Thioamidate Ion as Effective Cocatalyst for Photoinduced C–H Alkylation via Multisite Proton-coupled Electron Transfer

Thioamidate ions are introduced as competent cocatalysts for multisite proton-coupled electron transfer (MS-PCET) catalysis. The effectiveness of these anions is ascribed to the high pKa values of their conjugate acids. The combined use of bench-stable tetrabutylammonium thioamidate with an appropriate Ir-based photosensitizer allows the C–H alkylation of a range of C–H donors, including simple cyclic alkanes, under visible-light irradiation. Thioamidate ions are introduced as competent cocatalysts for multisite proton-coupled electron transfer (MS-PCET) catalysis. The effectiveness of these anions is ascribed to the high pKa values of their conjugate acids. The combined use of bench-stable tetrabutylammonium thioamidate with an appropriate Ir-based photosensitizer allows the C–H alkylation of a range of C–H donors, including simple cyclic alkanes, under visible-light irradiation.