The equilibrium kinetics in aqueous solutions of the chromium(II)-ethylenediamine (en) and -iminodiacetate (ida) complexes has been studied using a n.m.r. relaxation method. The paramagnetic relaxation rate and shift of the CH2 protons of the ligands were measured over a wide range of the complex formation. The formation rate constants (dm3 mol-1 s-1) of the mono and bis complexes were determined: k1en = 6.0 × 109, k2en = 3.2 × 108, k1ida = 4.9 × 109, k2ida = 2.4 × 107. Kinetic evidence is given for the formation of [Cr(Hida)]+ and [Cr(ida)3]4- complexes. The complex-formation kinetics of some complexes of Cr2+ and Cu2+ is compared; the similarities and differences are discussed.
|Number of pages||4|
|Journal||Journal of the Chemical Society, Dalton Transactions|
|Publication status||Published - Dec 1 1990|
ASJC Scopus subject areas