β-Boration of α,β-unsaturated carbonyl compounds in ethanol and methanol catalyzed by CCC-NHC pincer Rh complexes

Quantitative β-boration of α,β-unsaturated carbonyl compounds was achieved utilizing the eco-friendly solvent EtOH along with MeOH at room temperature in 1 h, by a CCC-NHC pincer Rh complex mixture. Substrates with β-substituents were successfully converted yielding challenging, quaternary C–B bonds. The air- and water-stable pre-catalyst A , identified as a mixture of iodo and chloro CCC-NHC pincer Rh amine complexes, was evaluated for catalytic activity. This report is the first example of a pincer Rh complex demonstrating catalytic activity in a 1,4-addition at room temperature.