Improved Procedure for the Preparation of cis‐2,4‐Dimethylglutaranhydride

Abstract

Addition of 2.5 mol% DBU to a mixture of isomeric 2,4‐dimethylglutaric anhydrides in ethyl acetate promotes crystallization‐induced transformation, affording the pure cis‐2,4‐dimethylglutaric anhydride in 87% yield.

Keywords:

• Crystallization
• DBU
• 2,4‐dimethylglutaric anhydride
• isomerization

Acknowledgment

The author is grateful to Professor Pierre Potier (deceased on February 3, 2006), Professor Jean‐Yves Lallemand and Dr. Jean Boivin (Institut de Chimie des Substances Naturelles) for their kind hospitality, and to Dr. Mikhail Ermolensko and Dr. Emmanuel Roulland for stimulating discussions.