Potassium organotrifluoroborates: new partners in catalytic enantioselective conjugate additions to enones

Potassium organotrifluoroborates, highly stable organoboron derivatives and easily accessible from organolithiated reagents, can achieve rhodium(I)-catalyzed asymmetric 1,4-additions to enones using binap as chiral ligand. This reaction proceeds in nearly quantitative yields to afford β-functionalized ketones with e.e. up to 98%.