Iridium(III) Catalyzed Diastereo- and Enantioselective C−H Bond Functionalization

Iridium(III)-salen complexes were found to efficiently catalyze the enantioselective C−H carbene insertion. The insertion reaction at the α-position of tetrahydrofuran or at the methylene of 1,4-cyclohexadiene proceeded with high enantio- (up to 99%) and diastereoselectivity (up to >20:1 dr; in the former reaction) by using an appropriate combination of complex (1, 2, or 3) and α-diazoacetate (α-aryl-α-diazoacetates or α-diazopropionate) as the carbene source.