The Allylic Rearrangement. IV. New Synthesis of 4-Hexenoic Acid

Abstract
rans-4-Hexenoic acid, a useful starting material for the synthesis of racemic 4R : 5S and 4S : 5R 4,5-dihydroxyhexanoic acid γ-lactone, one component of the aroma extracts from one Galifornian and two Spanish flor sherries, has been conveniently prepared by the Favorskii-type rearrangement of 5-chloro-3-hexen-2-one.