Abstract

Mixtures of (EE)-2-methyl-1-silyloxypenta-1,3-dienes, enoxysilanes, SO2 and (t-Bu)Me2SiOTf (catalyst) generate (Z)-5-alkyl-1,3-dimethyl-6-oxo-4-silyloxyalk-2-enesulfinic acids that undergo stereoselective retro-ene eliminations of SO2 with the formation of corresponding (E)-3-hydroxy-2-alkyl-4-methylalk-5-en-1-ones with 2,3-syn and 3,4-anti diastereoselectivity. (C) 1997 Elsevier Science Ltd.

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