Ruthenium-catalyzed oxidative cleavage of alkynes to carboxylic acids

We describe an efficient method for the oxidative cleavage of alkynes to carboxylic acids using a combination of RuO2/Oxone/NaHCO3 in a CH3CN/H2O/EtOAc solvent system. Both internal and terminal alkynes, regardless of their electron density, can be oxidized to carboxylic acids in excellent yield (up to 99%). H-1 NMR spectroscopy and ESIMS experiments provided evidence for alpha-diketones and anhydrides as possible intermediates in these oxidation reactions.