A Convenient Synthesis ofα-Halomethylene Aldols orβ-Halo-α-(hydroxyalkyl)acrylates Using the Chalcogeno-Baylis-Hillman Reaction

Abstract

Alkynes are the substrates in a dimethyl sulfide catalyzed chalcogeno-Baylis–Hillman reaction involving titanium halides (see scheme). α-Halomethylene aldols or β-halo-α-(hydroxyalkyl)acrylates can be prepared readily and diastereoselectively (E selectivity for the former and Z selectivity for the latter).