Visible-light-promoted organic-dye-catalyzed sulfonylation/cyclization to access indolo[2,1-a]isoquinoline derivatives

]isoquinoline derivatives were obtained in moderate to good yields. Mechanistic studies indicate that a sulfonyl radical pathway is involved in this reaction. Compared with previous works, this protocol has the advantages of being metal- and base-free, using visible light as a traceless energy source, simple operation and mild reaction conditions, all of which make this methodology more attractive.