Preparations and Properties of (3, 6, 9-Triazaundecanedioato)cobalt(III) Complexes with Unidentate Liga n ds (Cl, - Br-, NCS- or NH3)

In order to isolate new complexes of [Co(taud)a] (taud: -00CCH2NH(CH2)2NH(CH2)2NHCH, C00-), several preparative reactions were attempted by using the previous reported trans(O)-[Co(taud)(H2O)]ClO4 as the starting materials. Subsequently, it was foun d that four kinds of taud-Co(lll) complexes could be isolated as crystals with good yields. The elemental analyses indicated that the crystals had the compositions of [Co(taud)a]Xn H2O {(a=C1-; X=0; n=0.5), (a=Br-, NCS-; X=0; n=0), (a-=NH, ; X=C104-; n=0)}. On the basis of the absorption spectrum and the infrared spectrum for th e complex of [Co(taud)(NCS)], the donor atom of the NCS- ligand is the nitrogen atom N. From th e electronic spectral data and the preparative routes for the complexes obtained, therefore, it has been found that these all complexes have the trans(0) structure and the coordination modes of taud are trans(0).