Formation and hydrolysis of a diaqua(ethane-1,2-diamine)palladium(II) complex of ethyl glycinate

Abstract

The reaction of [Pd(en)(OH₂)₂]²⁺(en = ethane-1,2-diamine) with ethyl glycinate has been studied by potentiometric titrations. Reaction in solution is given by equilibrium (i), where L = H₂NCH₂CO₂C₂H₅; [Pd(en)(OH₂)₂]²⁺+ L [graphic omitted] [Pd(en)L]²⁺+ 2 H₂O (i) log K₁= 7.12 ± 0.03 at 25 °C and 0.5 mol dm^–3 KNO₃. The rate of hydrolysis of [Pd(en)L]²⁺ was studied on a pH-stat. Equations (ii) and (iii) account for the kinetic data. The rate constants k₁ and k′₂[Pd(en)L]²⁺+ OH^– [graphic omitted] product (ii), [Pd(en)L]²⁺+ H₂O [graphic omitted] product (iii) are 1.06 × 10⁴ dm³ mol^–1 and 2.10 × 10^–4 s^–1 respectively at 25 °C and 0.5 mol dm^–3 KNO₃, where k′₂=k₂[H₂O].