Directed hydrozirconation of homopropargylic alcohols

Homopropargylic alcohols undergo directed hydrozirconation with Schwartz reagent (Cp2ZrHCl) to generate vinyl-metal species in which the metal fragment is proximal to the alkoxide. Electrophilic trapping yields tri-substituted olefins in good yields with good control of regio- and stereochemistry. Experiments with a homopropargylic ether confirmed the role of the hydroxyl group in the directed hydrometalation.