Synthesis, characterization and spectroscopic studies of a novel 2-[ (E)-[ (2, 4-dichlorophenyl)imino]methyl]phenol schiff base and its metal complexes

Article abstract of DOI:10.1155/2012/928162

A novel Schiff base 2-{ (E)-[ (2, 4-dichlorophenyl)imino]methyl}phenol (L_B) was synthesized from the condensation reaction of 2, 4-dichloroaniline with salicyladehyde in [1:1] ratio in the presence of glacial acetic acid as catalyst. Complexati

Full text of DOI:10.1155/2012/928162

ISSN: 0973-4945; CODEN ECJHAO
E-Journal of Chemistry
http://www.ejchem.net
2012, 9(3), 1543-1549
Synthesis, Characterization and Spectroscopic Studies
of A Novel 2-[(E)-[(2,4-
dichlorophenyl)imino]methyl]phenol Schiff Base and
Its Metal Complexes
*
EMAN TURKY SHAMKHY and ISAM HUSSAIN T. AL-KARKHI
Department of Basic Science, College of Dentistry, University of Baghdad, Bab Al-
Moazam, Baghdad - Iraq
bluesky_832000@yahoo.com
Received 2-Nov-2011; Accepted 7-Jan-2012
Abstract:
A
novel
Schiff
base
2-{(E)-[(2,4-
dichlorophenyl)imino]methyl}phenol (L ) was synthesized from the
B
condensation reaction of 2,4-dichloroaniline with salicyladehyde in [1:1] ratio
in the presence of glacial acetic acid as catalyst. Complexation reaction of this
Schiff base with copper (II), cobalt (II) as nitrate salts and with Rhodium (III)
as chloride salt to produce three coordinate metal complexes, with a Schiff
base: Metal ion ratio of 2:1. These compounds have been characterized by a
variety of physico-chemical and spectroscopic techniques. The ligand and its
metal complexes were expected to show an interesting bioactivity and
cytotoxicity.
Keywords: salicyladehyde , aniline, Schiff base.
Introduction
-
Schiff bases, which also known as azomethines because they have R-C=N-R group, has
been widely synthesized due to their important roles in biological systems. They are facing
an increasing interest because of their various applications, like biological properties
[
1-6]
.
Schiff bases were used as ligands in coordination chemistry due to their donation and
[
7-11]
chelating abilities
. Ligands and their metal complexes have a wide applications in
[12]
[13-14]
[15-17]
industry, especially in analytical reagents , dying
and
catalysis
. In this
research, we synthesized one Schiff base (L ) derived of 2,4-dichloroaniline with
B
salicyladehyde and complication reaction of this Schiff base with copper (II), cobalt (II) as
nitrate salts and with Rhodium (III) as chloride salt to produce three coordinate metal
complexes. Characterization to the prepared compounds has been done to them by using
different spectroscopic and analytical techniques.

1
544 Eman Turky Shamkhy
Materials and Methods
Materials
Chemicals that have been used in this research are: salicylaldehyde (BDH), 2,4-
dichloroaniline (BDH), Cupper(II) nitrate trihydrate (BDH), Cobalt (II)nitrate hexahydrate
(
fluka), Rhodium(III) trichloride hydrate (BDH). All chemicals were of analytical grade and
were used as supplied without any further purification. sulphoxide (DMSO) (99% BDH),
absolute ethanol (99.99%, BDH), dimethyl Diethyl ether (fluka), diethylether (fluka), glacial
acetic acid (BDH).
Physical Measurements
Melting points were carried out using Gallen kamp M.F.B 600.01. The infrared spectra of
the prepared compounds were recoded using FT-IR-8300-Shimadzu, in the wave length
-
1
range of (4000-400) cm . The metals content of the complexes were measured using atomic
absorption technique by Perkin-Elmer-5000. The electronic spectra of the prepared
compounds were obtained using (UV-Vis-160A) Shimadzu Spectrophotometer, of wave-
-
3
length (200-1100 nm) all prepared compounds were dissolved in (DMSO) at (10 M).
Carbon, hydrogen, nitrogen and sulfur analyses were carried out using a Leco CHNS-932
analyzer. The molar conductivity measurements were carried out using Wissenschaftlich-
Technisch Werk-statten 8120 Weilheim I.O.B, Drucker-Printer. The magnetic susceptibility
values were obtained at room temperature using (Magnetic Susceptibility Balance), of
Johnson mattey catalytic system division. The metals content of the complexes were
measured using atomic absorption technique by Perkin-Elmer-5000.
Preparation of 2-{(E)-[(2,4-dichlorophenyl)imino]methyl}phenol [L ] ligand:-
B
A mixture of (10 mmol) of salicylaldehyde with (10 mmol) of 2,4-dichloroaniline was
dissolved in (25 mL) of absolute ethanol. Then, to this mixture, few drops of glacial acetic
acid were added as catalyst, the resulting mixture was refluxed for two hours. The resulting
precipitate was filtered, washed with diethyl ether and recrystallized. Then the product was
o
dried under vacuum oven at 40 C for two days. Pale green Schiff base collected with
melting point 75 ºC and yield (77%).
Preparation of the Metal Complexes of [L ]:-
B
A Solution of (0.94 mmol) Copper nitrate trihydrate, Cobalt nitrate hexahydrate, Rhodium
chloride monohydrate dissolved in (10 mL) of absolute ethanol was added to (1.88 mmol) of
[
LB] dissolved in (15 mL) of absolute ethanol. The mixture was refluxed with stirring for
three hours, the resulting precipitate was filtered and washed with diethyl ether and
o
recrystallized from hot ethanol then dried under vacuum at 40 C for two days. Yields: ca.
7
4-80%.
Results and Discussion
The new Schiff base, 2-{(E)-[(2,4-dichlorophenyl)imino]methyl}phenol [L ] ligand has
B
been prepared and characterized successfully. Three metal complexes were also synthesized
by reacting metal ions salts Cu(II), Co(II), and Rh(III) with the new ligand.
Scheme 1 shows the synthesis route for the novel Schiff base.

Synthesis, Characterization and Spectroscopic Studies of A Novel 1545
Scheme 1. Synthesis of L ligand.
B
All the physical measurements of the synthesized ligand (L ), the metal complexes and the
B
expected formula of the synthesized complexes are shown in Table (1). The data are very
near to the expected formula to all the prepared compounds.
Table 1. Physical properties of the synthesized compounds.
Meltin
g point
(°C)
% Found(calculated)
Compound
Colour
Yield
%
±
1 °C
%C
%H
%N
%O
%M
LB
Pale
green
77
74
80
76
75
56.34
3.63
5.15
6.62
(6.01)
-
C H Cl NO
(58.67 (3.41 (5.26
1
3
9
2
)
)
)
LBCu(II)
Brown
191
151
211
52.69
3.78
4.18
10.85
10.85
[
Cu(L ) (H O) ]
(49.58 (3.20 (4.45 (10.16 (10.09
B 2
2
2
)
)
)
)
)
LBCo(II)
Co(L ) (H O) ].3H
2
Yellowis
h green
49.01
4.23
4.97
17.11
9.45
[
(45.97 (3.86 (4.12 (16.49 (8.68)
B 2
2
2
O
)
)
)
)
LBRh(III)
Rh (L ) (Cl )] 4H O
Red
47.48
3.19
4.27
9.62
(9.08) (14.60
)
14.03
[
(44.32 (2.86 (3.98
2
B 4
2
2
)
)
)

1
546 Eman Turky Shamkhy
The FT-IR Spectra of [L ] and The Metal Complexes:-
B
-
1
The F.T.IR spectrum of [L ] shows a broad band appearing at (3456 cm ) has been assigned
B
to stretching vibration of the hydrogen bonded of (OH) group in the ligand [L ]. A broad
B
-
1
band was observed at (665 cm ) assigned to the hydrogen bonded out-of the plane of (O-H)
(
18, 19)
-1
bending vibration
. The medium to strong intensity bands appear at (1280 cm ) which
(
18, 20)
-1
assigned to the phenolic (C-O)
stretching mode which was changed from (1280cm ) to
this indicates displacement the
metal ion by the hydrogen-phenol . The (1554 cm ) band is due to the presence of (C=C)
of aromatic system . The two strong band at (788 and 819) cm are due to the ortho and
para substitution respectively . The ν(C-H) of the aromatic moiety appeared in (2758 cm
-
1
(21, 22)
(
1325cm ) after complexation with central metal ion
(
23)
-1
(
24)
-1
(
25)
-
1
(26, 22)
)
.
-
1
The band at (1614 cm ) is due to (-C=N-) azomethine group stretching which shifted to
(
27, 28)
(23, 29)
lower value ca.,1604 in the metal complexes
due to metal-ligand coordination
.
-
1
The new bands which have been observed around (530, 524, and 570) cm were
attributed to ν (Cu-N), ν (Co-N), and ν (Rh-N) respectively , while the bands at (455, 450
and 447) cm-1 attribute to (Cu-O), ν (Co-O) and ν (Rh-O) respectively
(
30)
(
31, 32)
.
-
1
-1
The strong sharp band at (829 cm and 729 cm ) indicates the presence of H O
2
molecules ν (Cu-H O and Co-H O) in the coordination of [L Cu(II) and L Co(II)]
2
2
B
B
(
31)
complexes respectively
appeared at (3422 cm ) refer to the presence of water molecules out of the coordination
sphere in the structure of [L Rh(III)] complex.
. The spectrum of Rh(III) complex shows a broad band which
-
1
(
32)
Table 2 shows the necessary bands of the
B
new ligand and the metal complexes.
-
1
Table 2. The most significant IR bands of [L ] and its metal complexes in (cm ).
B
Compoun ν (O- ν(C=
H) N)
Phenoli
ν(C=C)
ν(C-H)
Orth Par ν(M ν(M
d
c (C-O) Aromati Aromati
o
a
-N)
-O)
c
c
sub. sub.
C-Cl
C-
Cl
LB
3454 1614
1280
1325
1554
2758
748 819
-
-
LBCu(II)
-
1604
1579
3012
754
530 455
524 450
8
8
29
50
LBCo(II)
LBRh(III)
-
-
1604
1604
1325
1330
1531
1521
2877
2923
750
756 827 570 447

Synthesis, Characterization and Spectroscopic Studies of A Novel 1547
Table 3. Magnetic moments, Conductivity and Suggested Structures for
-
3
Complexes in (10 M) DMSO solvent.
Magnetic moment Conductivity λ max (log ε) (nm)
Complex
LB
Suggested
structure
-
1
μeff. (B.M.)
μS.cm
-
-
405(2.8 ), 327(3.7),
72(3.2)
-
2
LBCu(II)
LBCo(II)
1.83
4.85
15.3
13.4
657( 0.01)
Octahedral
Octahedral
671(0.01), 388(0.3)
LBRh(III)
Diamagnetic
18.2
721(0.003 ),
Octahedral
4
64(0.6), 337(0.2)
Study of the Magnetic Susceptibility and Conductivity Measurements
The conductivity to all the complexes was measured; all the complexes are not ionic as
shown in Table 3. The value of ( µ ) that have been measured for all the metal complex it
eff.
(
33, 34)
was found (1.83 B.M, 4.85 BM) for Cu(II) and Co(II) complexes respectively,
. The
Rhodium (III) complex is diamagnetic which refer to strong field. These values are in the
(
34)
range of mononuclear octahedral geometry for all the metal complexes
.
Study of the Electronic Spectra
The Electronic spectra measurements of the ligand and the metal complexes are shown in
-
3
Table 3, the data was collected in (UV-Vis) region in DMSO solvent at (10 M).
The Schiff base have been generally exhibit in three main bands, the first absorption
*
band appeared at 272 nm which can be attributed to (π → π ) transition for the aromatic
*
system while the second absorption band attribute to (π → π ) transition of imines group,
(
35)
which appeared at 327 nm . These bands were not significantly affected by chelating.
*)
(36)
The third absorption band appeared at 405 nm assigned to (n→π transition .Which
was shifted to a longer wavelength (red shift) upon formation of the complexes. This shift
may be attributed to the donation of the lone pairs of the nitrogen atoms of the Schiff base to
(
37)
the metal ion (N:→M)
.
The electronic spectra of Cu(II) compounds show single broad absorption band in the
(
38)
region 657 nm . The brown color [L Cu(II)] which suggest a strong field complex and
B
(
38, 39)
show a broad band
Teller distortion )
at 657 nm this band refer to distort octahedral geometry (Jahn-
(
38, 40)
2
2
which can be assigned to Eg → T g transitions.
2
The Co(II) complex which shows two bands, one at 671 nm and 388 nm which was
4
4
4
3
4
assigned to the transition [ν T g (F) → A g (F)] and [ν T g(F) → T g(P)], respectively.
2
1
2
1
1
The electronic spectra of brown of [L Rh(III)] complex, shows three absorption band at
B
1
1
1
1
4
64 nm, 337 nm which can be assigned to [ν1 A1g → T , and ν A → T ] transitions,
1g 2 1g 2g
while the third weak absorption band appear at (721 nm) which can be assigned to
1
3
transitions [ A → T ]. These transitions agreed well with low spin and octahedral
1
g
1g
(
38, 41)
geometry for this complex
.
The expected structures of the new metal complexes are shown in the Figure 1.

1
548 Eman Turky Shamkhy
Figure 1. Expected structures of Cu(II), Co(II), and Rh(III) complexes.
References
1
.
Walsh, O.M.; Meegan, M.J.; Prendergast, R.M.; Nakib, T.A. Eur. J. Med. Chem.
996, 31, 989.
1
2
.
Odabasoglu, M.; Arslan, F.; Ölmez, H.; Büyükgüngör, O. Dyes and Pigments 2007,
5, 507.
7
3
4
5
6
.
.
.
.
Samadhiya, S.; Halve, A., Orient. J. Chem. 2001, 17, 119.
Pandeya, S.N.; Sriram, D.; Nath, G.; DeClercq, E. Eur. J. Pharm. Sci. 1999, 9, 25.
Singh, N.K.; Singh, S.B. Indian J. Chem. 2001, 40A, 1070.
Vicini, P.; Geronikaki, A.; Incerti, M.; Busonera, B.; Poni, G.; Cabras, C.A.; Colla,
P.L. Bioorg. Med. Chem. 2003, 11, 4785.
7
8
.
.
.
Tarafder, M.T.H.; Jin, K.T.; Crouse, K.A.; Ali, A.M.; Yamin, B.M.; Fun, H.-K.
Polyhedron 2002, 21, 2547.
Mahmoud, M.R.; El-Gyar, S.A.; Mousrafa, A.A.; Shaker, A. Polyhedron 1987, 6,
1
017.
9
1
1
1
1
Cozzi, P.G. Chem. Soc. Rev. 2004, 33, 410.
0. Qing-Yu, H.; Zheng-Hua, M.; Ya-Me, Z. J. Coord. Chem. 1990, 21, 199.
1. Celik, Ö.; Ulusoy, M.; Tas, E.; Ide, S. Anal. Sciences 2007, 23, x185.
2. Tantaru, G.; Dorneanu, V.; Stan, M. J. Pharm. Biomed. Anal. 2002, 27, 827.
3. Papie, S.; Kaprivanae, N.; Grabarie, Z.; Paracosterman, D. Dyes and Pigments 1994,
2
5, 229.

Synthesis, Characterization and Spectroscopic Studies of A Novel 1549
1
1
1
4. Nejati, K.; Rezvani, Z.; Massoumi, B. Dyes and Pigments 2007, 75, 653.
5. Boghaei, D.M.; Mohebi, S. Tetrahedron 2002, 58, 5357.
6. Mc Auliffe, C.A.; Parish, R.V.; Abu-El-Wafa, S.M.; Issa, R.M. Inorg. Chim. Acta
1
986, 115, 91.
1
1
7. Abu-El-Wafa, S.M.; Issa, R.M. Bull. Soc. Chim. Fr. 1991, 128, 805.
8. Silverstein R, Bassler G and Morrill T. Spectrometric Identification of Organic
Chemistry, John Wiley and Sons, (1981).
1
2
2
9. Toyssie P and Charette J, J. Spectrochim. Acta.; 19, 1407, (1963).
0. Ruddick J.N and Sams J.R, J. Organomet. Chem.; 60, 233, (1973).
1. Zolfaghar R., Leili R.A., Kamellia N. and Seyed M. Acta Chem. Slov, 51, 675-677,
(
2004).
2
2
2
2
2. El-Sonbati A.Z and El-Bindary A.A. Polish J. Chem.; 74, (621-630), (2000).
3. Xishi T., Xianhong Y., Qiang C. and Minyu T. Molecules; 8, 439-440, (2003).
4. Abd-Elzaher M.M. J. Chinese Chem. Soc.; 48(2), 153-160, (2001).
5. Scheinmann I.F. Spectroscopic Methods for the Identification of Organic Compoun",
Pergamon press; 2,(1973).
2
2
2
6. Yildirim T.and Atakol O., Cryst. Res. Technol.; 37, (12), 1352, (2002).
7. Carla S., Cristina F. and Baltazar de Castro. Molecules; 8, 894-895, (2003).
8. Joseph M, Sreekanth A, Suni V, Kurup MRP. Spectrochimica Acta—Part A:
Molecular and Biomolecular Spectroscopy; 64(3), 637- 641 (2006).
2
9. Garnovski A.D., Ninorozhkin A.L. and Minkin V.I. Coord. Chem. Rev.; 126(1), 1-
6
9, (1993).
3
3
0. Chandra S. and Kumar R. Spectrochimica Acta , Part A (61), 437, (2005).
1. Nakamoto N., "Infrared and Raman Spectra of Inorganic and Coordination
compounds", 4th Ed., John Wiley and Sons, Inc., New York, (1986).
2. Stuart B., George W. and P. Mcintyre, "Modern Infrared Spectroscopy", John Wiely
and Sons, New York (1996).
3. Ainsceugh E.W, Brodie A.M., Denny W.A., Finlay J.G., and Renford J.D, J. Inorg.
Biochem.; 77, 125, (1999).
4. Insco E.W., Brodie A.M., Denny W.A., Finlay J.G and Ranford J.D. J. Indian
Biochem.; 70, 175-185, (1998).
3
3
3
3
3
3
5. William Kemp, "Organic Spectroscopy", 2nd Edition, (1987).
6. Saydam S., Yilmaz E. and Fen F.U. Ve Muh Bilimleri Dergisi; 12(2), 193, (2000).
7. Antonov L., Vladimirova M., Stanoeva E., Fabian W.F. and Ballester L. J. Incl.
phenom. Mol. Recog. Chem., 40, 23, (2001).
3
3
4
4
8. Greenwood N.N and A. Earnshaw, "Chemistry of Elements" pergamon
1984).
9. Williams, D. H.; and Fleming, I., "Spectroscopic methods in organic Chemistry'' Mc.
Graw-Hill book, (1973).
0. F. A. Cotton and G. Wilkinson, "Advanced Inorganic Chemistry", 4th Ed., John
Wiley and Sons, Chichester, Toronto, Singapore, New York.
1. Sharma K., and Srivastava A. "Spectroscopic, Thermal and Biological Studies on
Some Trivalent Ruthenium and Rhodium (NS) Chelating Thiosemicarbazone
Complexes" Bioinorg Chem. Appl.; 2007, 68374, (2007).
Press
(

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