Ligand environment and the structure of schiff base adducts and tetracoordinated metal-chelates

N,N'-ethylenebis(salicylideneiminato) transition metal ion chelates

Synthesis and characterisation of tin(IV) and organotin(IV) derivatives 2-{[(2-hydroxyphenyl)imino]methyl}phenol

Three ligands have been formed by the 1:2 molar condensation of o-phenylenediamine with salicyldhyde, 2-hydroxy-1-naphthaldhyde or o-hydroxyacetophenone. The potentially tetradentate ligands are N,N′-bis(salicyldhyde)-o-phenylenediamine(SalophH2), N,N′-bis(2-hydroxy-1-naphthaldhyde)-o-phenylenediamine (NophH2) and N,N′-bis(o-hydroxyacetophenone)-o-phenylenediamine (AophH2), respectively. These ligands form complexes (1:1 molar ratio) with nickel, copper and zinc ions. The complexes have been characterized by IR, 1HNMR, MS, uv/vis spectra in addition to elemental analysis. The spectral data of the ligands and their complexes with nickel, copper and zinc are discussed in connection with the structural changes which occur due to complexation.

Spectroscopic Characterization of Some Tetradentate Schiff Bases and Their Complexes with Nickel, Copper and Zinc

Adduct formation between M(ClO4)2 and nickel(II) complexes of tetradentate Schiff-base ligands ([NiL]) have been investigated in acetonitrile by means of UV−vis spectrophotometric analysis (M2+= Mg2+, Ca2+, Sr2+, Ba2+, Ni2+; [NiL] = [Ni(salen)] = [N,N‘-ethylenebis(salicylideneiminato)]nickel(II), [Ni(salphen)] = [N,N‘-o-phenylenebis(salicylideneiminato)]nickel(II), [Ni(salpren)] = [N,N‘-propylenebis(salicylideneiminato)]nickel(II)). [NiL] complexes act as bidentate oxygen-donor ligands forming adducts of the type [(NiL)M]2+ and [(NiL)2M]2+ whose general order of increasing stability was correlated to the dimensions of the M2+ cations. Complexes of general composition 2[Ni(salen)]·M(ClO4)2 were isolated as powders in the solid state (M = Sr, Ca, Mg). X-ray structures of the crystalline complexes [{Ni(salen)}2Ba(ClO4)2(thf)] (1) (thf = tetrahydrofuran) and [{Ni(salen)}2Ni(H2O)2](ClO4)2 (2) are reported. 1 crystallizes in the space group P21/c (a = 10.995 A; b = 20.830 A; c = 19.567 A, β = 116.94°) and 2 in ...

V.H. Kulkarni

Papers

A spectroscopic study of tin(IV) complexes with bidentate Schiff bases

A spectroscopic study of tin(IV) complexes with multidentate Schiff bases

Titanium(IV) complexes with aromatic schiff bases

Complexes of lead(IV) with schiff bases