Nickel(0)-mediated sequential addition of carbon dioxide and aryl aldehydes into terminal allenes

[GRAPHICS] Nickel-mediated sequential addition of carbon dioxide and aryl aldehydes into terminal allenes; is reported. The reaction proceeded in a diastereoselective manner to afford alpha-methylene-gamma-hydroxy carboxylic acids, which allowed stereoselective preparation of cis-beta,gamma-disubstituted alpha-methylene-gamma-lactones.