A new paradigm for carbon-carbon bond formation: aerobic, copper-templated cross-coupling.

Thiol esters and boronic acids react to produce ketones under aerobic conditions in the presence of catalytic quantities of a CuI or CuII salt. The reaction occurs at reasonable rates between room temperature and 50 degrees C at neutral pH using thiol esters derived from bulky 2 degrees amides of thiosalicylamides such as those based on N-tert-butyl-2-mercaptobenzamide. In this mechanistically unprecedented reaction system, the carbon-carbon bond formation occurs through templating of the thiol ester and the boronic acid at copper; the system is rendered catalytic in copper under the aerobic conditions.