Nickel‐Catalysed syn‐Selective Arylnickelation and Cyclisation of Ketone/Imine‐Tethered Terminal Alkynes with Arylboronic Acids

Herein we report a syn‐arylnickelative cyclisation with ketone‐ and imine‐tethered terminal alkynes (16 examples) in yields of up to 89 %. The reaction proceeds via a syn‐aryl nickelation of a terminal alkyne followed by cyclisation of the resulting alkenylnickel species onto the ketone or imine. The enantioselective version of this transformation has also been explored with enantioselectivities of up to 83 : 17 er observed.