Synthesis, spectroscopy, and magnetic properties of FeII and CoII quinoline-2-carboxylates -: Crystal structure of trans-bis(quinoline-2-carboxylato)bis(propanol)iron(II)

The new coordination compounds, [Fe(qum-2-c)(2)(EtOH)(2)] (1), [Co(quin-2-c)(2)(EtOH)(2)] (2), and [Fe(quin-2-c)2(PrOH)(2)] (3) (where quin-2-c = quinoline-2-carboxylate) have been synthesized and investigated by ligand field, IR, Raman, and Mossbauer spectroscopy and by magnetic measurements. The X-ray analysis of the structure of 3 has been performed and refined to an R factor of 0.0377. The compound crystallizes in the monoclinic space group P2(1)/n with a = 6.104(1), b = 10.515(2), c = 19.339(4) Angstrom, beta = 92.57(3)degrees. The trans N2O4 environment around the Fen ion has a distorted octahedral geometry and the quin-2-c ion coordinates to iron in the equatorial plane in a chelating mode. The axial positions are occupied by propan-1-ol molecules. The spectral studies indicate the same molecular structure for all three compounds. The magnetic susceptibility and the magnetization of 2 were calculated for CO2+ ions in an octahedral crystal field with a rhombic zero field distortion (\D\ = 34 cm(-1), E approximate to 0, g(iso) = 2.35 and N = 6.9(.)10(-4) emu(.)mol(-1)). (C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.