ChemInform Abstract: Highly Stereoselective Reduction of Chiral α-Keto-β,γ-Unsaturated Acetals: Synthesis of Both Epimeric Allyl Alcohols by Proper Choice of Additive.

ChemInform Abstract

Reduction of the chiral α-keto β,γ-unsaturated acetals (I) yields the diastereomeric hydroxy acetals (II) and (III). The use of lithium aluminum hydride in the presence of lithium bromide results in the predominance of the isomers (II). When magnesium bromide is employed as the additive, the compounds (III) are the main products. The influence of other reducing agents or additives is investigated.