Bivalent transition metal complexes of 4,5-diazafluorene-9-one benzoylhydrazone (HL) and the characterization of weak interaction in CoL 2 (H 2 O) 2
作者:Wen Xiao、Zhong-Lin Lu、Cheng-Yong Su、Kai-Bei Yu、Liang-Rong Deng、Han-Qin Liu、Bei-Sheng Kang
DOI:10.1016/s0022-2860(00)00568-8
日期:2000.10
A new ligand 4,5-diazafluorene-9-one benzoylhydrazone (HL) and six of its transition metal complexes ML2. nH(2)O [M(II) = Mn, n = 2, 1; Co, 2, 2; Ni, 2, 3; Cu, 3, 4; Zn, 1.5, 5; Pb, 4, 6] have been prepared and characterized. Elemental analyses, IR, UV-Vis, H-1 NMR, molar conductivity and, thermal analyses measurements showed that the ligand coordinates to the metal ion with the enolic O and azomethine N atoms of the acylhydrazone group while the 4,5-diazafluorene moiety is free. Single crystal X-ray diffraction studies showed that CoL2(H2O)(2), 2, has a centrosymmetric octahedral geometry of N2O4 with the two bidentate ligands in the basal plane and the two water molecules in the axial sites. The molecules of 2 are linked together by intermolecular hydrogen bonds N-diazafluorene. . . HOH . . .N'(diazafluorene) and pi-pi stacking interactions between the diazafluorene rings to form 2D sheets. (C) 2000 Elsevier Science B.V. All rights reserved.