Magnesium-Catalyzed Stereoselective Hydrostannylation of Internal and Terminal Alkynes.

A regio- and stereoselective magnesium-catalyzed hydrostannylation of internal and terminal alkynes has been developed. Excellent yields and selectivities are obtained for a wide range of terminal and internal symmetrical and unsymmetrical alkynes by using this alkaline earth metal catalyst as an effective alternative to transition metal catalysts.