Anti-Markovnikov hydroheteroarylation of unactivated alkenes with indoles, pyrroles, benzofurans, and furans catalyzed by a nickel-N-heterocyclic carbene system

Abstract

We report the catalytic addition of C-H bonds at the C2 position of heteroarenes, including pyrroles, indoles, benzofurans, and furans, to unactivated terminal and internal alkenes. The reaction is catalyzed by a combination of Ni(COD)2 and a sterically hindered, electron-rich N-heterocyclic carbene ligand or its analogous Ni(NHC)(arene) complex. The reaction is highly selective for anti-Markovnikov addition to α-olefins, as well as for the formation of linear alkylheteroarenes from internal alkenes. The reaction occurs with substrates containing ketones, esters, amides, boronate esters, silyl ethers, sulfonamides, acetals, and free amines.