Photocatalyzed/Base-Mediated Defluorinative Three-Component Cascade Cyclization: Access to Monofluorocyclohexenes and 6-Fluoro-1,2,3,4-tetrahydropyridines.

A three-component cascade cyclization of α-CF3 alkenes, electron-rich alkenes, and dimethyl esters or sulfonamides via a dual C-F bond cleavage process is described. This methodology provides a general and efficient strategy to access monofluorocyclohexenes and 6-fluoro-1,2,3,4-tetrahydropyridines by switching the bifunctional reagents (dimethyl esters or sulfonamides), which are valuable building blocks in synthetic chemistry and the pharmaceutical industries. The reaction mechanism and the synthetic applications of the products have been demonstrated.