Under visible light irradiation, o-phosphinophenolate functions as an easily accessible photoredox catalyst to activate trifluoromethyl groups in trifluoroacetamides, trifluoroacetates, and trifluoromethyl (hetero)arenes to deliver corresponding difluoromethyl radicals. It works in relay with a thiol hydrogen atom transfer (HAT) catalyst to enable selective defluoroalkylation and hydrodefluorination. The reaction allows for the facile synthesis of a broad scope of difluoromethylene-incorporated carbonyl and (hetero)aromatic compounds, which are valuable fluorinated intermediates of interest in the pharmaceutical industry. The ortho-diphenylphosphino substituent, which is believed to facilitate photoinduced electron transfer, plays an essential role in the redox reactivity of phenolate. In addition to trifluoromethyl groups, pentafluoroethyl groups could also be selectively defluoroalkylated.

N-Aryl amides were synthesized via the manganese-mediated amidation of esters with nitroarenes without the need for additional catalysts or ligands.

o-Phosphinophenolate and o-phosphinothiophenolate are potent photocatalysts with strong reducing ability to activate aryl chlorides and bromides under visible light for borylation, arylation, and phosphorylation. Experimental and theoretical studies revealed that the o-diphenylphosphino substituent results in a narrow optical gap and facilitates intersystem crossing to access triplet states, which promote phenolate and thiophenolate to function as effective visible-light-photoredox catalysts. The results presented herein suggest promising utility of synthetically modified phenolates and thiophenolates as photoredox catalysts.