Crystal Structure of Mono- and Trinuclear Ni(II) Complexes with Bis-Azomethine Based on 2-Amino-3-Formylpyridine

Russian Journal of Coordination Chemistry - The structure of a new mononuclear nickel(II) complex with bis-azomethine [Ni(H2L)]+ · CH3COO– · H2O, resulting from condensation of...     

Synthesis,Structure, and Spectral Properties of 3,5-Di-tert-butyl-1,2-benzoquinone 3-Hydroxynaphthoyl Hydrazone and Its Complexes with Zn(II), Cd(II), Ni(II), and Co(II)

Russian Journal of General Chemistry - Novel complexes of Zn(II), Cd(II), Ni(II), and Co(II) with 3,5-di-tert-butyl-1,2-benzoquinone 3-hyd-roxynaphthoyl hydrazone have been synthesized....     

Protolytic properties of 8-quinolylhydrazones of substituted salicylaldehydes and physicochemical properties of their copper(II) complexes

Acid-base properties of hydrazones derived from 8-hydrazinoquinoline and substituted salicylaldehydes were studied. Under the experimental conditions, only the first step of ionization of the hydrazones is realized. The ionization constants were calculated quantum-chemically. Copper(II) complexes of these hydrazones, (HL)Cu(X)(CH₃OH)_n, were isolated (HL^? is the monodeprotonated form of hydrazones, and X^? is the acid residue). According to the data of elemental analysis, IR spectroscopy, conductometry, and magnetochemistry, the majority of the complexes have a binuclear structure. The copper(II) ions in the dimeric complex show antiferromagnetic exchange coupling. The ionization constants of the hydrazones and the exchange parameters strongly depend on the substituent in the salicylaldehyde moiety.     

2,6-Diformyl-4-<Emphasis Type="Italic">tert</Emphasis>-butylphenol bis(8-quinolylhydrazone) and its transition metal complexes: Physicochemical study and quantum-chemical simulation

2,6-Diformyl-4-tert-butylphenol bis(8-quinolylhydrazone) and its transition metal complexes of the compositions [Cu₂(H₂L)Cl]Cl₂, [Ni₂(H₂L)Cl₃], and [Mn₂(H₂L)Cl₃], where H₂L is the monodeprotonated form of the hydrazone, are prepared. The conformations of the bis-hydrazone, geometries of the complexes, and parameters of exchange coupling between the ferromagnetic centers are evaluated by quantum-chemical calculations. The calculation results are compared with the results of the physicochemical study of the compounds. Factors affecting the stability of various forms of the ligand and complexes are discussed.     

New Tridentate Schiff Base,Product of Condensation of 4-Methyl-7-hydroxy-8-formylcoumarin and <Emphasis Type="Italic">N</Emphasis>-Aminomercaptotriazole: Synthesis,Structure, and Complex Formation

A new Schiff base was prepared by the reaction of 4-methyl-7-hydroxy-8-formylcoumarin with N-aminomercaptotriazole. In solution and in solid phase the compound was shown to exist in the thione form. The compound reacts with Cu(II), Ni(II), Zn(II) and Cd(II) ions depending on the metal salt to give complexes of composition ML₂ or MHLX, where HL is monodeprotonated form of the ligand. Cu(II) and Ni(II) complexes were studied by spectral and magnetochemical methods. The Zn(II) and Cd(II) complexes exhibit fluorescence.     

Vibrational spectra of trinitromethane derivatives

Spectroscopic parameters of trinitromethane derivatives RC(NO₂)₃ (R = F, Cl, Br, I, NC, NF₂, N₃) were determined. Vibrational frequencies and modes were calculated and the assignment of experimental spectra was performed. Spectral features due to the mutual influence of the C(NO₂)₃ group and other atomic groups and particular atoms were revealed.     

Crystal structure of 2-acetylbenzimidazole 1′-phthalazinylhydrazone

Using X-ray diffraction study of acetylbenzimidazole 2-acetylbenzimidazole 1′-phthalazinylhydrazone we confirmed that this compounds exists as the phthalazonehydrazone tautomer, as was suggested earlier on the basis of IR and NMR spectroscopy and quantum-chemical calculations.