Domino C-H functionalization reactions of gem-dibromoolefins: synthesis of N-fused benzo[c]carbazoles

A palladium-catalyzed domino transformation of gem-dibromoolefins leading to novel polycyclic benzo [c]carbazoles is described. A unique feature of the current reaction is the participation of both bromides in C H functionalization processes. Mechanistic studies were conducted to ascertain the sequence of reaction events, and the results indicate that the (Z)-bromide likely reacts in preference to the (E)-bromide. (C) 2013 Elsevier Ltd. All rights reserved.