Construction of a new versatile hydrazonic ligand and its chemical and structural behaviour towards metal ions
摘要:
The synthesis of a new hydrazonic ligand, 2,6-diacetylpyridine bis[2-(semicarbazono)propionyl-hydrazone] (H4L), is reported together with the synthesis, X-ray structure analysis and the IR spectroscopic characterisation of the complexes [{Ni2(H2L)(OH2)Cl}2Cl2].2dmf.5H2O 1 (dmf = dimethyl-formamide), [Co(H4L)(OH2)2][NO3]2.2H2O 2 and [Zn(H3L')(OH2)2][ClO4]2.1.5H2O 3 [H3L' = 2,6-diacetylpyridine semicarbazone 2-(semicarbazono)propionylhydrazone]. The interest of these structures pertains mainly to the cations. In 1 a tetranuclear complex is present with two non-equivalent nickel atoms, both of which exhibit distorted-octahedral co-ordination, and with the hydrazone acting as enneadentate donor. The structures of 2 and 3 consist of monomeric units in which the metal atom has a pentagonal-bipyramidal environment with two axial H2O molecules and the hydrazone ligand forming the basal plane.
Construction of a new versatile hydrazonic ligand and its chemical and structural behaviour towards metal ions
摘要:
The synthesis of a new hydrazonic ligand, 2,6-diacetylpyridine bis[2-(semicarbazono)propionyl-hydrazone] (H4L), is reported together with the synthesis, X-ray structure analysis and the IR spectroscopic characterisation of the complexes [{Ni2(H2L)(OH2)Cl}2Cl2].2dmf.5H2O 1 (dmf = dimethyl-formamide), [Co(H4L)(OH2)2][NO3]2.2H2O 2 and [Zn(H3L')(OH2)2][ClO4]2.1.5H2O 3 [H3L' = 2,6-diacetylpyridine semicarbazone 2-(semicarbazono)propionylhydrazone]. The interest of these structures pertains mainly to the cations. In 1 a tetranuclear complex is present with two non-equivalent nickel atoms, both of which exhibit distorted-octahedral co-ordination, and with the hydrazone acting as enneadentate donor. The structures of 2 and 3 consist of monomeric units in which the metal atom has a pentagonal-bipyramidal environment with two axial H2O molecules and the hydrazone ligand forming the basal plane.