SYNTHESIS AND CHARACTERIZATION OF SPIN-FREE '-TETRA(4-ANTIPYRYLMETHYL)-1,2-DIAMINOETHANE)CL-4]

The ligand N,N'-tetra(4-antipyrylmethyl)-1,2-diaminoethane (TAMEN) coo rdinates to two Co(II) ions and forms the tetrahedral homodinuclear co mplex [Co-2(TAMEN)Cl-4]. In methanol, the complex shows a weak absorbt ion spectrum with a maximum at 515 +/- 0.5 nm and a molar absorbtivity of 40.0 +/- 1.0 1.mol(-1).cm(-1). Variable temperature spectra (282 t o 323 K) show no changes of this band and suggest the absence of therm ochromicity. The magnetic moments amount to 4.93 to 5.00 mu(B) at the temperature range of 232 to 329 K, demonstrating the complex to be spi n-free in methanol.