GENERAL-SYNTHESIS OF (Z)-ALK-1-EN-1-YL ESTERS VIA RUTHENIUM-CATALYZED ANTI-MARKOVNIKOV TRANS-ADDITION OF CARBOXYLIC-ACIDS TO TERMINAL ALKYNES

The direct addition of carboxylic acids to terminal alkynes in the presence of catalytic amounts of (bis(diphenylphosphino)alkane)Ru(eta(3)-methallyl)(2) complexes provides a novel selective route to (Z)-alk-1-en-1-yl esters. This reaction involves an anti-Markovnikov and trans-addition to alkynes and gives access to a variety of new (Z)-alkene derivatives from hex-1-yne, phenylacetylene, and (trimethylsilyl)acetylene. The actual catalyst precursors are (bis(diphenylphosphino)alkane)Ru(eta(2)-carboxylate)(2) complexes formed in situ during the reaction.