Asian Journal of Chemistry; Vol. 25, No. 8 (2013), 4323-4326
Physico-chemical Investigation of Th(IV) and UO2(VI) Complexes of Schiff Bases
1
2,*
SONAL AGNIHOTRI and KISHOR ARORA
1Department of Chemistry, K.R.G. P.G. College, Gwalior-474 001, India
2Department of Chemistry, Government College, Datia-475 661, India
*Corresponding author: E-mail: kishorarora@rediffmail.com
(Received: 25 April 2012;
Accepted: 9 February 2013)
AJC-12955
Schiff bases were obtained using p-methoxy benzaldehyde and p-chloro benzaldehyde and 2-amino pyridine to prepare new complexes of
thorium(IV) and dioxouranium(VI) metals by various anions. The synthesized ligands and complexes were analytically studied through
spectral studies, elemental analysis conductance measurements along with semi empirical and thermogravimetric methods. The com-
plexes were assigned various coordination numbers ranging from 6-10 on the basis of these studies.
Key Words: Synthesis, Analytical studies, Thorium(IV) and dioxouranium complexes, Schiff base, Coordination number.
IR spectra were taken through Schimadzu 8201 PC (4000-
400 cm-1) from CDRI Lucknow. Mass spectra were obtained
through JEOL SX-102 (FAB), CDRI Lucknow. PMR spectra
of selected samples were recorded on t scale through Bruker
Avance IT 400 NMR spectrometer SAIF Punjab University
Chandigarh. TGA were carried on Mettler from Central
instrumentation Laboratory from NIPER Mohali.
INTRODUCTION
Th(IV) and UO2(VI) metal complexes with variety of
Schiff bases and exhibit high coordination numbers. Their
enormous complex forming tendency is attributed to the vacant
inner 5f sub shell which can expand greatly to accommodate a
number of ligands. The greater spatial extension of 5f orbitals
of actinides along with the fact that these orbitals are diffused
at the periphery of atom make them suitable to form number
of complexes because in such situation the orbitals are disturbed
by ligands. Hence actinide complexes are ionic in nature along
with covalent characters1.
Synthesis of ligand: Solution of 4-methoxybenzaldehyde
and 4-chlorobenzaldehyde (1 mmol) in ca. 30 mL ethanol was
mixed with solution of 2-amino pyridine (1 mmol) each in ca.
30 mL ethanol. The resultant solutions were refluxed in RB
flask fitted with water condenser for 6 h. On cooling Schiff
bases crystallized out which were filtered and re-crystallized
with proper solvent. The structure of ligands are given in Figs.
1 and 2.
Nitrogen donor ligands particularly Schiff bases have been
of great interest for various coordination chemist who used
them as ligands against thorium(IV) and dioxouranium(VI)
metal to form complexes. Schiff bases form a class of compounds
with azomethine (-C=N-) group which can be obtained by
condensation of primary amine and carbonyl compounds by
elimination of water molecule. In this present work two Schiff
base were derived from 2-amino pyridine and p-methoxy
benzaldehyde and p-chloro benzaldehyde.
H3CO
CH=N
N
2-MBAPy
Fig. 1. 2N-[4-Methoxybenzalidiene]aminopyridine
EXPERIMENTAL
Cl
CH=N
All the chemicals used were of AR grade and were used
with further purification where ever required. Elemental analysis
were carried on ElementalVario EL III Carlo Erba 1108 CDRI
Lucknow. Conductivity measurements for the complexes have
been carried out on Elico 01/01 cell type conductivity bridge.
Molecular weights were determined in freezing PhNO2 using
Beckmann thermometer method cryoscopically in the laboratory.
N
2-CBAPy
Fig. 2. 2N-[4-Chlorobenzalidiene]aminopyridine
Preparation of complexes: Th4+ and UO22+ complexes
of Schiff base were prepared by refluxing the nitrate, iodide,
isothiocynate, perchlorate salts of Th4+ and UO22+ in proper
Agnihotri, Sonal
