Stereoselective Michael−Aldol Tandem Reaction of Phenylselenomagnesium Bromide with Acetylenic Sulfones and Aldehydes. An Efficient Synthesis of Polyfunctionalized Allylic Alcohols

A mixture of phenylselenomagnesium bromide, an acetylenic sulfone, and an aldehyde in THF/CH₂Cl₂ afforded Michael−aldol tandem adduct, i.e., (Z)-β-phenylseleno-α-(p-tolylsulfonyl)allylic alcohol, in good yield with high stereoselectivity. The stereoselectivity greatly depended on solvent.