Catalytic, tunable, one-step bismuth(III) triflate reaction with alcohols: dehydration vs dimerization

Bi(OTf)3·xH2O is a powerful catalyst for the dehydration of tertiary alcohols into alkenes in apolar solvents. The reaction proceeds smoothly and selectively, with amounts as low as 0.01 mol % catalyst, in yields up to 93%. Moreover, in polar solvents, Bi(OTf)3·xH2O (0.1–1 mol %) selectively catalyzes the dimerization of the alcohols instead, forming new C–C bonds, in yields up to 96%. This mild, efficient, economic, and eco-friendly method is applicable across different chemical classes and amenable to several functional groups.