
%0 Journal Article
%A Hambley, TW 
%A Searle, GH 
%A Snow, MR 
%T The structure of mer-bis[di(3-aminopropyl)amine]cobalt(III) perchlorate, and an energy minimization analysis of the [Co(dpt)<sub>2</sub>]<sup>3+</sup> system
%J Australian Journal of Chemistry
%D 1982/07/01
%V 35
%N 7
%P 1285-1295
%K 
%R https://doi.org/10.1071/CH9821285
%U https://www.publish.csiro.au/paper/CH9821285 
%X X-ray crystallographic analysis shows that the isolated [Co(dpt)2](ClO4)3 [dpt = di(3-aminopropyl)-amine] is the mer geometric isomer. All four six-membered chelate rings of the complex adopt flattened chair conformations, and substantial internal strain is evident in the structure. The crystals are monoclinic, space group P21/c, with a 15.259(3), b 10.646(2), c 15.367(3) Å, &#946; 9935(1)º. The structure was refined by blocked-matrix least-squares techniques to an R factor (on 1731 F) of 0.042. A molecular mechanics study of the [Co(dpt)2]3+ system shows that the structure (geometric isomer and conformer) having the lowest strain energy is mer-(chair, chair, chair, chair) which is that observed in the solid state, and predicts its coexistence in solution with several other conformers, particularly mer-(chair, chair, chair, &#955;-skew) and mer-(chair, chair, &#948;skew, chair). The calculated isomer proportions are mer » u-fac > s-fac in accordance with the experimental observation of the mer only. The substantially higher strain energy of the mer isomer compared to mer-[Co(dien)2]3+ accounts for the tendency to hydrolysis of mer-[Co(dpt)2]3+. 
