Mechanism of reaction of palladium(II) carboxylates with carbon monoxide in nonaqueous media

The reduction of Pd II carboxylates by carbon monoxide in benzene and AcOH solutions has been studied. In the case of Pd II acetate the reaction is found to proceed through an intermediate complex with a Pd-CO-CH 3 group and the Pd I carbonylacetate [Pd(CO)(OAc)] 4 (PCA). A reductive condensation type of mechanism is suggested for the PCA decomposition on the base of kinetic data. The metal cluster skeleton is proposed to increase stepwise as the oxidation state of Pd decreases. A number of Pd I complexes, PCA analogs having composition [Pd(CO)(OCOR)] 4 , where R = C 2 H 5 , C 6 H 5 , CF 3 , CCl 3 , CH 2 Cl, have been prepared.