Visible photons for the regioselective nucleophilic ring opening of epoxides

Abstract

Arylazo sulfones were used as Photoacid Generators (PAGs) for the visible-light photorelease of strong sulfonic acids to promote the ring opening of epoxides in benign media (DMC/water mixtures) or under neat conditions. Water, alcohols, azide and thiocyanate anions, as well as electron-rich aromatics were used in the role of the nucleophile. The resulting 1,2-disubstituted adducts were formed mostly in >99% yield in a high regioselective fashion.