Stereoselective preparation of (Z)-α-stannyl-1-alkenyl sulfoxides via hydrozirconation of acetylenic stannanes

Acetylenic stannanes (1) react with Cp2Zr(H)Cl (Cp=η5-C5H5) giving (Z)-α-stannylvinylzirconium complexes (2), which are trapped with sulfinyl chlorides (3) in THF at room temperature to afford (Z)-α-stannyl-1-alkenyl sulfoxides (4). The yields are 63–81%. The coupling of 4h with diphenyliodonium chloride in the presence of Pd(PPh3)4 and CuI afford (E)-α-phenyl unsaturated sulfoxide 5 in 75% yield.