A rare pentanuclear cadmium(II) complex and two new mononuclear zinc(II) complexes of pyrazole derived ditopic ligands – Synthesis, crystal structures and spectral studies

摘要: Abstract Pyrazole based ditopic ligand HL1 ((Z)-N′-(5-methyl-1H-pyrazole-3-carbonyl) picolinohydrazonamide) reacts with Cd(ClO4)2·6H2O and Zn(ClO4)2·6H2O to form a self assembled pentanuclear Cd(II) complex [Cd5(L1)6](ClO4)4 (1) mononuclear Zn(II) [Zn(HL1)2](ClO4)2 (2). On the other hand, HL2 pyrazine-2-carbohydrazonamide) also forms [Zn(HL2)](ClO4)2(MeOH)2 (3) Zn(ClO4)2.6H2O. All these complexes have been characterized crystallographically spectroscopically. The has core trigonal bipyramidal arrangement of atoms, where, axial metal centers (Cd2 Cd5) N3O3 chromophore equatorial (Cd1, Cd3 Cd4) N4O2 distorted octahedral around centres. In 2 3, NNO donor molecules in their ketoimine produce environment centre utilizing pyridine/pyrazine N, one azomethine N carbohydrazide O atoms. Here, pyrazole ring atoms remain silent coordination process. 1, same coordinates its deprotonated imineol functions as N3O donor, while, take part Ligands are fluorescence but 3 show considerable fluorescence. intensity 1 is higher than that 3.