Chiral Cp-rhodium(III)-catalyzed asymmetric hydroarylations of 1,1-disubstituted alkenes

Abstract

Metal-catalyzed functionalizations at the ortho position of a directing group have become an efficient bond-forming strategy. A wide range of transformations that employ Cp*Rh(III) catalysts have been described, but despite their synthetic potential, enantioselective variants that use chiral versions of the Cp* ligand remain scarce (Cp*=pentamethyl cyclopentadienyl). Cyclopentadienyl compounds with an atropchiral biaryl backbone are shown to be suitable ligands for the efficient intramolecular enantioselective hydroarylation of aryl hydroxamates. Dihydrofurans that bear methyl-substituted quaternary stereocenters are thus obtained by CH functionalization under mild conditions.

Keywords: CH activation; asymmetric catalysis; cyclopentadienyl ligands; hydroarylation; rhodium.