Bis(2,4‐dinitrophenyl) phosphate hydrolysis mediated by lanthanide ions

Abstract The kinetics of the hydrolysis of bis(2,4‐dinitrophenyl) phosphate (BDNPP) were studied in basic solutions in the presence of La 3+ , Sm 3+ , Tb 3+ and Er 3+ . Bis‐Tris propane (BTP) buffer was used to stabilize the Ln 3+ hydroxide complexes in solution. Two equivalents of the 2,4‐dinitrophenolate ion (DNP) were liberated for each equivalent of BDNPP and the reaction showed first‐order kinetics. Potentiometric titrations showed the formation of dinuclear complexes such as [Ln 2 (BTP) 2 (OH) n ] (6− n ) , with values of n varying as a function of pH, for all studied metals. Hence the catalytic effect depends on the formation of dinuclear lanthanide ion complexes with several hydroxo ligands. Copyright © 2004 John Wiley & Sons, Ltd.