Mn(III)-Mediated Regioselective 6-endo-trig Radical Cyclization of o-Vinylaryl Isocyanides to Access 2-Functionalized Quinolines

A Mn(III)-mediated radical cyclization reaction of o-vinylaryl isocyanides and arylboronic acids or diphenylphosphine oxides to access various 2-functionalized quinolines under mild conditions was developed. With the introduction of radical stabilizing substituents (e. g. aryl and methyl group) on vinyl group, this reaction provides a regiospecific 6-endo-trig radical cyclization of o-vinylaryl isocyanides, giving a number of structurally unique and biologically potential 2-functionalized quinoline derivatives.