PREPARATION AND CHARACTERIZATION OF CO(III)-DIMETHYLDITHIOCARBAMATO COMPLEXES CONTAINING 1,2-BIS(DIMETHOXYPHOSPHINO)ETHANE - MOLECULAR-STRUCTURES OF [CO((CH3)2NC(S)S)(R2P(CH2)2PR2)2](BF4)2 (R=CH3O AND CH3)

The [Co(dtc)3-n(dmope)n]n+ (n=1, 2) complexes were prepared, where dtc and dmope denote a dimethyldithiocarbamate ion and 1,2-bis(dimethoxyphosphino)ethane, respectively. The absorption and magnetic circular dichroism (MCD) spectra, and reduction and oxidation potentials were compared with those of the corresponding 1,2-bis(dimethylphosphino)ethane (dmpe) and related complexes. The molecular structures of [Co(dtc)-(dmope)2](BF4)2 (1) and [Co(dtc)(dmpe)2](BF4)2 (2) were determined by the X-ray diffraction method. Crystal data are; for 1, monoclinic, Cc, a=18.154(5), b=12.533(2), c=14.447(3) angstrom, beta=101.69(2)-degrees, V=3219(1) angstrom3, D(x)=1.61, D(m)= 1.60(3) g cm-3, and Z=4, R=0.044 for 3259 reflections; for 2, monoclinic, P2(1)/a, a=1 8.967(3), b=10.333(1), c=14.459(2) angstrom, beta=90.10(2)-degrees, V=2833.8(7) angstrom3, D(x)=1.53, D(m)=1.54(4) g cm-3, Z=4, R=0.052 for 5662 reflections. The average Co-P bond distance trans to S is 2.186(2) angstrom for 1 and 2.240(1) angstrom for 2, and that trans to P is 2.226(2) angstrom for 1 and 2.278(1) angstrom for 2. The Co-P distances in 1 are shorter by ca. 0.05 angstrom than those in 2, while the average Co-S bond distances are similar, 2.288(1) angstrom for 1 and 2.282(3) angstrom for 2.