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Hydrazones derived from substituted benzoyl hydrazides and benzil a-monoxime [viz. benzil a-monoxime benzoylhydrazone (BMBH), benzil a-monoxime 4-chlorobenzoylhydrazone (BMPCBH), benzil a-monoxime 4-methoxybenzoylhydrazone (BMMBH), benzil a-monoxime 4-nitrobenzoylhydrazone (BMNBH) and benzil a-monoxime 2-chlorobenzoylhydrazone (BMOCBH)] have been synthesized and used in preparing the corresponding Cr(III), Mn(III), Fe(III) and Co(III) complexes. The ligands undergo deprotonation in ethanolic alkaline solution to form dinuclear complexes. The complexes are insoluble in common organic solvents, decompose above 300°C, and are spin-free octahedral. The complexes isolated were characterized by elemental analyses, IR, electronic, 1 H NMR spectra, conductance, thermal studies and magnetic susceptibility measurements. The bonding and probable structures of the complexes are discussed on the basis of the spectral and magnetic data. The ligands, as well as their complexes, show antifungal activity. [ABSTRACT FROM AUTHOR]

A novel mesogenic Schiff base, N-(4-butylphenyl) salicylaldimine (Hbpsal), was prepared and its ligational behavior towards some 3 d metal ions studied. All the metal complexes synthesized were of the general formula, [M(bpsal) 2 (H 2 O) 2 ] where M=Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). The complexes were structurally characterized by elemental analyses, molar conductance, IR, NMR, and electronic spectral data. The metallo mesogenic phases of the Cu(II) complex were studied by optical microscope. The spectral data show that Hbpsal acts as a bidentate ligand towards the metal ions. Mesogenic studies indicate that the ligand shows a focalconic structure with smectic-A phase while the Cu(II) complex displays smectic-A as well as smectic-E phases. [ABSTRACT FROM AUTHOR]

The complexes[M(L)(H2O)x]n[M = Co(II), Ni(II), Cu(II), Zn(II), Cd(II)] and[M2(L)3]n[M = Mn(III), Fe(III)] and[VO(HL)2] with N-picolinoyl-N′-2-furanthiocarbohydrazide(H2L) have been prepared and characterized by elemental analyses, magnetic susceptibility measurement, electronic, NMR(1H and 13C), IR and FAB mass spectral data. Physico-chemical studies indicate that the complexes are polymeric in nature. The room temperature ESR spectra of[VO(HL)2] and[Cu(L)]n complexes yield〈g〉 values, characteristic of square-pyramidal and square-planar complexes, respectively. The Mössbauer spectra of[Fe2(L)3]n at room temperature and at 78 K suggest the presence of high-spin(S = 5/2) and low-spin(S = 1/2) forms of Fe(III) in the same complex at both temperatures. The complexes of OV(IV), Fe(III), Ni(II), and Cd(II) show semiconducting behaviour in the solid state in the temperature range 307–397 K, with a band gap of 0.18–0.44 eV. The other complexes are insulators. [ABSTRACT FROM AUTHOR]