American Chemical Society
jo7b00044_si_006.cif (21.28 kB)

A Palladium-Catalyzed Ullmann Cross-Coupling/Reductive Cyclization Route to the Carbazole Natural Products 3‑Methyl‑9H‑carbazole, Glycoborine, Glycozoline, Clauszoline K, Mukonine, and Karapinchamine A

Download (21.28 kB)
posted on 2017-02-22, 00:00 authored by Qiao Yan, Emma Gin, Malgorzata Wasinska-Kalwa, Martin G. Banwell, Paul D. Carr
The title natural products 27 have been prepared by reductive cyclization of the relevant 2-arylcyclohex-2-en-1-one (e.g. 20) to the corresponding tetrahydrocarbazole and dehydrogenation (aromatization) of this to give the target carbazole (e.g. 4). Compounds such as 20 were prepared using a palladium-catalyzed Ullmann cross-coupling reaction between the appropriate 2-iodocyclohex-2-en-1-one and o-halonitrobenzene.