Versatile Cp*Rh(III)-Catalyzed Selective Ortho-Chlorination of Arenes and Heteroarenes

The ortho- and monoselective Cp*Rh­(III)-catalyzed chlorination of a broad range of benzene derivatives and electron-rich heterocycles under mild reaction conditions is reported. Inexpensive and commercially available N-chloro-imides could be used as chlorinating agents in as low as substoichiometric quantities. Furthermore, two different reaction protocols were developed to allow for the use of substrates with various electronic properties and enable selective chlorination of a broad range of structural motifs. For electron-rich substrates, the reported protocols enable a perfectly regio-switchable and efficient direct chlorination.