Chain polymeric complexes of some first-series transition-metal ions with N,N,N′,N′-tetra-acetyl-1,4-diaminobutane

The preparations are reported of the compounds [M(TADB)(H2O)2](ClO4)2 (where TADB=N,N,N′,N′-tetra-acetyl-1,4-diaminobutane, and M=Mn, Co, Ni and Zn), and also of the analogous tetrafluoroborate salts with M=Mn, Co, Cu and Zn, and the complex Cu(TADB)(ClO4)2. Crystals of [Zn(TADB)(H2O)2](ClO4)2 are monoclinic, P21/n, with a=7.3735(2), b=12.4954(5), c=12.0313(5) Å, β=100.581(4)°, and Z=2. Each zinc centre is coordinated to two trans-disposed aqua ligands and two chelating diacetamide units, one from each of two different TADB ligands, which, in turn bridge neighbouring zinc centres so as to generate cationic polymeric chains. X-ray powder diffraction studies show that, except for the copper(II) compounds, the other complexes are isostructural with the zinc complex. X-band EPR spectral results for the manganese(II) complexes and for samples of the other compounds ‘doped’ with small amounts of manganese(II) are also given.