B. Singh et Ak. Srivastav, STUDIES ON SOME BIVALENT-METAL COMPLEXES OF SCHIFF-BASES, Synthesis and reactivity in inorganic and metal-organic chemistry, 24(9), 1994, pp. 1523-1536
2-Acetylfuran-2-furoylhydrazone (Haffh), 2-acetylthiophene-2-furoylhyd
razone (Hatfh), o-hydroxyacetophenone-2-furoylhydrazone (H2hafh) and 2
,6-diacetylpuridine bis(2-furoylhydrazone) (H2dapfh) react with zinc(I
I), cadmium(II) and mercury(II) chlorides and form the complexes of th
e types ML2Cl2 [M = Cd(II) and Hg(II), L = Haffh and Hatfh; M = Zn(II)
, Cd(II) and Hg(II), L = H2hafh], [MLCl]Cl [M = Cd(II) and Hg(II) and
L = H2dapfh] and Zn(Hhafh)2. The complexes M(H2acacfh)Cl2 [M = Cd(II)
and Hg(II), H2acacfh = acetylacetonebis(2-furoylhydrazone)] were prepa
red by template reaction. The complexes were characterized by elementa
l analyses and molar conductance. Infrared spectral studies reveal neu
tral bidentate bonding of Haffh, Hatfh and H2hafh in the complexes, ex
cept Zn(Hhafh)2, in which the Schiff base is bonded in an uninegative
tridentate fashion. H2dapfh is a neutral pentadentate ligand while H2a
cacfh is neutral tetradentate ligand. These observations are also supp
orted by H-1 and C-13 n.m.r. spectral studies. A six-coordinate geomet
ry around the metal ions has been proposed on the basis of these studi
es.