Register      Login
Australian Journal of Chemistry Australian Journal of Chemistry Society
An international journal for chemical science
RESEARCH ARTICLE

Thermodynamics of Metal-Ligand Bond Formation. XVIII Addition of Heterocyclic Bases to Copper(II) and Cobalt(II) Schiff Base Complexes

L Ang and DP Graddon

Australian Journal of Chemistry 29(3) 565 - 571
Published: 1976

Abstract

Thermodynamic data are reported for reaction of heterocyclic bases in benzene solution with four-coordinate copper(11) and cobalt(11) Schiff base complexes and also with a five-coordinate nickel(11) complex. The cogper(11) complexes form adducts of low stability with pyridine or 4-methylpyridine, K ≈ 21. mol-1, ΔHº ≈ -20 kJmol-l. The cobalt(11) complexes add two molar proportions of base successively 1 < K1 ≤ K2 < 101.mol-1 ΔH1º ≈ ΔH2º ≈ -20 kJ mol-1 They also form adducts with 2,2'-bipyridine 30 < K < 600 ΔHº ≈ -40kJ mol-1 The nickel(11) complex forms more stable adducts with unidentate bases, K ≈ 1001. mol-l, ΔHº ≈ 70 kJ mol-1. Comparison of the three metals indicates that differences between the stabilities of their base adducts can be attributed mainly to entropy factors.

https://doi.org/10.1071/CH9760565

© CSIRO 1976

Committee on Publication Ethics


Export Citation Get Permission

View Dimensions