to exposure to the reaction conditions, or the crude material can be immediately subjected to oxidation without isolation. Both acyclic and cyclic silyl enol ether derivatives can be prepared in this way and subsequently be used as substrates in the Rubottom oxidation. Below are some representative Rubottom oxidation products synthesized in the seminal papers. In 1978, Rubottom showed that siloxy 1,3 dienes, derived from acyclic or cyclic enones could also serve as substrates for the Rubottom oxidation to forge α-hydroxy enones after treatment with triethyl ammonium fluoride. These substrates give a single regioisomer under the reaction conditions due to the electron-rich nature of the silyl enol pi-bond (See synthesis of Periplanone B below). Modifications and improvements The Rubottom oxidation has remained largely unchanged since its initial disclosure, but one of the major drawbacks of standard conditions is the acidic environment, which can lead to unwanted side reactions and degradation. A simple sodium bicarbonate buffer system is commonly employed to alleviate this issue, which is especially problematic in bicyclic and other complex molecule syntheses (see synthetic examples). The introduction of chiral oxidants has also allowed for the synthesis of enantiopure α-hydroxy carbonyl derivatives from their corresponding silyl enol ethers. The first example of an enantioselective Rubottom oxidation was published by F.A. Davis in 1987 and showcased the Davis chiral oxaziridine methodology (Davis oxidation) to give good yields but modest enantiomeric excesses. In 1992, K.B. Sharpless showed that the asymmetric dihydroxylation conditions developed in his group could be harnessed to give either (R)- or (S)- α-hydroxy ketones from the corresponding silyl enol ethers depending on which Chinchona alkaloid-derived chiral ligands were employed. The groups of Y. Shi and W. Adam published another enantioselective variant of the Rubottom oxidation in 1998 using the Shi chiral ketone in the presence of oxone in a buffered system to furnish α-hydroxy ketones in high yield and high enantiomeric excess. The Adam group also published another paper in 1998 utilizing manganese(III)-(Salen)complexes in the presence of NaOCl (bleach) as the oxidant and 4-phenylpyridine N-oxide as an additive in a phosphate buffered system. This methodology also gave high yields and enentioselectivities for silyl enol ethers as well as silyl ketene acetals derived from esters. Along with chiral oxidants, variants of mCPBA have been examined. Stankovic and Espenson published a variation of the Rubottom oxidation where methyltrioxorhenium is used as a catalytic oxidant in the presence of stoichiometric hydrogen peroxide.