
%0 Journal Article
%A Fayyaz, MU 
%A Grant, MW 
%T The Lewis-acidity of square-planar nickel(II) complexes. III. A kinetic study of the effects of substituents on the addition of 1,10-Phenanthroline to Bis(monothioacetylacetonato)nickel(II) and Bis(dithiophosphato)nickel(II) complexes in toluene
%J Australian Journal of Chemistry
%D 1978/07/01
%V 31
%N 7
%P 1439-1447
%K 
%R https://doi.org/10.1071/CH9781439
%U https://www.publish.csiro.au/paper/CH9781439 
%X The second-order rate constants and activation parameters for the addition of 1,10-phenanthroline to bis(dialkyldithiophosphato)nickel(II) complexes and substituted bis(monothioacetylacetonato)-nickel(II) complexes in toluene have been measured. Rate constants are in the range 102-108 1. mol-1 s-1 at 25&#176;C, while &#916;H&#8225; is in the range 10-50 kJ mol-1 and &#916;S&#8225; is in the range from -30 to -110 J mol-1 K-1. The higher rate constants, smaller &#916;H&#8225; and more negative &#916;S&#8225; values are associated with complexes with electron- withdrawing substituents. The results are related to the thermo- dynamics of adduct formation, the inductive effects of the substituents and the pKa of the ligands. 
