Lewis Acid-Mediated Isothiocyanation and Chlorination of Quinoxalin-2(1)-ones under Visible Light Conditions.

Lewis acid-mediated selective C3-isothiocyanation of quinoxalin-2(1)-ones using -thiocyanatosaccharin as an isothiocyanate source under visible light conditions at room temperature is described. Under similar conditions with -chlorosaccharin, the C3-chlorination of quinoxalin-2(1)-ones achieved a 2 h time frame. Good to an excellent yield of products was obtained in both cases with broad functional group tolerance.