Evidence for syn stereochemistry in intramolecular SN′ reaction of allylic acetates
Abstract
Reaction of the anion of the (R*,S*) and (R*,S*) isomers of dimethyl (E-5-acetoxyhex-3-en-2-yl)malonate [(R*,R*)-(1) and (R*,S*)-(1)] in refluxing dimethoxyethane results in an intramolecular SN′ reaction, where the displacement of the acetate by the carbanion proceeds with syn stereochemistry (94–96%syn).