Asian Journal of Chemistry; Vol. 25, No. 4 (2013), 1770-1772
http://dx.doi.org/10.14233/ajchem.2013.12720A
Synthesis, Characterization and Antibacterial Study of Co(II), Ni(II), Mn(II) and Cu(II)
Complexes Derived from 1,5-Dimethyl-4-{[1-(3-methyl-5-oxo-1-phenyl-4,5-dihydro
-1H-pyrazol-4-yl-idene)ethyl]amino}-2-phenyl-1H-pyrazol-3(2H)-one
*
HUALING ZHU , CHEN CHEN, JUNBIN WANG, ZHEN WEI and YANAN BAI
Department of Basic Science, Tianjin Agricultural College, Tianjin, P.R. China
*Corresponding author: Tel: +86 22 23781295; E-mail: zhuhualing2004@126.com
(Received: 13 September 2011;
Accepted: 3 October 2012)
AJC-12215
Co(II), Ni(II), Mn(II) and Cu(II) complexes derived from 1,5-dimethyl-4-{[1-(3-methyl-5-oxo-1-phenyl-4,5-dihydro-1H-pyrazol-4-yl-
idene)ethyl]amino}-2-phenyl-1H-pyrazol-3(2H)-one have been prepared and characterized by elemental analysis, spectroscopic data (IR
and UV) and H NMR. The antibacterial activity tests of the ligand and its metal complexes at different concentrations against Escherichia
coli and Bacillus subtilis were performed by using disc diffusion method. The results indicate that almost all the compounds have the
activity of inhibiting the growth of the two bacteria.
Key Words: Synthesis, Characterization, Complex, Antibacterial activity.
pyrazolone (25 m mol) and 4-amino antipyrine (25 m mol) in
ethanol (150 mL) over a steam bath for about 7 h, then the
solution was cooled down to room temperature.After five days,
pale yellow block was obtained. The block was separated,
washed with ethanol and dried over CaCl2 in vacuum.
Preparation of the complexes: The complexes of Co(II),
Ni(II), Mn(II) and Cu(II) have been formed by reacting
ethanolic solution of appropriate metal salts with ethanolic
solution of ligand in the molar ratio 1:2. The mixture was
heated on water bath for ca. 4h, then the mixture were cooled
under room temperature and solid coloured complexes sepa-
rated out which was filtered, washed with ethanol, dried over
CaCl2 in vacuum.
INTRODUCTION
Due to the potential application in medicine, biology,
materials and chemical industry, Schiff base and its metal
complexes are paid more attention. Most of the people are
interested in the researches of the synthesis and biological
activities of new Schiff bases. 4-Amino antipyrine derivatives
have been widely used in the analgesic1,2, antibacterial and
antitumor field and chemical analysis. 4-Amino antipyrine
schiff bases have showed unique properties and application in
the biological, clinical, pharmaceutical and analytical fields3,4.
Keeping in mind above biological significance of Schiff base
and in continuation of our earlier work5, we report herein the
preparation, characterization and anti-bacterial study of Co(II),
Ni(II), Mn(II) and Cu(II) complexes derived from 1,5-dimethyl-
4-{[1-(3-methyl-5-oxo-1-phenyl-4,5-dihydro- 1H- pyrazol-4-
yl-idene)ethyl]amino}-2-phenyl-1H-pyrazol-3(2H)-one.
RESULTS AND DISCUSSION
The IR spectra data of the free ligand and its metal comp-
lexes are given in Table-1. The spectra of the ligand exhibits
broad band at about 3427 cm-1 assigned to ν(N-H), accordingly
the band at 1530 cm-1 assigned to δ(N-H), there is also a band
at 1128 cm-1 assigned to ν(N-C). All these bands suggest that
the ligand exists in an enamine-keto form.
The brand 1623 cm-1 of the ligand is assigned to the C=O
of the antipyrine. This band disappears in the complex which
suggests the ligand is decomposed when the complex is
formed, the decomposed structure of the Cu complex is also
described by the article7. The IR spectrum of the ligand also
exhibits a strong and sharp band at 1672 cm-1 assigned to ν(C=O)
EXPERIMENTAL
1-Phenyl-3-methyl-4-acetyl-pyrazolone-5 (HPMAP) were
synthesized according to reported method6. Other chemicals
obtained as reagent grade were used without further purification,
IR spectra were recorded on Perkin-Elmer-1700 spectrophoto-
1
meter using KBr disc. H NMR spectrum were recorded on
FT-AC-80 spectrophotometer using TMS as internal standard.
Preparation of the ligand: The ligand was synthesized
by refluxing the mixture of 1-Phenyl-3-methyl-4-acetyl-
Zhu, Hualing
