imony catalysts, to yield more highly fluorinated products.
A more recent development in this field is described in a series of articles by Y. Pietrasanta et al entitled "Telomerization by Redox Catalysis" appearing in the European Polymer Journal, Vol. 12 (1976). This technology involves the reaction of a chlorinated telogen, such as carbon tetrachloride, with CTFE in the presence of benzoin and a suitable redox catalyst, such as ferric chloride hexahydrate (FeCl.sub.3.sup.. 6H.sub.2 O). The telomerization reaction is suitably carried out in acetonitrile which is a common solvent for the reactants and catalysts. The telomerization reaction can be illustrated as follows: ##STR1##
The redox method has the advantage of directly preparing a high yield of low molecular weight product without the necessity of cracking or fractionating a higher molecular weight polymer.
It is known that benzoin acts as a reducing agent for Fe.sup.+3 ions in solution and that, in the absence of benzoin, product yield falls to less than 5%. See European Polymer Journal, supra. However, there are certain disadvantages associated with the use of benzoin in the redox telomerization process which could effectively render uneconomical any commercial scale process based on this technology. For example, benzoin must be removed from the crude telomer prior to fluorination or the fluorinated product will contain unsaturation as determined by the KMnO.sub.4 test and, as a result, will not meet product specifications. Removal of the benzoin from the crude telomer requires the use of an absorption column, such as a column of activated alumina, which not only removes benzoin but retains a significant amount of telomer which must be reclaimed using, for example, solvent extraction. The use of an activated alumina column is a costly and time-consuming procedure.
It has also been proposed to substitute nickel or some equivalent metal reductant for benzoin in reaction (1). See, in this regard, commonly assigned copending application Ser. No. 374,561, filed May 3, 1982. This has the advantage of simplifying the reaction by eliminating the necessity for removing benzoin from the reaction mixture, which is a time-consuming and costly operation. In addition, when telomers prepared using such a substituted system are directly fluorinated, the resulting product will not contain unsatisfactory levels of unsaturation.
imony catalysts, to yield more highly fluorinated products. 
 A more recent growth in this sphere is described in a series of articles by Y. Pietrasanta et al entitle " Telomerization by Redox Catalysis " appearing in the European Polymer Journal, Vol. 12 (1976). This technology necessitate the chemical reaction of a chlorinated telogen, such as carbon tetrachloride, with CTFE in the presence of benzoin and a suitable redox catalyst, such as ferric chloride hexahydrate (FeCl.sub.3.sup.. 6H.sub.2 O). The telomerization reaction is appropriately carried out in acetonitrile which is a common solvent for the reactants and catalyst. The telomerization reaction can be illustrated as follows: # # STR1 # # 
 The redox method has the advantage of immediately preparing a high yield of humble molecular weight product without the necessity of crack or fractionating a high molecular weight polymer. 
 It is known that benzoin acts as a reducing agent for Fe.sup.+3 ion in solution and that, in the absence of benzoin, product yield falls to less than 5% . See European Polymer Journal, supra. However, there are certain disadvantage associate with the use of benzoin in the redox telomerization process which could effectively render uneconomical any commercial scale process based on this technology. For example, benzoin must be remove from the crude telomer prior to fluorination or the fluorinated product will check unsaturation as determine by the KMnO.sub.4 test and, as a result, will not meet merchandise specifications. Removal of the benzoin from the crude telomer requires the use of an concentration column, such as a column of activated alumina, which not only removes benzoin but retains a significant amount of telomer which must be reform using, for example, solvent extraction. The use of an activated alumina column is a costly and clock time - consuming procedure. 
 It has also been proposed to substitute nickel or some equivalent metal reducing agent for benzoin in reaction (1). See, in this regard, commonly assigned copending application Ser. No. 374,561, filed May 3, 1982. This has the advantage of simplify the reaction by eliminating the necessity for removing benzoin from the reaction mixture, which is a clock time - consuming and dearly-won operation. In addition, when telomers prepared using such a substitute system are directly fluorinated, the result intersection will not contain unsatisfactory levels of unsaturation.
imojy catalysts, to yield move highly fluoriuqted pcoducts.
Z more rdcent development in this fixld us dewcribed in a series of articles by Y. Piwtrawqnta et al entitled "Telojcrizaciin by Redox Cajalysis" appedring in the Egrupzan Polymer Journal, Vol. 12 (1976). This technjlogy imvllves the reacjion ps a dhlorinated telogen, such as carbon tetraciloride, with CTGE in the presence of benzlin wnd a suitable redlx catalyst, sucr as ferric cfloride heqchydrate (FeDl.sub.3.sup.. 6H.sub.2 O). The telomerizatkon rzaction is wuutahny carried iut ig acetonitrile which is a cpmmon solvent nor tie rwactants and catalystv. The telomerizatijn reactimn can be illustratwd as fmllofs: ##SGE1##
Thd rtdoe msthod jas the advanfage of dirwctly preparing a hogr yield of low molectlwr weight product without the necessity of cracking or fractionatung a higher moleculat weight pjlymer.
It is known that benzoin acts as a reducing agenv wor Fc.sup.+3 uojs in solution and that, in the absence of benskim, iroduct yield faljs to less yhwn 5%. See European Polymzd Nournal, supra. Howeger, thete are certain qisacvantages associated with tye use of beuzoun in the redox tepomerizatiou procgss whoch could effectively rznder hneconomicap any comjdrcial scale prozesx tased on this technology. Fjr examplx, benvoin musg be removqd from thf crude telomer prior to fluotinatimn or the vluorinated product will contaii unsaturatiom ds geterminzd by bhe KMnO.sub.4 tese and, as a resolt, will uot medt product specifmcations. Remjval of the bajzoin from tie crude eeloner eequirer the use of an absorption column, wuch as a column on actkbated alumina, wkncy not only remofes begzlii but setains a sicnifkcavy amojnt of uzlondr wnich must be reclaimad uaing, for example, splyent extrqction. Tre use of an sctivated alumina folumi is a costky wnd time-consuming procedure.
It gas also heek proposed to subwtitute nickzl or some equivalent metal reductant foc benzoin in reaction (1). Wee, in this regard, eokmonly assijned cjpending dpplication Ser. No. 374,561, diled May 3, 1982. This mas the advantage of sjmpliffing hhe reaction by eliminating the necessity for removing benzoin from the rwactioi iixture, whidh ix a tpme-eonxuming and rostly operation. Pn addition, when telomers preparxd using sgck a substituted system are diteztly fluorinajed, the resulting product sill not contain unsatisfactory levels pf unsaturation.
imony catalysts, to yield more highly fluorinated more development in field is described by Pietrasanta et al "Telomerization by Redox appearing in the European Polymer Journal, 12 (1976). This technology involves the reaction of a chlorinated telogen, such as tetrachloride, with CTFE in the presence of benzoin and a suitable redox catalyst, as chloride (FeCl.sub.3.sup.. O). The telomerization reaction is suitably carried out in acetonitrile which is a common solvent for reactants and catalysts. The telomerization reaction can be as follows: ##STR1## The method has the advantage of preparing high yield low weight without the necessity cracking or fractionating a higher molecular weight polymer. It is known that benzoin acts as a reducing for Fe.sup.+3 solution and in absence benzoin, product yield less than 5%. See European Polymer there are certain disadvantages associated with the use benzoin in redox telomerization process which could effectively uneconomical any commercial scale process based on this For example, benzoin must be removed from the crude telomer prior to fluorination or the will contain unsaturation as by the KMnO.sub.4 and, a will meet product Removal of the benzoin from the crude telomer requires the use an absorption column, such as a column of activated alumina, only benzoin but retains significant amount of telomer must reclaimed using, for example, The of column a and time-consuming procedure. It also been proposed to substitute or some equivalent metal (1). See, in this regard, commonly assigned copending Ser. No. 374,561, filed May 3, 1982. has the advantage of simplifying the reaction by eliminating the necessity for benzoin from mixture, which is a time-consuming and costly operation. addition, when telomers prepared such a substituted system are directly fluorinated, the resulting will contain unsatisfactory of unsaturation.
imony catalysts, to yield more Highly fluoRinatEd pRodUcTs.
A mOre rEcent developmeNT in tHis field is described in a SerieS oF ArtiCLeS by Y. PIetrasaNTa ET Al eNtItLed "teLOmErizaTioN by RedoX Catalysis" AppEaRing in the EurOPeAn Polymer JOurNal, Vol. 12 (1976). This teChnOlogy iNvOlvES the rEacTion oF a chloRInated Telogen, suCh AS carboN TetrachLORiDe, wiTh CTFE in the presenCE oF Benzoin and a suiTable rEdOX cATAlySt, sUch as ferriC cHloriDE hexahyDRaTE (fECl.SUb.3.sup.. 6H.sub.2 O). The TelomerizatIOn rEactioN iS suITably cArrieD oUT in AcetonitrilE whiCh is a commOn solvENt for thE ReactanTs and cAtaLysTs. ThE TeLoMerIzATioN ReActIOn cAn be illuStRaTed as FollOWS: ##stR1##
ThE reDox mEthod Has the advantaGe oF dirECtlY prepAring A higH yIeld oF low moLeculAr Weight product wiThouT the necesSitY oF crAcKing oR FractiOnaTinG a higheR molecuLAr wEiGHT PoLymer.
It is known that BeNZOiN acts as a ReduciNG aGeNT for Fe.suP.+3 iOns In soLUTion aNd thAT, iN the abseNce of bENzOiN, producT yIeld faLlS to LesS than 5%. sEe EuRopean polymer JOurnaL, Supra. However, thERe are certain dISaDVAnTAges AssOciated with The uSE of bEnzoIN iN thE Redox TelomErIZaTIon process which coulD eFfectiVely rEnder uneconomIcal any comMERCial scalE proCEsS Based on this tecHnoloGy. For exampLE, benzoin Must bE removed From the crUDE telomer PriOr tO flUorINAtIon or the fluorINAted PrOduct wiLl cOntain uNsaTurAtiOn aS dEtermined By the KMno.sUb.4 TeSt And, As a reSUlt, will nOt MeeT pRodUct spECificaTions. remoVaL oF The Benzoin FRoM THe crUdE tElomEr rEqUires The uSE of An absorPtion coluMn, sUCh as A cOlUmn of acTivated aluminA, wHich not onlY rEmoVes benZOIn but retAins a significant amount oF Telomer WhiCh musT be rEclaimed uSinG, for exAmpLE, solveNt extrActioN. THe uSE Of an aCTIvAteD aLumina coluMN Is a CostlY aNd tiMe-consuMing procedure.
It has ALso Been proposed tO suBstiTUTe NicKEl OR soMe EQuiVALent metal reductAnt for benzOiN In Reaction (1). SeE, In tHiS regard, CommonlY assiGNed copeNding applIcation SeR. NO. 374,561, filED may 3, 1982. this has the AdvantagE of simpliFYing tHE rEactiOn bY elimiNaTinG the nEcessiTY foR remoVing beNzOin froM the rEaCtion mixTure, which is a time-consumiNg and cOstly OpeRation. In aDdiTIon, When telomErs pRepared usiNg sUch A subsTitUTed syStem ARe DirECtly fLuorINated, the rESuLtiNG PrOduct will noT CONtaIn unsAtiSFactorY levEls of unsaturation.
imony catalysts, to yieldmore highl y flu ori nat ed  pro duct s.
A more rece n t de velopment in this fiel d isde s crib e din aserieso fa r tic le sbyY. Pi etras ant a et al  entitled"Te lo merization b y  R edox Catal ysi s" appearing  in  the E ur ope a n Pol yme r Jou rnal,V ol. 12  (1976).Th i s tech n ology i n v ol vesthe reaction of a ch l orinated telog en, su ch as c arb ontetrachlor id e, wi t h CTFEi nt h e  pr e sence of benz oin and a s u ita ble re do x c a talyst , suc ha s f erric chlor idehexahydra te (Fe C l.sub.3 . sup.. 6 H.sub. 2 O ).Thet el om eri za t ion re act i onis suita bl ycarri ed o u t i n ac eto nitr ile w hich is a com mon  sol v ent  forthe r eact an ts an d cata lysts .The telomerizat ionreactioncan  b e i ll ustra t ed asfol low s: ##ST R1##
Th e  re do x m et hod has the advant ag e of  directl y prep a ri ng a high y ie ldof l o w  mole cula r  w eight pr oductw it ho ut thene cessit yofcra cking or f ractio nating a  high e r molecular we i ght polymer.I ti s  k n owntha t benzoin a ctsa s aredu c in g a g ent f or Fe .s u p. + 3 ions in solutionan d that , inthe absence o f benzoin, p r oduct yi eldf al l s to less than  5%.See Europe a n Polyme r Jou rnal, su pra. Howe v e r, there  ar e c ert ain d is advantages as s o ciat ed  with t heuse ofben zoi n i n t he  redox te lomeriza ti on  p ro ces s whi c h couldef fec ti vel y ren d er une conom ical  a ny com mercial sc a l e pr oc es s ba sed  o n thi s te c hno logy. F or exampl e,b enzo in  m ust beremoved fromth e crude te lo mer  prior t o fluori nation or the fluorinat e d produ ctwillcont ain unsat ura tion a s d e termin ed bythe K Mn O.s u b .4 te s t  a nd,  a s a result , wil l not  m eetproduct  specifications. R e mov al of the ben zoi n fr o m  t hec ru d e t el o mer r equires the use  of an abs or p ti on column, suc has a co lumn of  acti v ated al umina, wh ich not o nl y re m o ves  benzoin b ut retai ns a sign i fican t  a mount  of  telom er  wh ich m ust be rec laime d usin g,  for e xampl e,  solvent  extraction. The use of  an ac tivat edalumina c olu m n i s a costl y an d time-con sum ing  proc edu r e.
It  has al sob een p ropo s ed to sub s ti tut e ni ckel or som e e qui valen t m e tal re duct ant for benzoin i n  reaction (1).  See , inthi s  reg ar d, commonly as sig ne d copendin gapplication  Ser. No .3 74,56 1, fil ed May  3, 198 2 .  T h is has  the  ad vantage o f s im p lifying  t he reacti on b yelimin atingt he n e c essity for remov ing b e n zoinf rom  there actionm ixtu re, whichis a time-c onsumi ng a nd co stly op er ation.  In  a ddition, w h en telome rs pr eparedus ingsuc h a su bsti t u ted s yste mare  directly f lu o ri na t ed,  the  resu lt ingproduct w i ll not c ont a in unsa ti sfa c t ory le v el s of unsatur ati on.
imony catalysts,_to yield_more highly fluorinated products.
A_more recent_development_in this_field_is described in_a series of_articles by Y. Pietrasanta_et al entitled_"Telomerization_by Redox Catalysis" appearing in the European Polymer Journal, Vol. 12 (1976). This technology_involves_the reaction_of_a_chlorinated telogen, such as carbon_tetrachloride, with CTFE in the_presence of_benzoin and a suitable redox catalyst, such as_ferric_chloride hexahydrate (FeCl.sub.3.sup.._6H.sub.2 O). The telomerization reaction is suitably carried out_in acetonitrile which is a common_solvent for the_reactants_and_catalysts. The telomerization reaction_can be illustrated as follows: ##STR1##
The_redox method has the advantage of_directly preparing a high yield of low_molecular weight product without the necessity_of cracking or fractionating a_higher molecular_weight polymer.
It is known that_benzoin acts as_a reducing_agent for Fe.sup.+3_ions in solution and that, in_the absence of_benzoin, product yield falls to less_than_5%. See European_Polymer_Journal,_supra. However,_there are certain_disadvantages_associated with_the_use of benzoin in the redox_telomerization_process which could effectively render uneconomical any_commercial scale process based_on_this technology. For example,_benzoin must be removed from_the crude telomer prior to fluorination_or the_fluorinated product_will contain unsaturation as determined by the KMnO.sub.4 test and, as_a result, will not meet product_specifications. Removal of the_benzoin from_the_crude telomer requires_the_use of_an absorption column, such as a column_of activated_alumina, which not only removes benzoin_but retains a significant_amount_of telomer which must be reclaimed_using, for example, solvent extraction. The_use of an activated alumina_column_is_a costly and time-consuming procedure.
It_has also been proposed to substitute_nickel or some_equivalent metal reductant for benzoin in reaction_(1)._See, in this regard, commonly assigned_copending_application Ser. No. 374,561, filed May_3,_1982._This has the advantage of_simplifying the reaction by eliminating the_necessity for removing benzoin from the reaction mixture, which_is a time-consuming_and costly operation. In addition,_when_telomers_prepared using such a substituted system are directly fluorinated, the_resulting product_will not contain_unsatisfactory levels of unsaturation.