Iron-catalyzed cyanomethylation of 4H-pyrido[1,2-a]pyrimidin-4-ones and quinolin-4(1H)-ones with alkyl nitriles.

An iron(iii)-catalyzed C3-selective cyanomethylation of 4H-pyrido[1,2-a]pyrimidin-4-ones and quinolin-4(1H)-ones has been developed using alkyl nitriles as a cyanomethyl source. This protocol exhibits broad substrate scope and good functional-group tolerance, affording the corresponding C3-(hetero)arylacetonitriles in good to high yields. The reaction proceeds under mild oxidative conditions with di-tert-butyl peroxide (DTBP) and involves the generation of a cyanomethyl radical, enabling direct C-H functionalization without substrate pre-activation.