Iron-Catalyzed Directed Alkylation of Carboxamides with Olefins via a Carbometalation Pathway

Abstract

A catalytic amount of an iron salt and bipyridine ligand in the presence of an organozinc base activates the ortho C–H bond of a carboxamide, and the following reaction with an alkene such as ethylene gas (1 atm), styrene derivatives, and vinylsilane or vinylboron derivatives via carbometalation gives a putative alkylzinc intermediate. This intermediate can be further reacted with electrophiles such as deuterium oxide or allyl bromide. When monosubstituted alkenes are used as a substrate, the linear alkyl product is selectively obtained. The monoalkylated product is exclusively obtained, and dialkylation does not proceed.