Palladium-catalyzed alkoxycarbonylation of terminal alkenes to produce α,β-unsaturated esters: the key role of acetonitrile as a ligand

A mild protocol has been developed for the Pd-catalyzed alkoxycarbonylation of terminal olefins to produce α,β-unsaturated esters with a wide range of substrates. Key features are the use of MeCN as solvent (and/or ligand) to control the reactivity of the intermediate Pd complexes and the combination of CO with O, which facilitates the Cu-mediated reoxidation of the Pd complex to Pd and prevents double carbonylation. Acetonitrile is the key! A mild protocol has been developed for the Pd-catalyzed alkoxycarbonylation of terminal olefins to produce α,β-unsaturated esters with a wide range of substrates (see scheme). Key features are the use of MeCN as a solvent (and/or ligand) to control the reactivity of the intermediate Pd complexes and the combination of CO with O, which facilitates the Cu-mediated reoxidation of Pd to Pd and prevents double carbonylation.