Ruthenium-catalyzed oxidation of a carbon–carbon triple bond: facile syntheses of alkenyl 1,2-diketones from alkynes

A new oxidation procedure of alkynes catalyzed by Tp(PPh3)(CH3CN)Ru–Cl is presented, which provides an efficient way to obtain alkenyl 1,2-diketones viaruthenium alkenyl 1,2-diketone intermediates. In contrast, the analogous reactions with Tp(PPh3)(PhCN)Ru–Cl gave rise to the ruthenium metallacycle complexes.