Visible-light-mediated minisci C–H alkylation of heteroarenes with 4-alkyl-1,4-dihydropyridines using O2 as an oxidant†
Abstract
Herein, we report a protocol for direct visible-light-mediated Minisci C–H alkylation reactions of N-heteroarenes with 4-alkyl-1,4-dihydropyridines at room temperature with molecular oxygen as an oxidant. The protocol permits efficient functionalization of various N-heteroarenes with a broad range of cyclic and acyclic primary, secondary, and tertiary alkyl groups and is scalable to the gram level. This mild protocol uses an inexpensive, green oxidant and is suitable for late-stage C–H alkylation of complex nitrogen-containing molecules. We demonstrated its utility by preparing or functionalizing several pharmaceuticals and natural products.