Conformational Study of the Intramolecular Diels−Alder Reaction of a Pentadienyl Acrylate. Theoretical Evaluation of Kinetic and Thermodynamic Control

Abstract

Acrylate 4, prepared from diacetylrhamnal, underwent intramolecular Diels-Alder cycloaddition to give the thermodynamically disfavored trans-fused gamma-lactone 15 as the major product, along with two stereoisomeric cycloadducts. A computational analysis of each of the four transition states arising from 4 and the corresponding cycloadducts permits an understanding of the contrasting requirements for kinetic versus thermodynamic control of the reaction.