Visible-light-induced deoxygenative C2-sulfonylation of quinoline N-oxides with sulfinic acids

The first example of visible-light-induced deoxygenative C2-sulfonylation of quinoline N-oxides with sulfinic acids in the presence of an organic dye as the catalyst was developed. The reaction conditions are eco-friendly and mild, employing ambient air as the sole oxidant and aqueous acetone solution as the solvent. This approach requires only a very low catalyst loading, allowing gram-scale preparation as well as late-stage modification of biologically active compounds bearing quinoline groups.