Crossed Cannizaro reaction: Mechanism evaluation by HPLC analysis of products

CHED 369

Jillian E. Hostetter, dball@csuchico.edu and Don B. Alger, dalger@csuchico.edu. Department of Chemistry, California State University, Chico, Chico, CA 95929-0210
The crossed Cannizzaro reaction involves the reaction of a mixture of two aldehydes with no alpha hydrogens and produces a mixture of two alcohols and two acids. Based on the widely accepted mechanism, and expected influences of inductive, steric and resonance effects, one might expect to be able to predict which aldehyde would be preferentially oxidized. Benzaldehyde was used with either ortho, meta or para-tolualdehyde. In order to evaluate the validity of predictions. It was necessary to develop analytical procedures using HPLC to analyze the mixtures of alcohols and acids. Evaluation of the importance of homogeneity in the reaction was also attempted.