Nickel‐Catalyzed Mizoroki–Heck‐Type Reactions of Unactivated Alkyl Bromides.

The development of a general, nickel‐catalyzed alkyl‐Mizoroki–Heck reaction of unactivated alkyl bromides is described. The mild reaction proceeds efficiently using a wide range of primary and secondary alkyl bromides, and examples of intermolecular cross‐couplings are provided. Reaction alkene regioselectivity is significantly enhanced over prior carbocyclizations using palladium catalysis. Mechanistic investigations are consistent with a direct carbocyclization in contrast to the auto‐tandem atom‐transfer cyclization and halide elimination previously observed with palladium catalysis. [ABSTRACT FROM AUTHOR]