Access to SCF3 substituted indolizines via a photocatalytic late-stage functionalization protocol

A mild, scalable, and highly chemoselective photocatalytic method was developed for the direct indolizine functionalization with N-((trifluoromethyl)thio)saccharin, yielding high amounts of desired products while tolerating various functional groups. The photoredox catalyst employed offers a straightforward and inexpensive alternative to commercially available catalysts. Additionally, a 3-SCF₃ analogue of a histamine H3 receptor antagonist was synthesized with excellent yield, demonstrating the strategy’s potential in developing biologically relevant molecules. Methods All NMR-Data FID files were recorded by either a BRUKER Digital AVANCE 400 MHz FT-NMR or a BRUKER Digital AVANCE III 600 MHz FT-NMR.