Conformational analysis of EDTA-type chromium(III) complexes with beta-propionato metal chelate rings

摘要

Conformational analysis of the three geometrical isomers of (aqua)(ethylenediamine-tripropionato)cliromium(III) has been performed with the Consistent Force Field (CFF) program. Four stable conformations were identified for trans(H2O,O) and trans(H2O,N-H), and five stable conformations for trans(H2O,N') geometrical isomer. Their structure and relative strain were analyzed and compared with the available experimental data. The conformer representing the global minimum (population 58% at 298 K) was found to match closely the X-ray structure of the trans(H2O,N-H) isomer. The factors which determine the individual chelate ring conformations, and conformational transmission through the entire ligand system was elucidated, and a possible extension of this analysis to other EDTA-type complexes is indicated. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 23]