Preparation of the partially substituted (phenoxy)chlorocyclotriphosphazenes by phase-transfer catalysis

In this study, phase-transfer catalysis was carried out for the substitution reaction of hexachloro-cyclotriphosphazene, N3P3Cl6 (I), by phenol to synthesize the partially substituted (phenoxy)chlorocyclotriphosphazenes, N3P3Cl6-x(OC6H5)x, x = 1-5. The kinetics of the reaction with the molar ratio of phenol and I equal to 2 was studied as a model reaction. It showed that the model reaction was mainly mass-transfer controlled and was second order with respect to the phenoxide. The optimum conditions were found for producing each derivative of the partially substituted (phenoxy)chlorocyclotriphosphazenes, N3P3Cl6-x(OC6H5)x, x = 1-5, such that the derivative predominates with high yield (over 75% of theory) in the mixture of the products. It was found that phase-transfer catalysis is a much more convenient and economic method than the conventional method for synthesizing partially substituted (phenoxy)chlorocyclotriphosphazenes.