THE DEEP OXIDATION OF CHEMICAL WARFARE AGENT MODELS - FACILE CATALYTIC OXIDATIVE CLEAVAGE OF PHOSPHORUS-CARBON AND SULFUR-CARBON BONDS USING DIOXYGEN

In water, metallic palladium on carbon was found to catalyze the deep oxidation of organophosphorus and organosulfur compounds by dioxygen a t 90 degrees C in the presence of carbon monoxide. This system present s the first examples of catalytic cleavage of phosphorus-carbon bonds. Starting with trimethylphosphine oxide, the phosphorus-containing pro ducts formed by sequential P-C cleavage were dimethylphosphinic acid, methylphosphonic acid, and phosphoric acid. A similar reaction sequenc e was also observed for triethylphosphine oxide, except that products formed by partial oxidation of the ethyl groups, such as phosphonoacet ic acid, were also seen as intermediates. The deep oxidation of dimeth yl and diethyl sulfides proceeded through the intermediacy of the corr esponding sulfoxides. For the methyl derivatives, the ease of oxidatio n decreased in the order: (CH3)(2)S > (CH3)(2)SO > (CH3)(2)SO2 and is consistent with the system acting as an electrophilic oxidant.