Origin of Stereochemistry in Simple Pyrrolidinone Enolate Alkylations

摘要

It now appears that we have been successful in isolating a heretofore unappreciated electronic effect involving facial (syn or anti) alkylation of a nitrogen-containing enolate. The nitrogen lone pair has been shown by both experiment and calculation to facially bias the electronic character of the π-system in enolates 8, a phenomenon earlier considered by Eschenmoser.