Photocatalytic Initiation of Radical Thiol-ene Reactions Using Carbon-Bi2O3 Nanocomposites

A mild, inexpensive, and general photocatalytic initiation protocol for anti-Markovnikov hydrothiolation of olefins using carbon nanomaterial/metal oxide (carbon NM-MO) composites is reported. Graphene oxide (GO), nanodiamonds (ND), and carbon nano-onions (CNO) displaying bismuth or tungsten oxide nanoparticles adhered to the surface and function as highly efficient photocatalysts for thiol-ene ligation under both UV and visible-light-mediated conditions. The straightforward catalyst preparation, excellent overall yields, ease of purification, and broad substrate scope render this a highly versatile method for bioconjugation.