KINETICS OF THE CHROMIUM(II) REDUCTIONS OF CHELATED AMINO ACIDO-BIS(ETHYLENE-DIAMINE)COBALT(III) COMPLEXES

Abstract

The kinetics of Cr²⁺(aq) reductions of glycinato-, D,L-alanato, D,L-phenylalanato-, and D,L-leucinatobis-(ethylenediamine)cobalt(III) ions have been investigated. The rate law is of the form d(lnCo(III)]/dt = kCr²⁺], where the rate constant k(M^?1sec^?1) and associated activation parameters δH^δ(kcal mol^?1 and δS^δ (cal deg ^?1mol^?1) in parentheses, are respectively 1.65 · 0.06 (9.7 · 0.1, -25 · 1), 0.367 · 0.008 (10.9 · 04,-24 ·1), 0.529 · 0.021 (11.2 · 0.4, -22 · 1); and 0.358 · 0.019 (11.5 · 0.3, -22 · 1) at 298^·K and ·CIO·] = 1.0 M. The reactions are all inner-sphere.