Unexpected reactions of organozinc reagents with N-acylbenzotriazoles

Abstract

Coupling N-acylbenzotriazoles with aliphatic and benzylic organozinc reagents in the presence of zinc bromide / Pd(II) catalyst (or zinc bromide / Ni(0) catalyst) did not result in formation of the expected ketones, but instead gave the corresponding carboxylic acid esters. This reaction apparently occurs by the insertion of oxygen dissolved in the solvent into the organozinc compound.