A Stereoselective Oxy-Michael Approach to THP*-Protected β-Hydroxy Esters

Abstract

The ‘naked’ anion of (S)-6-methyl δ-lactol undergoes efficient oxy-Michael addition to α,β-unsaturated methyl sulfones to give the corresponding adducts with excellent (up to 99% de) stereo­control at the newly formed stereogenic β-centre. The successive reductive desulfonylation using excess samarium(II) iodide under mild reaction conditions affords the THP*-protected β-hydroxy esters as single diastereoisomers after chromatography on silica gel.

asymmetric synthesis - oxy-Michael additions - samarium(II) iodide - protodesulfonylation - β-hydroxy esters

References

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