Asian Journal of Chemical Sciences

The ligand 1,3-bis-((5-methyl-1H-imidazol-4-yl)methyleneamino)propan-2-ol (H₃L) derived from 1,3-diaminopropan-2-ol and 5-methyl-1H-imidazole-4-carbaldehyde  has been synthetized and used to prepare five complexes in which the ligand acts in tetradentate fashion. Complexes formulated as [Mn(H₃L)(H₂O)₂].2SCN (1), [(Co(H₃L)].2SCN (2), [(Ni(H₃L)].2SCN (3), [(Cu(H₃L)(NO₃)].(NO₃).2H₂O (4), and [(Zn(H₃L)].2SCN (5) were synthesized by mixing an equimolar amount of an methanol solution containing the appropriate nitrate salt and KSCN, in 1:2 ratio, in the case of 1, 2, 3 and 5 and an ethanol solution containing the appropriate ligand H₃L. The complex 4 has been synthetized in the absence of KSCN. In all the complexes the ligand acts in its neutral form and in tetradentate fashion, its hydroxy group remaining free and non-deprotonated. The ligand is coordinated to metal ion through two azomethine nitrogen atoms and two pyrazole sp² nitrogen atoms. The complexes are characterized by elemental analysis, conductance and room temperature  magnetic moments measurements, UV–Vis and IR spectroscopic studies. The structure of the copper(II) complex 4 is confirmed by X-ray diffraction. 4 crystallizes in the monoclinic space group P2₁/c with unit cell dimensions a = 8.5459 (3) Å, b = 10.9177 (3) Å, c = 22.4562 (6) Å, b = 96.954 (3)°, V = 2079.79 (11) ų, Z = 4, R₁ = 0.050 and wR₂ = 0.131. The Cu^II cation in N₄O inner is situated in a distorted square pyramidal environment.