Regio- and Stereoselective Synthesis of Z-Vinylic Tellurides from Propargylic Alcohols: A Route to Chiral Z-Enynes

tert -Butyldimethylsilyl ethers of propargylic alcohols are hydrotellurated regioselectively to give 1,2- Z -vinylic tellurides. Enantiomerically pure propargylic alcohols give enantiomerically pure vinylic tellurides, which are coupled with alkynes under Pd catalysis to give enantiomerically pure allylic enynols.