Synthesis of Aldehydes by Organocatalytic Formylation Reactions of Boronic Acids with Glyoxylic Acid

Reported herein is a conceptually novel organocatalytic strategy for the formylation of boronic acids. New reactivity is engineered into the alpha-amino-acid-forming Petasis reaction occurring between aryl boronic acids, amines, and glyoxylic acids to prepare aldehydes. The operational simplicity of the process and its ability to generate structurally diverse and valued aryl, heteroaryl, and alpha,beta-unsaturated aldehydes containing a wide array of functional groups, demonstrates the practical utility of the new synthetic strategy.