Silyloxy sulfides

Pummerer Reaction. The reagent transforms sulfoxides in the presence of catalytic amounts of zinc iodide into the corresponding a-silyloxy sulfides (eq 1). Vinyl sulfoxides undergo a Michael-Pummerer type reaction to give y-silyloxy-y-phenylthio esters (eq 2). ... 

HEXAHYDRO - 4a,5 - DIMETHYL - 2(3H) - NAPHTHALE-NONE and 2-TRIMETHYLSILYLOXY-1,3-BUTADIENE AS A REACTIVE DIENE DIETHYL trans -4-TRIMETHYL-SILYLOXY-4-CYCLOHEXENE-1,2-DICARBOXYLATE. Sulfur substitution also continues to be of high interest, and three preparations on sulfide synthesis are included BENZYL SULFIDE DIALKYL AND ALKYL ARYL SULFIDES NEOPENTYL PHENYL SULFIDE and UNSYMMETRICAL DIALKYL DISULFIDES sec-BUTYL ISOPROPYL DISULFIDE. 

The addition of other sulfur nucleophiles was reported by Jacobsen to be catalyzed by the same Cr(salen) complex 1 initially reported for the ARO with TMSNj. Benzyl mercaptan afforded the ring-opened hydroxy sulfides in excellent yield and 59-70% ee [17]. The moderate levels of enantioselectivity were improved by use of the dithiol 5, which afforded mixtures of bishydroxy sulfides in which the ee of the chiral product 6 was substantially enriched (Scheme 5). The sulfide products could be easily elaborated into the free thiols by reductive de-benzylation, providing access to the jl-silyloxy thiol 8 in optically pure form. 

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