Nickel-promoted alkylative or arylative carboxylation of alkynes

[GRAPHICS] Nickel-promoted alkylative or arylative carboxylation of terminal alkynes via a carbon dioxide fixation process was investigated. In the presence of a stoichiometric amount of a zero-valent nickel complex, the reaction of alkynes with CO2 gave a nickelacycle, which was reacted with various organozinc reagents under very mild conditions to provide beta,beta'-disubstituted, alpha,beta -unsaturated carboxylic acids in a highly regio- and stereoselective manner.