Synthesis, structural and luminescence studies of some zinc complexes having pyrazole and carboxylate ligands
摘要:
Some zinc (II) complexes having formula [Zn(Pz(iPr2)H)(mu-Pz(iPr2))(RCOO)](2) [(Pz(iPr2)H = 3,5-diisopropylpyrazole, RCOO = carboxylate ligands with R is CH3 for 1, CF3 for 2, CH3(CH2)(2) for 3, CH3(CH2)(4) for 4 and CH3(CH2)(5) for 5] were prepared and structurally characterized by different techniques including single crystal X-ray. The X-ray studies suggested that all these complexes are centrosymmetric dinuclear with tetrahedral geometry around each zinc center. The pyrazole ligand is coordinated in both terminal as well as a bridging fashion whereas the carboxylates behave as monodentate ligand. All the complexes show hydrogen bonding between hydrogen atom of pyrazole (N-H of terminal pyrazole) and nonbonded oxygen atom of carboxylate. Out of these complexes only 5 [Zn(Pz(iPr2)H)(mu-Pz(iPr2))(CH3(CH2)(5)COO)](2) exhibited emission at room temperature. (C) 2009 Elsevier B.V. All rights reserved.