Simple and Efficient Synthesis of α-Allenic Alcohols and Their Novel Conversion into 1-Aryl-3-formyloxy-1,3-butadienes

Reactions of carbonyl compounds with 3-bromo-1-propyne in the presence of SnCl2·2H2O and LiI·3H2O gave α-allenic alcohols in moderate yields together with small amounts of β-acetylenic alcohols. The α-allenic alcohols can be converted into 1-aryl-3-formyloxy 1,3-butadienes, novel 1,3-butadiene derivatives.