2-salicylidine-4-aminophenyl benzimidazole (SAPbzlH, LH) has been synthesised and its complexes, formulated as ZnX 2 Ly.nH 2 O (X = Cl, y = 1.5, n = 1; X = Br, y = 2, n = 2; X = CH 3 COO, y = 1.5, n = 2), CdX 2 L.CH 3 OH.0.5H 2 O (X = Cl, Br) and HgX 2 L.nH 2 O (X = Cl, n = 2; X = Br, n = 0), have been characterised. A single crystal X-ray diffraction study of [Cd 2 Br 4 L 2 ].2CH 3 OH.H 2 O has revealed its binuclear structure with dibromide and SAPbzlH bridges, the environment around each metal ion being distorted trigonal bipyramidal. A similar structure is envisaged for the chloride analogue of cadmium as well as the mercury complexes.

The Schiff base, 2-salicylidene-4-aminophenyl benzimidazole in ethanol undergoes activation of -N=CH- bond by Ni(2+) in the presence of ammonia or primary alkyl amine to produce nickel complexes of the formula Ni{o-C(6)H(4)(O)CH NR}(2) . n H(2)O [R  =  H, Me; n  =  0; R  =  Et, n =  0.5] and 4-aminophenyl benzimidazole. The products have been identified by elemental analysis, magnetic susceptibility measurements and IR, ESR, mass and extensive NMR spectral studies. The possible mechanism for the activation of -N=CH- bond has also been proposed.

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