Brønsted Acid Enhanced Rhodium‐Catalyzed Conjugate Addition of Aryl CH Bonds to α,β‐Unsaturated Ketones under Mild Conditions

Acid test: With a Brønsted acid as the solvent, the rhodium-catalyzed direct addition of aryl CH bonds to α,β-unsaturated ketones was realized under mild reaction conditions (see scheme). The acid may assist by interceding in the conflict of the two proton-transfer events and averting the substrate inhibition involved in this type of CH addition reaction.