Cp*Rh(iii)/boron hybrid catalysis for directed C-H addition to -substituted ,-unsaturated carboxylic acids

The C-H bond addition reaction of 2-phenylpyridine derivatives with alpha,beta-unsaturated carboxylic acids catalyzed by Cp*Rh(iii)/BH3 center dot SMe2 is reported. Activation of C-H bonds with the rhodium catalyst and activation of alpha,beta-unsaturated carboxylic acids with the boron catalyst cooperatively work, and a BINOL-urea hybrid ligand significantly improved the reactivity. With the optimized hybrid catalytic system, various beta-disubstituted carboxylic acids were obtained under mild reaction conditions.