Collect. Czech. Chem. Commun. 1989, 54, 3220-3229

The crystal and molecular structure of configurationally chiral unsym-fac-[N-(2-aminoethyl)-1,3-diaminopropane-(S)-aspartato]cobalt(III) perchlorate with dominating vicinal effect in its circular dichroism

Jan Ondráčeka, Jaroslav Maixnera, Bohumil Kratochvíla, Jana Ondráčkováb and František Jursíkb

a Department of Solid State Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6
b Department of Inorganic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6


The crystal and molecular structure of unsym1-fac-Λ-(δ, chair)-(S)-[Co(aepn)(S)-Asp]ClO4(trans-6,6) was solved by the heavy atom method. The positions of the non-hydrogen atoms and their anisotropic temperature parameters were refined on the basis of 1 935 observed reflections, yielding values of R = 0.121 and wR = 0.117, affected by the undertermined position of the oxygen atoms in the ClO4-> anion. The substance crystallizes in the orthorhombic system with space group P212121; Z = 4, a = 9.664(1), b = 11.805(1), c = 13.966(2) Å. The secondary atom of the triamine has S configuration, the conformation of the five-membered chelate ring approaches that of the asymmetrical δ envelope and the six-membered ring has chair configuration. Both conformations are deformed. The donor atoms deviate from the defined planes and thus form further sources of chirality (λ) contributing to the optical activity of the isomer. These deviations lead to the similarity of the CD spectra of the isomers.