TY - JOUR
T1 - Three new 1D Cu(II) coordination polymers and a binuclear Cu(II) complex of two pyrazole derived Schiff base ligands
T2 - Heterocyclic ring substitution and anion dependent structural variations - Spectral studies
AU - Konar, Saugata
AU - Jana, Atanu
AU - Das, Kinsuk
AU - Ray, Sangita
AU - Chatterjee, Sudipta
AU - Kar, Susanta Kumar
PY - 2013/1/30
Y1 - 2013/1/30
N2 - Three new zig-zag 1D coordination polymers and a binuclear complex of Cu(II) involving pyrazole based tri- and pentadentate schiff base ligands (Z)-2-(2-(5-methyl-1H-pyrazole-3-carbonyl)hydrazono)-2- phenylacetic acid (L'1) and (Z)-2-(2-(5-methyl-1-(pyridin-2-yl)-1H-pyrazole-3-carbonyl) hydrazono)-2- phenylacetic acid (L'2) are reported in this work. The ligand precursors L1 and L2 have been transformed into L1' and L2' during the course of reaction with metal ions in which the ester groups have been changed to carboxylate group. The 1D coordination polymers, namely, [Cu(L'1)(ClO4) 2(H2O)]n (1), [Cu(L'2)(- ClO 4)]n (3), [Cu(L'2)(NO3)]n (4) and a binuclear complex [Cu2(L'1)2Cl2] (2) have been synthesized. The complexes 1-3 are of distorted octahedral geometry and the complex 2 is distorted square pyramidal. Interestingly, these structural variations are dependent on counterions and substituent on the pyrazole ring. These have been characterized by elemental analyses, UV, IR, single crystal X-ray diffraction, electrochemical and photoluminescence studies. L'1 serves as tridentate NNO donor where pyrazole nitrogen, azomethine nitrogen and ligand carboxylate group are coordinatively active, leaving the carbonyl oxygen of carbohydrazide part inactive. The same situation (coordination modes) arises in another pentadentate NNNOO donor L'2 where extra pyridine nitrogen is coordinated. The complexes 3 and 4 have considerable fluorescence emission while the rest of the complexes and the ligand molecules are fluorescent silent.
AB - Three new zig-zag 1D coordination polymers and a binuclear complex of Cu(II) involving pyrazole based tri- and pentadentate schiff base ligands (Z)-2-(2-(5-methyl-1H-pyrazole-3-carbonyl)hydrazono)-2- phenylacetic acid (L'1) and (Z)-2-(2-(5-methyl-1-(pyridin-2-yl)-1H-pyrazole-3-carbonyl) hydrazono)-2- phenylacetic acid (L'2) are reported in this work. The ligand precursors L1 and L2 have been transformed into L1' and L2' during the course of reaction with metal ions in which the ester groups have been changed to carboxylate group. The 1D coordination polymers, namely, [Cu(L'1)(ClO4) 2(H2O)]n (1), [Cu(L'2)(- ClO 4)]n (3), [Cu(L'2)(NO3)]n (4) and a binuclear complex [Cu2(L'1)2Cl2] (2) have been synthesized. The complexes 1-3 are of distorted octahedral geometry and the complex 2 is distorted square pyramidal. Interestingly, these structural variations are dependent on counterions and substituent on the pyrazole ring. These have been characterized by elemental analyses, UV, IR, single crystal X-ray diffraction, electrochemical and photoluminescence studies. L'1 serves as tridentate NNO donor where pyrazole nitrogen, azomethine nitrogen and ligand carboxylate group are coordinatively active, leaving the carbonyl oxygen of carbohydrazide part inactive. The same situation (coordination modes) arises in another pentadentate NNNOO donor L'2 where extra pyridine nitrogen is coordinated. The complexes 3 and 4 have considerable fluorescence emission while the rest of the complexes and the ligand molecules are fluorescent silent.
KW - Copper(II) 1D coordination polymers
KW - Electrochemistry Spectral studies
KW - Pyrazole derived Schiff base ligands
KW - X-ray crystal structures
UR - http://www.scopus.com/inward/record.url?scp=84870830996&partnerID=8YFLogxK
U2 - 10.1016/j.ica.2012.10.013
DO - 10.1016/j.ica.2012.10.013
M3 - Article
AN - SCOPUS:84870830996
SN - 0020-1693
VL - 395
SP - 1
EP - 10
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
ER -