Nickel-Catalyzed Tandem Dimerization/Hydroheteroarylation of Isoprenes with Heteroarenes

Abstract Herein, we report the first nickel-catalyzed tandem dimerization/hydroheteroarylation of isoprenes with indoles, using a catalytic system consisting of a heteroleptic Ni(II) complex Ni(IPr*OMe)[P(OEt)3]Br2 and a base NaOtBu. This system provides easy access to a range of C2-substituted cyclic monoterpenoid indoles with high regioselectivity under solvent-free conditions. This tandem transformation shows good compatibility with indoles bearing various functional groups, such as esters, acetals, silanes, and boronate esters. The tandem transformation is also applicable to other heteroarenes, including pyrroles, (benzo)thiophenes, (benzo)furans, benzimidazoles, pyrazoles, quinazolones, imidazo[1,2-a]pyridines, and pyridines.