A Comparison between Kinetic Parameters from the Synthesis of Tris(p-nitrophenyl)phosphite and Tris(p-nitrophenyl)phosphate Using Reaction Calorimetry

Tris(p-nitrophenyl)phosphite was prepared by a modification of a "one-pot" methodology developed for the preparation of triaryl phosphates. This exothermic reaction was performed in a Mettler RC-1 calorimeter. The principal aim of this work was to compare the reactivity of phosphorus trichloride and phosphorus oxychloride in their reactions with sodium p-nitrophenoxide. The reaction rate and the reaction rate constant for the synthesis of tris(p-nitrophenyl)phosphite were evaluated and compared to the obtained values for the tris(p-nitrophenyl)phosphate synthesis. Phosphorus trichloride was found to react faster than phosphorus oxychloride, but the reaction with the phosphorus oxychloride proved to be more exothermic.