Visible Light-Induced EDA-Complex Triggered Annulative Difunctionalization via Olefin-Olefin Coupling and Radical Truce-Smiles Rearrangement

Abstract

An EDA complex comprising N-allyl bromodifluoroacetamides and tertiary alkyl amine was exploited to facilitate annulative difunctionalization reaction under visible-light irradiation. This external photocatalyst-free methodology garners olefin-olefin coupling featuring a radical Truce-Smiles rearrangement and produced long-chain functionalized gem-difluoropyrrolidones from N-substituted methacryloyl sulfonamides, while simple N-aryl methacrylamides furnished pyrrolidinone-oxindole hybrid lactams in high yields. Mechanistic investigations substantiate a combined reaction mechanism, involving charge-transfer EDA complex-based radical cascade, alongside an α-aminoalkyl radical-triggered XAT process, exhibiting a quantum yield value of 1.48.