
%0 Journal Article
%A Dwyer, M 
%A Searle, GH 
%T Stereochemistry in the Bis(1,4,7-triazacyclodecane)cobalt(III) system and force field calculations
%J Australian Journal of Chemistry
%D 1981/10/01
%V 34
%N 10
%P 2025-2033
%K 
%R https://doi.org/10.1071/CH9812025
%U https://www.publish.csiro.au/paper/CH9812025 
%X An analysis of the stereochemical possibilities for the [Co(tacd)2]3+ complex is presented (tacd = 1,4,7-triazacyclodecane). Stereochemical variables are cis (chiral) and trans relative dispositions of the two six-membered rings, combinations of alternative conformations for the six chelate rings in the complex, and alternative configurations R or S about one secondary amine nitrogen in each coordinated ligand. Energy minimization calculations have been carried out on a number of the possible isomers, from which it is deduced that the most stable conformational arrangements in the trans geometry are {&#955;&#948; chair,A 6 chair} and {I. 6 chair,6 6 chair), and those in the cis geometry are { &#955;&#948; chair &#948;&#948; chair}, { &#955;&#948; chair &#948;&#948; chair } and { &#955;&#948; chair &#948;&#948; chair skew). The calculations give the trans-cis energy difference as 9.3 kJ mol-1, to be compared with the experimental free energy difference of 8 ± 1 kJ mol-1. 
