The exclusive formation of cyclopentenones from molybdenum hexacarbonyl-catalyzed Pauson-Khand reactions of 5-allenyl-1-ynes

The exclusive formation of cyclopentenones was observed in molybdenum hexacarbonyl catalyzed Pauson-Khand reactions of 1,6-allenynes under 1 atm of CO (balloon) in excellent yields.