Heterocycle Synthesis via High-Valent Cobalt-Catalyzed C-H Activation

Heterocycle Synthesis via High-Valent Cobalt-Catalyzed C-H Activation 

Grigorjeva and Daugulis further extended the scope of the cobalt catalysis of 8-aminoquinoline benzamide to achieve oxidative carbonylation 

Heterocycle Synthesis via C-H Functionalization under Co(ll)-Based Metalloradical Catalysis 

C-H alkylation and amination reactions involving metal-carbenoid and metal-nitrenoid species have been developed for many years, most extensively with (chiral) dirhodium(ll) carboxylate and carboxamidate complexes as catalysts [45]. When performed in intramolecular settings, such reactions offer versatile methods for the (enantioselective) synthesis of hetero- and carbocy-cles. In the past decade, Zhang and coworkers had explored the catalysis of cobalt(II)-porphyrin complexes for carbene- and nitrene-transfer reactions [46] and revealed a radical nature of such processes as a distinct mechanistic feature compared with typical metal (e.g., rhodium)-catalyzed carbenoid and nitrenoid reactions [47]. Described below are examples of heterocycle synthesis via cobalt(II)-porphyrin-catalyzed intramolecular C-H amination or C-H alkylation. 

11212-11222 (b) Patureau, FW, Wencel-Delord, J, and Glorius, F, (2012) Aldrichimica Acta, 

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