
%0 Journal Article
%A Graham, PG 
%A Weatherburn, DC 
%T Dissociation kinetics of metal complexes in aqueous acid. III. The effects of methyl substitution and chelate ring size on the rates of dissociation of copper(II) triazamacrocyclic complexes
%J Australian Journal of Chemistry
%D 1984/11/01
%V 37
%N 11
%P 2243-2247
%K 
%R https://doi.org/10.1071/CH9842243
%U https://www.publish.csiro.au/paper/CH9842243 
%X The acid dissociation kinetics of mono copper(II) complexes of the ligands 2-methyl-1,4,7-triazacyclononane, mznn ; 1,4,7-triazacycloundecane, zaud ; 1,4,7-triazacyclododecane, zadd ; and 1,5,9-triazacyclotetradecane, zted were studied in aqueous solution over a range of acid concentra- tions (0.025-0.5 mol 1-1), I1.0 (NaN03). Cu(mznn)2+ displays a first-order dependence on [H+] with kH (298 K) 26 1. mol-1 s-1. The other complexes show an acid dependence at low [H+] but become independent of acid at higher concentrations. The acid-independent rate constants k1 were determined to be Cu(zaud)2+, 67 s-1 (280 K); Cu(zadd)2+, 45 s-1 (298 K); Cu(zted)2+ 50 s-1 (298 K). The results are compared with those obtained with other copper(II) triazamacro- cyclic complexes. 
