Ruthenium-Catalyzed Regioselective Hydrohalogenation of Alkynes Mediated by Trimethylsilyl Triflate.

Here we describe a ruthenium-catalyzed regioselective hydrohalogenation reaction of alkynes under mild conditions. Commercially simple halogen sources such as KI, ZnBr 2 , and ZnCl 2 were employed to achieve this transformation. Alkynes derived from bioactive molecules such as l-(-)-borneol, l-menthol, and estrone were also suitable for the transformation, demonstrating the potential synthetic value of this new reaction in organic synthesis.