Palladium-catalyzed oxidative carbocyclization-carbonylation of allenynes and enallenes.

A highly efficient oxidative carbocyclization-carbonylation reaction cascade of allenynes and enallenes has been developed using a Pd(II) salt in low catalytic amounts under ambient temperature and pressure (1 atm of carbon monoxide). The use of DMSO as an additive was found to be important for an efficient reaction. A wide range of alcohols as trapping reagents were used to give the corresponding esters in good yields.