is substituted one or more times, preferably up to three times, by identical or different radicals from the group consisting of halogen, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-haloalkyl, C1-C4-haloalkoxy and nitro, examples being o-, m- and p-tolyl, dimethylphenyls, 2-, 3- and 4-chlorophenyl, 2-, 3- and 4-trifluoro- and -trichlorophenyl, 2,4-, 3,5-2,5- and 2,3-dichlorophenyl, and o-, m- and p-methoxyphenyl.
An acyl radical is the radical of an organic acid, for example the radical of a carboxylic acid, and radicals of acids derived therefrom, such as of thiocarboxylic acid, of unsubstituted or N-substituted iminocarboxylic acids, or is a radical of carbonic acid monoesters, of unsubstituted or N-substituted carbamic acid, sulfonic acids, sulfinic acids, phosphonic acids, phosphinic acids. Acyl is for example formyl, alkylcarbonyl such as (C1-C4-alkyl)-carbonyl, phenylcarbonyl, where the phenyl ring can be substituted, for example, as shown above for phenyl, or alkyloxycarbonyl, phenyloxycarbonyl, benzyloxycarbonyl, alkylsulfonyl, alkylsulfinyl, N-alkyl-1-iminoalkyl and other radicals of organic acids.
There is particular interest in novel processes for preparing compounds of the formula (I) or salts thereof in which
(R)n is n identical or different radicals from the group consisting of halogen, C1-C4-alkyl and C1-C4-alkoxy,
n is 0 or 1, especially 0,
A is H or acyl having 1 to 8 carbon atoms, especially 1-4 carbon atoms,
R1 is H, C1-C6-alkyl, C2-C6-alkenyl, C2-C6-alkynyl, C1-C6-alkoxy, C2-C6-alkenoxy, C2-C6-alkynoxy or C5-C6-cycloalkyl, each of the 7 latter radicals being unsubstituted or substituted by one or more radicals from the group consisting of halogen, C1-C4-alkoxy, C1-C4-haloalkoxy, C1-C4-alkylthio, mono- and di-(C1-C4-alkyl)-amino, cyano, azido, formyl, (C1-C4-alkyl)-carbonyl, (C1-C4-alkoxy)-carbonyl, C1-C4-alkylsulfinyl and C1-C4-alkylsulfonyl, or is phenyl which is unsubstituted or substituted by radicals from the group consisting of halogen, C1-C4-alkyl, C1-C4-alkoxy, C1-C4-haloalkyl, C1-C4-haloalkoxy and nitro,
R2 is H, C1-C6-alkyl, C2-C6-alkenyl or C2-C6-alkynyl, each of the three latter radicals being unsubstituted or substituted by one or more radicals from the group consisting of halogen, C1-C4-alkoxy, C1-C4-haloalkoxy, C1-C4-alkylthio, mono- and di-(C1-C4-alkyl)-amino, cyano, azido, formyl, (C1-C4-alkyl)-carbonyl, (C1-C4-alkoxy)-carbonyl, C1-C4-alkylsulfinyl and C1-C4-alkylsulfonyl,
or the group
NR1R2 is a heterocyclic ring of 4, 5 or 6 ring atoms which may contain up to two further ring heteroatoms from the group consisting of N and O in the ring and which is unsubstituted or substituted by one or more radicals from the group consisting of C1-C4-alkyl,
R3 is H or CH3,
one of the radicals X and Y is halogen, C1-C2-alkyl, C1-C2-alkoxy, C1-C2-alkylthio, each of the three latter radicals being unsubstituted or substituted by one or more radicals from the group consisting of halogen, C1-C2-alkoxy and C1-C2-alkylthio, or is mono- or di-(C1-C2-alkyl)amino, preferably halogen, methyl or methoxy, and
the other of the radicals X and Y is C1-C2-alkyl, C1-C2-haloalkyl, C1-C2-alkoxy, C1-C2-haloalkoxy or C1-C2-alkylthio, preferably methyl or methoxy, and
Z is CH or N, preferably CH.
Preference is also given to novel processes for preparing compounds of the formula (I) or salts thereof in which
A is hydrogen, formyl, (C1-C4-alkyl)carbonyl, which is unsubstituted or substituted by one or more radicals from the group consisting of halogen and (C1-C4)-alkoxy, or is (C1-C4-alkoxy)-carbonyl, phenoxycarbonyl, phenylcarbonyl, phenyl-(C1-C4-alkyl)-carbonyl or phenyl-(C1-C4-alkoxy)-carbonyl, where the phenyl in each of the 4 latter radicals is unsubstituted or substituted, A preferably being formyl, acetyl, propionyl, methoxycarbonyl, ethoxycarbonyl, benzoyl or benzyloxycarbonyl, especially formyl, (C1-C4-alkyl)-carbonyl or (C1-C4-alkoxy)-carbonyl.
Preference is given to novel processes for preparing compounds of the formula (I) or salts thereof in which
R1 is H, C1-C2-alkyl, C1-C2-alkoxy, phenyl which is unsubstituted or substituted by one or more radicals from the group consisting of halogen, C1-C2-alkyl, C1-C2-alkoxy, C1-C2-haloalkyl and C1-C2-haloalkoxy, especially methyl or ethyl,
R2 is H or C1-C2-alkyl, especially methyl or ethyl,
or the group
NR1R2 is a heterocyclic ring of 5 or 6 ring atoms which may contain up to one further ring heteroatom from the group consisting of N and O in the ring and which is unsubstituted or substituted by one or more C1-C2-alkyl radicals, especially pyrrolidinyl or piperidyl,
R3 is H or CH3, especially H.
Among the novel processes, preference is given to those in which in the compounds of the formula (I) the group of the formula NH2 on the phenyl radical is para to the group COxe2x80x94NR1R2 and meta to the SO2 group.
The invention additionally provides the novel individual stages of the overall process, and the novel intermediates thereof, especially Stage 1 and Stages 2a and 2b, to the extent that it relates to the reaction with carbamate salts (VI) in which M is a cation.
The reaction of compounds (II) to compounds (III) can be accomplished with customary halogenating agents for the preparation of carbonyl chlorides, for example with thionyl chloride or thionyl bromide. For this purpose the nitro-ortho-sulfamoyl benzoic acid (II) is reacted with an excess of halogenating agent in an aprotic organic solvent and is then heated to a temperature at which the rearrangement reaction takes place. Suitable organic solvents are aprotic organic solvents which are inert with respect to the reactants (referred to as inert solvents) and whose boiling point is above the temperature required for the rearrangement reaction. The reactants may for example be reacted homogeneously or in a heterogheterogeneous mixture, (for example in suspension) to give the desired products. For example, the reaction can be carried out in halogenated or unhalogenated aromatic hydrocarbons, such as toluene, xylene, chlorobenzene or chlorotoluene. The reaction temperatures for this halogenation are from about 50 to 100xc2x0 C. and for the rearrangement are from over 100xc2x0 C. to the boiling point of the aprotic solvent, for example from 110 to 160xc2x0 C.; in some cases rearrangement takes place to an inadequate extent even at lower temperatures, for example at 70xc2x0 C. The thionyl chloride can be used in equimolar quantities or in an excess relative to one mole of the benzoic acid. Instead of the benzoic acid derivatives it is also possible to react the corresponding salts, for example the alkali metal or alkaline earth metal salts (e.g. Na, K, Li, Mg and Ca salts), with a halogenating agent, for example thionyl chloride, to give the corresponding 2-chlorosulfonylbenzamide derivatives (III).
It is already known to react 2-(N,N-dialkyl-aminosulfonyl)-benzoic acids which are unsubstituted or carry simple alkyl groups on the phenyl ring with a fourfold to eightfold excess of thionyl chloride or thionyl bromide in benzene, dichloromethane or chloroform at room temperature (25xc2x0 C.) to give N,N-dialkyl-2-(chloro- or, respectively, -bromosulfonyl)benzamides; see K. Hovius et al., Tetrahedron Lett. 1983, 3137-3140. The corresponding reaction of the N,N-dialkyl-o-sulfamoyinitrobenzoic acids (II) was not hitherto known and did not take place under these conditions. Only by modification of the known conditions with respect to temperature and solvent does the reaction proceed with the tested nitrobenzoic acids (II) as well.
The required compounds of the formula (II) can be prepared by alternative methods. For instance, the oxidation of the methyl group of compounds of the formula (IX)
leads to the compound of the formula (II). The oxidation can be carried out, for example, by methods similar to known methods for the preparation of benzoic acids from toluenes. The toluene derivative of the formula (IX) can be obtained by reacting the sulfochloride of the formula (X) with an amine of the formula HNR1R2:
A further method of obtaining compound (II) is the ammonolysis of the sulfochloride (XI)
in which Ra is an alkyl radical such as methyl or ethyl with an amine of the formula HNR1R2 to give the sulfonamide, followed by hydrolysis of the resulting compound at the carboxylic ester group. The individual reactions can be carried out in analogy with known methods of the same type. For example, the ester functions can be hydrolyzed using alkali metal hydroxides or alkaline earth metal hydroxides, such as LiOH, NaOH, KOH, Mg(OH)2, Ca(OH)2 for example, in various polar solvents, for example methanol, ethanol, isopropanol, chlorobenzene, chlorotoluene, tetrahydrofuran, 1,2-dimethoxyethane (DME), diglyme, dimethylformamide (DMF), N,N-dimethylacetamide (DMA), N-methylpyrrolidone (NMP) or water, or solvent mixtures of suitable solvents, at temperatures, for example, between xe2x88x9220xc2x0 C. and 150xc2x0 C., preferably between xe2x88x9210xc2x0 C. and 100xc2x0 C.
The sulfonamides of the formula (IV) can be obtained in high yields by reacting the sulfochlorides (III) with ammonia (ammonolysis). The reaction can generally be carried out at temperatures from xe2x88x9220xc2x0 C. to 150xc2x0 C., preferably from xe2x88x9210xc2x0 C. to 100xc2x0 C. Suitable solvents are organic solvents inert under the reaction conditions, for example
dipolar aprotic solvents such as DMF, DMA, NMP, acetonitrile,
ethers such as tert-butyl methyl ether, dimethoxyethane (DME), THF, diethyl ether, diisopropyl ether,
esters such as ethyl acetate, butyl acetate,
chlorinated or unsubstituted hydrocarbons such as toluene, o-chlorotoluene, chlorobenzene,
alcohols such as methanol, ethanol, isopropanol,
water, or
mixtures of inert solvents.
Particularly preferred solvents are nitriles such as acetonitrile, ethers such as diethyl ether, tert-butyl methyl ether, THF or dimethoxyethane (DME), or esters such as ethyl acetate and butyl acetate, or chlorinated or unsubstituted hydrocarbons such as toluene, chlorobenzene and chlorotoluene.
The reduction of the nitro group in compounds of the formula (IV) can be carried out, for example, by catalytic hydrogenation (Stage 2, section a). A host of common commercial catalysts are suitable for the hydrogenation, examples being platinum, palladium or Raney nickel, and can be used in analogy to standard techniques. Examples of suitable organic and inorganic solvents which are inert under the reaction conditions are
dipolar aprotic solvents such as DMA, DMF, NMP or CH3CN;
esters such as ethyl acetate or butyl acetate;
ethers such as DME, diglyme, tetraglyme, THF or diethyl ether;
alcohols such as methanol or ethanol;
organic acids such as acetic acid or propionic acid;
water, or
mixtures of suitable inert solvents.
The reaction temperature can be varied, for example, between xe2x88x9220xc2x0 C. and 150xc2x0 C., preferably from xe2x88x9210xc2x0 C. to 100xc2x0 C. The hydrogen pressure can likewise be varied with n wide limits and is, for example, from 1 bar to 200 bar, preferably from 1 bar to 100 bar, in particular from 1 bar to 50 bar.
The reaction of compounds (V) with carbamates of the formula (VI) is intended to take place preferentially and with substantial selectivity at the sulfonamide group rather than at the alternative amino groups on the phenyl radical. If the compound (V) is reacted with carbamates of the formula (IV) in accordance with standard techniques, for example in acetonitrile in the presence of a sterically hindered base such as 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU), then the sulfonamide function and amino function are similar in reactivity, i.e. the chemoselectivity of the reaction is completely unsatisfactory. For example, the reaction of 5-amino-2-dimethylaminocarbonylbenzenesulfonamide with 4,6-dimethoxy-2-phenoxycarbonylaminopyrimidine in the presence of DBU leads to two products in a 2:1 ratio, namely to 5-amino-2-dimethylaminocarbonyl-N-[(4,6dimethoxypyrimidin-2-yl)aminocarbonyl]benzenesulfonamide and to 5-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonylamino]-2-dimethylaminocarbonyl-N-[(4,6-dimethoxypyrimidin-2-yl)aminocarbonyl]-benzenesulfonamide (byproduct) (see Comparison Example).
However, the reaction can surprisingly be carried out selectively in the case of the reaction with carbamate salts. In accordance with the invention, selectivities which are better, for example, than those of the reaction with carbamates of the formula (XI) in which M is hydrogen are achieved by using carbamate salts (VI), in which M is a cation, for example sodium or potassium salts of the carbamates.
For this reaction, for example, the carbamate (VI) (M=H) is first of all reacted with appropriate bases, for example alkali metal and alkaline earth metal hydroxides such as LiOH, NaOH, KOH, Mg(OH)2, Ca(OH)2 or tetraalkylammonium hydroxides such as tetramethylammonium hydroxide, or alkali metal or alkaline earth metal hydrides, for example NaH, KH, CaH2 or alkali metal or alkaline earth metal alcoholates, such as NaOCH3, NaOC2H5, sodium isopropylate, sodium tert-butylate, KOCH3, KOC2H5, potassium isopropylate, potassium tert-butylate, or mixtures of bases in appropriate solvents, to form a salt of the formula (VI) (M=cation). Suitable solvents are inert organic solvents, preferably aprotic apolar or aprotic polar solvents such as ethers (e.g. THF, DME, diethyl ether, diisopropyl ether, dioxane, tert-butylmethyl ether), amides (e.g. DMF, DMA, NMP), nonhalogenated or halogenated aromatic hydrocarbons, such as toluene, chlorotoluene or chlorobenzene. For alkali metal and alkaline earth metal salts, moreover, further suitable solvents are alcohols such as methanol, ethanol, isopropanol, or solvent mixtures. For alkali metal, alkaline earth metal and tetraalkylammonium hydroxides, moreover, water is also an appropriate solvent or solvent component. Particular preference is given to ethers, such as THF, DME or dioxane.
The resulting salts of the formula (VI) (M=cation) are advantageously produced in solution and employed without isolation for the subsequent reaction. For this purpose the salts are, for example, reacted in solution with sulfonamides of the formula (V) at temperatures from xe2x88x9240xc2x0 C. to 150xc2x0 C., preferably from xe2x88x9240xc2x0 C. to 80xc2x0 C., in particular from xe2x88x9220xc2x0 C. to 80xc2x0 C. Following acidification of the reaction solution with acids, for example with organic acids such as formic acid or acetic acid, or with mineral acids such as hydrochloric acid or sulfuric acid, the sulfonylureas of the formula (I) (A=H) (=compounds (Ixe2x80x2)) can be isolated by standard methods. A favorable yield is generally achieved at a molar ratio of sulfonamides (V) to carbamate salt (VI) of from 1:0.7 to 1:1.5. Preferred variants are the reactions of carbamates of the formula (VI) (M=H) with the hydroxides or alcoholates of alkali metals, for example KOH, NaOCH3, KOCH3, sodium tert-butylate or potassium tert-butylate, sodium isopropylate or potassium isopropylate, especially with the sterically bulky alkali metal alcoholates, in dipolar aprotic solvents such as THF, dioxane, DMF, DMA, especially THF, DME or dioxane.
An alternative route to sulfonylureas (Ixe2x80x2) (=formula (I) where A=H) is offered by the variant 2b mentioned. According to this variant, the compounds (III) are first of all reacted by ammonolysis, as in step 1 of Stage 2a), to give nitrobenzenesulfonamides of the formula (IV), which are subsequently reacted with carbamates of the formula (VI) in analogy to standard conditions in the presence of bases, for example organic nitrogen bases such as DBU or triethylamine, alkali metal or alkaline earth metal hydroxides, such as LIOH, NaOH, KOH, Mg(OH)2 or Ca(OH)2, alkali metal or alkaline earth metal alcoholates, for example NaOCH3, KOCH3, Na or K isopropylate, Na or K tert-butylate, to form the nitrosulfonylureas of the formula (VII). The ratios of the reactants are preferably from 0.7 to 1.5 equivalents of carbamates (VI) and from 0.7 to 2.2 equivalents of base, based in each case on 1 equivalent of sulfonamide (IV).
The reactions of compounds (IV) to compounds (VII) take place at temperatures of, for example, from xe2x88x9220xc2x0 C. to 100xc2x0 C., preferably from xe2x88x9210xc2x0 C. to about 70xc2x0 C., in inert organic solvents, for example in aprotic solvents such as ethers (e.g. THF, DME, dioxane, diethyl ether), acetonitrile, DMF, DMA, NMP, alcohols, esters such as ethyl acetate or butyl acetate, chlorinated aliphatic or aromatic hydrocarbons such as difluoromethane, trichloroethane, chlorobenzene or o-chlorotoluene, or protic solvents such as, for example, methanol, ethanol, isopropanol or water, or appropriate solvent mixtures.
The nitrosulfonylureas of the formula (VII) can also be obtained by analogy with the aboveescribed reaction of carbamate salts of the formula (VI) (M=cation) with sulfonamides of the formula (V) to give the sulfonylureas (Ixe2x80x2) (=formula (I) where A=H), by reaction of sulfonamides of the formula (IV) (M=cation) with carbamate salts (M=cation) (VI).
The nitrosulfonylureas (VII) can subsequently be reacted by catalytic hydrogenation to give the aminosulfonylureas (Ixe2x80x2) of the formula (I) in which A is H, The hydrogenation can be carried out in analogy to the above-described hydrogenation of compounds of the formula (IV), in accordance with standard techniques. When an aqueous medium is used as solvent, basic solutions or buffered aqueous solutions having a pH of from 5 to 13, preferably from 7 to 11, are particularly suitable. Alternatively, instead of the neutral nitrosulfonylureas (VII) their salts can be employed for the hydrogenation. Examples of suitable cations to partner the sulfonylurea anions of the formula (VII) are alkali metal or alkaline earth metal cations, for example Li+, Na+, K+, Cs+, Mg2+, Ca2+, or ammonium cations, for example NH4+, HN(CH3)3+, N(CH3)4+, N(C2H5)4+, HN(C2H5)3+, (DBU-H)30  or mixtures of these cations.
The method of the reaction of the sulfochloride (III) with cyanates, for example sodium cyanate or potassium cyanate, and heterocyclic amines (VII) to give compounds (VII) (variant 2c) is described in principle in the abovementioned literature; see, for example, German Patent Application P 4415049.0 (WO 95/29899). The subsequent reduction of the nitro group can be carried out, as in the case of the compound (IV), in accordance with customary methods, for example preferably by catalytic reduction as already described above for compounds (VII).
In the 3rd stage, the compounds (Ixe2x80x2) obtained from the second stage, of the formula (I) in which A is H, can be acylated to give herbicidal active ingredients (Ixe2x80x3) of the formula (I) in which A is an acyl radical. Surprisingly, acylation takes place very selectively at the amino group attached to the phenyl ring using customary acylating agents. Acylation is accomplished, for example, in an aprotic organic solvent and can be carried out using customary acylating reagents. Examples of acylating agents are anhydrides, carbonyl halides, activated esters (=active esters), such as carbonic esters and chlorocarbonic esters, sulfonyl chlorides, etc. For example, a range of very good standard techniques is available for the formylation of the amino function of sulfonylureas (Ixe2x80x2) of the formula (I) in which A is H. Thus, the amino function can be converted into the formylamino group using mixed anhydrides of the formula (XII)
Hxe2x80x94COxe2x80x94Oxe2x80x94COxe2x80x94Rxe2x80x83xe2x80x83(XII)
R=alkyl or using formic acid.
Mixed anhydrides can be prepared by methods known from the literature, from formic acid and from carboxylic anhydrides, for example acetic anhydride, or from salts of formic acid, for example sodium formate, and carbonyl chlorides, for example acetyl chloride or pivaloyl chloride.
The individual intermediates of the novel process are novel and the invention likewise relates to them.
The individual reaction stages of the overall process described can be carried out in homogenous solution or else in supersaturated, i.e. kinetically stable, solution or in heterogeneous suspension in order, in each case, to obtain advantageous space-time yields. In such procedures, very good yields and purities are generally obtained. By a skillful combination of the individual stages it is possible to obtain overall yields of sulfonylureas of the formula (I), preferably those having the acylamino function para to the carboxamido group, which are superior to the yields described in the literature (DE 4415049, WO 95/29899).
By a skillful choice of reaction conditions it is possible, moreover, to combine two or more stages to form one-pot reactions or cascade reactions. By this means it is possible in some cases to make considerable improvements in both the yield and the space-time yield.
Preference is given to the preparation of compounds of the formula (I) in which n is 0, R3 is H and the amino group on the phenyl radical is para to the carboxamido group and meta to the SO2 function (=compounds (Ia)). Particular preference is attached to the novel process and its component stages wherein a compound of the formula (IIa)
in which R1 and R2 are as defined for formula (I) is reacted in the presence of a halogenating agent, with the formation of acid halide and with rearrangement, to form the compound of the formula (IIIa),
which is then converted with ammonia to the amide of the formula (IVa)
which is then reduced at the nitro group to form the compound (Va),
which in turn is reacted with carbamate salt of the formula (VIa)
to give the compound (Ia).
In the Preparation Examples below, quantities and percentages are by weight unless stated otherwise. xe2x80x9cm.p.xe2x80x9d denotes melting point.

Processes for preparing aminophenylsulfonylureas, and intermediates therefor

Abstract: in which A=H or acyl and R1, R21, R3, R, n, X, Y and Z are as defined in claim 1 by halogenation and rearrangement of compounds (II) (optionally salt) to give compounds (III)

Abstract: a) ammonolysis of (III) to (IV), reduction of the nitro group and reaction with carbamate (salts) (VI) of the formula Arxe2x80x94OCOxe2x80x94N(M)xe2x80x94Het, where Ar=phenyl, M=H or cation and Het=heterocycle from formula (I), to give compounds (I) (A=H), or

Abstract: b) ammonolysis of (III) to (IV), reaction with carbamate (salt) (VI) and reduction of resulting compounds (VII) at the NO2 group to give compounds (I) (A=H), or

Abstract: c) reaction of (III) with cyanates and amines (VIII) of the formula HNR3xe2x80x94Het and reduction of the resulting compound (VII) at the NO2 group to give compounds (I) (A=H) and optional acylation if A is to be other than H. Compounds of the formulae (I) (A=H), (III), (IV), (V), (VI) (M=cation) and (VII) are novel.


In some examples, a system can include a processing resource and a memory resource. The memory resource can store machine readable instructions to cause the processing resource to: (1) collect feedback from a physical (PHY)-layer of a client at a plurality of access points, before the client is associated with any one of the plurality of access points and (2) select an access point using a client channel correlation value calculated from the PHY-layer feedback, wherein the selected access point serves the client and a client group concurrently using precoding.

In computer networking, a wireless access point (AP) is a device that allows wireless devices to connect to a wired network using wireless fidelity (Wi-Fi), or related standards. Precoding, or more specifically beamforming, technology allows an access point to support multiple, concurrent data streams to a group of clients. Precoding allows multiple data streams to be emitted from a transmit antenna with independent and appropriate weightings such that the link throughput is maximized at the receiver output.

Hewlett Packard Enterprise Development LP


A low cost image transmission optical system for an inflexible type endoscope comprising two rod-like lenses disposed in a front-to-back symmetrical manner, each rod-like lens consisting of two correcting lenses encapsulating therebetween a fluid; said fluid, for example, may be water or an optical liquid. The said encapsulated fluid image transmission optical system being arranged that the image brightness and its chromaticity, curvature of field and astigmatic residuals are favorably corrected, and that the said arrangement is not susceptible to breakage when a bending load is applied to the shaft of the endoscope.

A) Field of the Invention
The present invention relates to a biconvex rod-lens for the optics assemblies of medical or technical endoscopes, and a rod-lens comprising a fluid encapsulated between two correcting lenses, the external surfaces of which are convex in shape and, more particularly, to an inexpensive and durable image transmission optical system to be used with an inflexible-type endoscope or the like, which is arranged to transmit an image by using a plural number of relay lenses.
B) Description of the Prior Art
An inflexible-type endoscope 1 illustrated in FIG. 1 consists of an eyepiece 2 to the distal end of which is affixed a connector 7a for attachment of a fiber optics light delivery assembly (not shown) and a tubular outer shaft 3 receiving the optical elements of the assembly. The said optical elements, shown in FIG. 1A, consist of the objective 8 which is arranged near the distal end of shaft 3, and a series of lenses 9 arranged to transmit an image from the proximal end of objective 8 to the distal portion of eyepiece 2.
According to the prior art, as illustrated in FIG. 2, an image transmission optical system consists of two rod-like cemented doublets 9, each consisting of the biconvex positive lens element 12 made, for example, from a crown glass and the concavo-convex negative lens element 14 cemented to lens 12, and being made, for example, from a flint glass. Said image transmitting optical system is arranged so that the convex surfaces of the negative lens elements 14 thereof face each other in opposition, said assemblies embraced in a thin-walled inner tube 10 within the outer shaft 3 in an eccentric and interlocking relationship. The said rod-like cemented doublets 9 are held in longitudinally spaced relationship by means of thin-walled tubular spacers 11. The shaft 3 and inner tube 10 cooperate to define a space which has a crescent-shaped cross section and in which are arranged fiber optics light guides 7 for transmitting light fed through connector 7a, to the distal end of endoscope assembly 1.
The rod-like lens 9, an enlarged view of which is shown as FIG. 3, is hereinbefore described as a cemented doublet purely on the basis that such nomenclature is a suitable matrix for optical design purposes. The positive lens 12 of a cemented doublet 9, however, is not amenable to low cost, volume manufacturing. Accordingly, it has become customary and prudent to divide positive lens 12 of rod-like lens 9 into three parts, to wit, plano-convex lens 12a, plano-plano lens 12b, and plano-convex lens 12c, so that said lenses can be economically and simultaneously processed as individual parts in multiples.
Once fabricated, the individual lenses are subsequently joined as a cemented assemblage comprising lens 12a, lens 12b, and lens 12c which is equivalent in form and function to monolithic rod lens 12. Said lens assembly, as shown in FIG. 4, is cemented to negative lens 14 to form a quadruplet lens assembly 13 which is equivalent in form and function to doublet 9. It should also be mentioned in passing that the fractionation process of rod-like lens 12 has its limits. Typically, there is economic justification for dividing the rod-like lens 12 into three or fewer pieces; however, should the rod-like lens 12 be required to be processed in four or more pieces, the cost of assembly outweighs the potential savings afforded by fabricating the lenses in multiples.
In its clinical application, the endoscope 1 is inserted into a human subject by grasping it by its proximal end, manipulating its distal end of shaft 3 through a natural or incised aperture, into the interior of a viscera. Such procedure may inadvertently cause the outer tube 3 to be deformed or bent at its approximate mid-length, the extent of which depending on the anatomy of the viscera, the force applied and the modulus of elasticity of the outer tube 3. As a concomitant result of the bending of outer tube 3, inner tube 10 is subjected to not only bending forces but also to compressive forces. Due to the small diameter and considerable length of the rod-like lens 9 and given that it is in a close tolerance embrace with inner tube 10, said lenses are prone to fracture when inner tube 10 is otherwise compressed and bent, especially at the cemented joints.
There is known an image transmitting optical system having a composition as illustrated in FIG. 5. Said known image transmitting optical system is composed of rod-like lens assembly 13, in which the mechanical diameter at the middle of the rod lens is less than the outer diameter at its ends, thus providing clearance between the mid-portion of the rod-like lens and inner tube 10. Rod lenses so shaped are supported in the inner tube 10 merely at their end regions, so that the lens assembly 13 is purported to be protected from fracture or breakage at the cemented joints when the inner tube 10 is bent.
There is known another image transmitting optical system having a composition as illustrated in FIG. 6. Said image transmitting optical system is composed of rod-like lens assembly 13, in which there is present at least one cylindrical collar of greater diameter than the adjacent lengths of each of the rods. Rod lenses so shaped are supported in their inner tube 10 only by way of the said collars, thus providing clearance between the rod-like lens and the inner tube 10 at the regions adjacent to the cylindrical collars and therefore purporting to protect the cemented joint from stress and possible fracture when the inner tube 10 is bent.
The aforementioned known methods of eliminating the possibilities for stress fractures of the rod lenses in image transmitting optical systems have, nevertheless, several significant drawbacks.
First and foremost, there remains, despite the aforementioned precautions, the distinct possibility that the cemented joints located at either ends of the rod-like lenses may be subjected to shear stress sufficient for risk of fracture. This is simply the result of the aforementioned mounting constraints existing at one end portion or both end portions of the rod-like lens assembly where one or more cemented joints may be located. Second, the economy of manufacture is impacted by the additional requirements of edging and centering the rod-like lens assembly which does not exhibit a uniform diameter along its length. Third, by constraining the diameter of the rod-like lenses of the image transmitting optical system for the purpose of eliminating stress fractures when the inner tube 10 is bent, an unnecessarily restrictive aperture stop and/or field stop my be created which places an upper limit upon the maximum value to which the image diameter, numerical aperture, or both, may reach. Consequently, this may have an unfavorable effect upon the luminous energy throughput or etendue of the image transmitting optical system.
Thus, a need has arisen for an image transmitting optical system which is inexpensive, durable and energetically efficient relative to known image transmitting optical systems. This need is pronounced when it is desired to utilize the said image transmitting optical system in an inflexible-type endoscope.

Fluid image transmitting optical system for endoscopes


A method and system for managing and applying entitlements is described herein. An identity integration server centrally manages data associated with entitlements for a plurality of identities. The integration server may select one of a plurality of workflows. One or more of a plurality of entitlements to be used in the workflow are selected, and a set of identities for which the workflow is applicable is selected. A determination is made as to whether the workflow should be run on the identities. If so, then the workflow is initiated. The one or more entitlements are then added to a granted entitlements list. Then, a separate process may be initiated to apply the one or more entitlements to the one or more identities.

Entitlements describe a capability that can be enabled or disabled for a given identity on a given application or system. Entitlements are usually granted to identities based on a business process. For example, each full-time employee may be given an email account if a manager approves. In this example, if the employee has full-time status, an e-mail notification would be sent to the manager for approval. Once the manager approval is received, an email account may be created for the employee.
In a typical provisioning application, entitlements are applied inline with the business process. If entitlements are applied directly to an application, it would require the executor of the business process to have permissions to the application in which the entitlement is being applied to. In addition, it may be costly to enable the entitlements on the application depending on factors such as network traffic and system load. Different business processes may also be applying the same entitlement. In this case, the system may end up with redundant calls to the application. Furthermore, the system may apply the entitlement onto the application in an inconsistent manner.

Management and application of entitlements


A fluid diverter system for a drilling facility comprises a diverter housing (15; 15′) fluidly connected to a tubular (3, 42, 43) extending to a subsea well. The diverter housing (15; 15′) comprising a movable diverter element (2) for closing off the diverter housing, a first fluid conduit (44) connected to a mud system and comprising a first valve (5), at least one second fluid conduit (20; 20′) leading from an outlet (46; 46′) in the diverter housing to an overboard location and comprising a second valve (1; 48), and a third fluid conduit (16) connected to a mud/gas separator (MGS) (13) and comprising a third valve (4). The MGS (13) is arranged below the outlet (50) of the diverter line, whereby riser fluids may be fed from the diverter housing (15) to the MGS (13) by means of gravity flow. The diverter valve (1; 48) on a leeward side of the drilling facility is configured to be open before the diverter element (2) closes around the tubular (3).

Diverter systems for use in subsea drilling into hydrocarbon wells are well known. Originally, diverter systems were installed on drill ships or semi-submersible drilling rigs in order to handle shallow gas when drilling with a marine riser on top hole sections before the Blow-Out Preventer (BOP) was installed. Today it is more common to drill the top hole sections with seawater or water based mud and with return to seabed or "riserless" return to the rig.
Today, the main purpose of the diverter system is to handle gas that for some reason has entered the riser after the BOP is shut in on a so-called "kick". A kick is a situation where hydrocarbons, water, or other formation fluid enters the wellbore during drilling, because the pressure exerted by the column of drilling fluid is not great enough to overcome the pressure exerted by the fluids in the formation being drilled. As the industry is going to deeper water it has been more difficult for the drillers to detect a kick early because the gas will be in liquid or dense phase, due the static pressure at sea level (where the BOP is located). Hydrocarbons in liquid or dense phase are much less compressible than hydrocarbons in gas phase. A typical natural gas will go into dense phase if the pressure is above 153.5 bara (Cricondenbar) and temperature between −29° C. (Critical temperature) and +99° C. (Cricondentherm). As the gas (in liquid or dense phase) travels up the marine riser, the static pressure is reduced, and the gas goes from liquid/dense phase to gas/vapour phase and expands several hundred times.
When the gas is expanding in the riser it may fill the entire annulus, pushing the static column of mud back to the rig, even if the BOP is closed. As the static mud column is reduced and the gas travels up the riser, the mud will come back at an accelerating and increasing flow rate. When the diverter system is activated, this mud and gas will be diverted safely overboard.
On many rigs, a so-called "mud/gas separator" (MGS) has been utilized in the diverter system in an attempt to separate the mud from the gas and return the mud to the system, thus avoiding mud discharge to the sea. Publication "API RP 64, RECOMMENDED PRACTICE FOR DIVERTER SYSTEMS EQUIPMENT AND OPERATIONS", issued by the American Institute of Technology (API) states in section 7.2.4, entitled "Inadvertent Gas Entry into the Riser", that:                "Shallow gas flows are not the only application for a diverter system when using a marine riser. Gas may inadvertently enter the riser while drilling at any depth when the BOP is shut-in on a kick. Gas may also enter the riser if the rams leak after the BOP is closed. Gas in the riser may be safely removed by diverting the flow overboard. In some designs, a mud/gas separator is utilized in the diverter system to separate the gas from the mud and return the mud to the system. Again, the design should not allow the diverter to completely shut-in the well."
The way this is solved in the prior art is that the diverter element, the return flow line and the diverter lines have been closed at the same time, forcing the fluid returning from the riser to go up to the MGS located at a higher level. This is illustrated in FIG. 1, which is a disclosure on page 114 in the BP public report entitled "Deepwater Horizon Accident Investigation Report" (published Sep. 8, 2010).
The dangerous parts of this design is that the flow rate of mud returning from the riser is much higher than the design capacity of the MGS, resulting in filling of MGS and vent line. On most of the rigs with this system it is up to the driller (operating procedures) to open the diverter overboard valve if he believes that the returns flow exceeds the capacity of the MGS.
In some rigs, an extra high level trip in the MGS and/or high pressure trip in the diverter housing has been installed to automatically open the diverter overboard line on high level in MGS or high pressure in the diverter housing.
In either one of these designs, the dangerous part is that the available time in which to take the appropriate action, i.e. before the vent line of the MGS is completely filled, is very limited. At the time when high level in the MGS or high pressure in the diverter have been reached, the mud returning from the riser is in a highly accelerating mode and the time available for opening the diverter valve is very limited.
A slug of heavy mud accelerating up the MGS vent line followed by a two phase flow and finally a large gas release will create an increased pressure in the diverter housing and possible leakage in the slip joint resulting in gas being release under the rig at the slip joint connection. A worst case scenario of such an event is the Deepwater Horizon disaster.
The present inventor has devised and embodied the invention to overcome the shortcomings of the prior art and to obtain further advantages.

Fluid diverter system for a drilling facility


Described herein is a method for manufacturing a stack of semiconductor materials in which a growth substrate is separated from the stack after a semiconductor material, e.g., a Group III nitride semiconductor material, is grown on the substrate. The separation is effected in a spalling procedure in which spalling-facilitating layers are deposited over a protective cap layer that is formed over the Group III-nitride semiconductor material. Such spalling-facilitating layers may include a handle layer, a stressor layer, and an optional adhesion layer. The protective cap layer protects the Group III-nitride from being damaged by the depositing of one or more of the spalling-facilitating layers. After spalling to remove the growth substrate, additional processing steps are taken to provide a semiconductor device that includes undamaged semiconductor material. In one arrangement, the semiconductor material is GaN and includes p-doped GaN region that was undamaged during manufacturing.

Technical Field
The present invention relates to Group III nitride semiconductor devices that are prepared with spalling, and more particularly to GaN semiconductor devices provided with a protective cap layer that protects the Group III nitride semiconductor material during spalling and when preparing for spalling.
Description of the Related Art
Spalling may be employed to separate semiconductor materials from a substrate on which the semiconductor materials have been grown. With the mechanical forces involved in separating the materials by spalling, there are times when including a stressor layer among the stack of layers aids in separation by spalling. For example, some semiconductor materials exhibit relatively high fracture toughness and so it could be useful to include a stressor layer. Gallium nitride (GaN) is an example of a high-fracture toughness semiconductor material. Further, to assure good adhesion between the layers, an adhesion layer may also be included in the stack of layers prior to separation by spalling.
Sputtering may be employed in depositing an adhesion layer, such as a metal or metal-based adhesion layer. Sputtering may provide a metal or metal-based adhesion layer with stronger bonding properties when compared to other deposition methods, such as thermal evaporation. However, certain materials are not suited for receiving a sputter-deposited layer because the sputtering method can damage the deposit-receiving material. One such material is gallium nitride (GaN), and in particular, a GaN material that has been doped with a p-type dopant ("pGaN" or "p-doped GaN"). Exposure to the plasma during the initial stages of deposition may damage the surface of p-doped GaN, possibly to an extent that renders the p-doped GaN ineffective as a semiconductor material. For example, surface damage may render p-doped GaN non-conducting.

Protective capping layer for spalled gallium nitride

INTERNATIONAL BUSINESS MACHINES CORPORATION