The direct C3 chalcogenylation of indolines using a graphene-oxide-promoted and visible-light-induced synergistic effect

A new and efficient method for the C3-chalcogenylation of indolines, employing visible light irradiation, and graphene oxide as a promoter, at room temperature has been achieved. The features of the reaction include the use of metal-free and iodine-free conditions, simple operation, high yields, the use of a non-toxic and easy-to-handle oxidant, and gram-scalable synthesis. This benign protocol allows access to a wide range of 3-arylthioindoles, 3-arylselenylindoles, and even 3-thiocyanatoindoles in good to excellent yields.