Radical Stabilization Algorithm as a Predictive Tool for Novel and Reported Noncanonical Thiele’s Acid Analogues

This paper is dedicated to Professor Victor Snieckus, in honour of his 80^th birthday

Abstract

We recently showed that a simple radical-stabilization algorithm outperformed traditional frontier-molecular orbital methods for rationalizing the outcome of the venerable Thiele’s acid (or ester) Diels–Alder dimerization. In the present Communication, we describe a novel noncanonical Thiele-type dimerization of a cyclopentadiene phosphine oxide, and show that when steric factors are taken into account the ­radical-stabilization method once again correctly rationalizes the regio­chemical outcome for the reaction. We further show that the method appears to be general for all known Thiele- and half-Thiele dimerization events.

Key words

Diels–Alder reaction - Thiele’s acid - predictive methods for cycloadditions

• References and Notes

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