Luche Reaction

Abstract

Abstract The modification of the initial aqueous allylation of carbonyl compounds via the intermediacy of tin in the presence of a catalytic amount of hydrobromic acid, to the zinc mediated allylation of carbonyl compounds using ultrasonic irradiation in saturated aqueous NH 4 Cl/THF solution. Hence, the new reaction condition is referred to as the Luche reaction. The study finds that ammonium chloride is often added to the reaction media to activate the metal surface so that the yield can be enhanced. For the reaction between aldehyde and bromopropenyl methylcarbonate to give the rearranged allyl methylcarbonate, it has been found that a mixture of diastereomers are obtained, and the ratio of syn / anti depends on the nature of the aldehyde. In addition it has been reported that when a zinc‐copper couple is used, alkyl halide reacts with α,β‐unsaturated carbonyl compounds and nitriles via a conjugate addition. Besides zinc, some other metals have also been applied to facilitate the aqueous allylation of carbonyl compounds.