Oxygenation of phenylacetylene catalysed by Co(salen)[H2salen = 1,6-bis-(2-hydroxyphenyl)-2,5-diazahexa-1,5-diene]

Co(salen) catalysed oxygenation of 4-substituted phenylacetylenes in alcohols results in highly selective incorporation of oxygen into the triple bond to give the corresponding acetophenones, and mandelic and phenylglyoxylic esters.