Visible-light-driven 1,2-hydro(cyanomethylation) of alkenes with chloroacetonitrile.

A regioselective 1,2-hydro(cyanomethylation) of unactivated aliphatic alkenes is reported. A cyanomethyl radical is generated from haloacetonitriles. This radical adds onto alkenes to form alkyl radicals, which undergo hydrogen atom transfer from thiol to produce one-carbon-extended nitriles. Furthermore, the alkyl radicals are applied to cascade cyclization.