Benzophenothiazine and Its Cr(III)-Catalyzed Cross Dehydrogenative Couplings.

In stark contrast to phenothiazines and their prevalence for cross-dehydrogenative amination reactions, benzophenothiazine has a pronounced preference for cross-dehydrogenative C-C bond-forming reactions. Moreover, the substrate is very versatile, leading to several new classes of C-C bond-forming reactions and many new oxidative coupling product architectures, including unprecedented indole fused paddlewheel-like structures.