An efficient reagent for synthesis of α,β-unsaturated aldehydes 3-methylthio-2-propenyl p-tolyl sulfone

Alkylation of 3-methylthio-2-propenyl p-tolyl sulfone (1) with an alkyl halide and a base (NaH or KOH-TOMAC) took place at the position α to the sulfonyl group to give optionally a mono- or dialkylated product (2 or 3), which was converted to β-monosubstituted or β,β-disubstituted α,β-unsaturated aldehyde (6 or 7), respectively, by TiCl₄-assisted hydrolysis followed by the removal of p-toluenesulfinic acid.