HYDROCARBON AND PHOSPHATE TRIESTER FORMATION DURING HOMOLYTIC HYDROLYSIS OF ORGANOPHOSPHONIUM IONS - AN ALTERNATE MODEL FOR ORGANOPHOSPHONATE BIODEGRADATION

Treatment of organotrineopentoxyphosphonium trifluoromethanesulfonates with base and organic peroxides results in carbon to phosphorus (C-P) bond cleavage. The products of the homolytic hydrolysis are hydrocarbons and trineopentyl phosphate. Reaction of the organophosphonium ions with only base leads to oxygen to phosphorus (O-P) bond cleavage with a complete absence of C-P bond cleavage. The likely intermediacy of a pentacovalent phosphonyl radical during the homolytic hydrolysis provides the basis for an alternate mechanistic formulation for the C-P bond cleavage observed during organophosphonate biodegradation. This formulation is unique in its prediction of inorganic phosphate as the immediate phosphorus-containing product of microbe-mediated C-P bond cleavage.