Aryl-substituted epoxides undergo smooth rearrangement in the presence of 0.01–0.1 mol% Bi(OTf)3•xH2O. The rearrangement is regioselective with aryl-substituted epoxides, and products arise from cleavage of the benzylic C―O bond. The highly catalytic nature of this method coupled with the fact that the reagent is relatively non-toxic, easy to handle and inexpensive make it an attractive alternative to more corrosive and toxic Lewis acids, such as BF3•Et2O, currently used to effect epoxide rearrangements.
Mohan, Ram; Bhatia, Kaushik; Eash, Kyle; Leonard, Nicholas; and Oswald, Matthew, "A Facile and Efficient Method for the Rearrangement of Aryl-substituted Epoxides to Aldehydes and Ketones using Bismuth Triflate" (2001). Scholarship. 21.