CRYSTAL-STRUCTURES AND ABSOLUTE-CONFIGURATIONS OF (+)589-LI[CO(EDTP)].3H2O AND (+)589-LI[CR(EDTP)].3H2O COMPLEXES OF ETHYLENEDIAMINE-N,N,N',N'-TETRA-3-PROPIONATE ION AND CORRELATIONS WITH CIRCULAR-DICHROISM SPECTRA

The complexes, (+)589-Li[M(edtp)].3H2O (M = Co or Cr; edtp = ethylenediamine-N,N,N',N'-tetra-3-propionate ion) crystallize in the space group P2(1) of the monoclinic crystal system with Z = 2. For M = Co, a = 8.824(2), b = 11.910(3), c = 8.7282(2) angstrom, beta = 95.03(1)-degrees and for M = Cr, a = 8.705(1), b = 11.940(2), c = 9.033(1) angstrom, beta = 94.19(1)-degrees. The absolute configuration is DELTA(lambda-lambda) for each complex where lambda-designates the conformation of the axial beta-alaninate rings. Significant sources of strain are found and discussed for both complexes. The distortion from octahedral coordination in these [M(edtp)]-complexes is greater for Co(III) than it is for Cr(III) which is unusual compared to other [M(edta)]--type complexes. The absolute configurations of the complexes are consistent with earlier reports of their circular dichroism spectra.