2
612
J. Rahchamani et al. / Polyhedron 30 (2011) 2611–2618
on a 500 MHz Bruker FT-NMR spectrometer using CDCl
3
and
crystalline material. M.p. 212 °C and the yield was 63%. Anal. Calc.
for C13 BrN : C, 40.83; H, 2.36; N, 14.66. Found: C, 40.62;
H,2.22; N, 14.14%. Selected IR data (
DMSO-d solvents; chemical shifts (d) are given in ppm. IR spectra
6
H
9
4 5
O
ꢀ1
were obtained as KBr plates using a Bruker FT-IR instrument and
UV–Vis spectra were obtained on a Shimadzu UV-1650PC spectro-
photometer. Elemental analysis (C, H, N) were performed using a
Heraeus Elemental Analyzer CHN-O-Rapid (Elemental-Analysesys-
teme, Gmbh, West Germany). A Metrohm 757 VA computerace
instrument was employed to obtain cyclic voltammograms in ace-
tonitrile at room temperature (25 °C) using 0.1 M tetra-n-butylam-
monium hexafluorophosphate solution as supporting electrolyte
m
/cm KBr): 3494, 3384 (
C@N). H NMR (500 MHz, DMSO-d ): 11.94 (1H, br,
OH); 8.68 (1H, s, CH@N); 7.82 (1H, s, HAr); 7.67 (1H, d, HAr); 7.60
(1H, d, HAr); 7.03 (1H, s, HAr); 7.01 (1H, s, HAr); 4.96 (2H, br, NH ).
m
N–
1
H
); 1612 (
m
6
2
2.3. Synthesis of tetradentate complexes
The complexes were synthesized by template method. The
proper amounts of the diamine, the desired salicylaldehyde deriv-
atives and VO(acac) were mixed and refluxed in ethanol until the
.
GC analyses were carried out by a GC-17A Shimadzu instrument.
2
2.2. Synthesis of the tridentate ligands
desired tetradentate complexes were precipitated.
2
.2.1. Synthesis of N-salicylidene-4,5-dinitro-1,2-phenylenediamine
0
1
2.3.1. Synthesis of {N,N -bis(salicylaldiminato)}oxidovanadium(IV)
(
HL )
1
VOLig ꢁ1.4 H
2
O
In a round-bottom two necked flask equipped with a reflux con-
0
.2 g of 4,5-dinitro-o-phenylenediamine (1 mmol) and 0.2 mL
-hydroxybenzaldehyde (2 mmol) were dissolved in 40 mL of
absolute ethanol and the solution was stirred and heated to the
boiling point in a two-necked round bottom flask equipped with
a reflux condenser, a magnetic stirrer and a dropping funnel. From
the dropping funnel was dripped a solution of 0.26 g (1 mmol) of
denser, a magnetic stirrer and a dropping funnel, 0.4 g of 4,5-dini-
tro-o-phenylenediamine (2 mmol) was dissolved in 40 mL of
absolute ethanol and was stirred and heated to the boiling point.
After 10 min, a solution of 0.2 mL of 2-hydroxybenzaldehyde
2
(
2 mmol) in 20 mL of absolute ethanol was added drop-wise from
the dropping funnel during approximately 20 min and the result-
ing yellow solution was stirred and refluxed for a further 60 min.
The resulting dark orange solid was recrystallized from absolute
ethanol and the crystalline target material was collected by suction
filtration, washed successively with cold ethanol and diethyl ether
and then air dried. M.p. 222 °C and the yield was 71%. Anal. Calc. for
2
bis(acetylacetonato)oxidovanadium(IV), (VO(acac) ) in 40 mL of
ethanol and then 1 mL of pyridine. A brown precipitate was ob-
tained after 90 min which was collected by suction filtration and
air dried. Recrystallization from acetonitrile yielded 31.3% of pure
target complex. Anal. Calc. for C20
N, 11.42. Found: C, 48.74; H, 3.18; N, 11.04%. Selected IR data (
14.8 4
H N O8.4V: C, 48.93; H, 3.02;
m
/
C
13 10 4 5
H N O : C, 51.65; H, 3.31; N, 18.54. Found: C, 51.39; H,3.40; N,
ꢀ1
ꢀ1
cm KBr): 3416 (
in CH CN [k, nm, (
23(34 246); 266(35 413).
m
O–H); 1609 (
m
C@N); 978 (
mV@O). UV–Vis spectrum
1
8.83%. Selected IR data (
m
/cm KBr): 3392, 3500 (
C@N). H NMR (500 MHz, DMSO-d ): 11.40 (1H, br, OH); 8.97
1H, s, CH@N); 7.94 (1H, s, HAr); 7.87 (1H, d, HAr), 7.44 (1H, m,
Ar); 7.13 (3H, br, HAr and NH ); 6.99 (2H, m, HAr).
mN–H); 1629
ꢀ
1 ꢀ1
1
3
e, l mol cm )]: 550(1146); 402(22 560);
(m
6
3
(
H
2
Table 1
2
.2.2. Synthesis of N-(4-methoxysalicylidene)-4,5-dinitro-1,2-
Crystal data, data collection and structure refinement.
2
phenylenediamine (HL )
L2
2
Compound
H
2
VOLig ꢁDMF
This compound was prepared following the same procedure as
HL1 except 4-methoxy-2-hydroxybenzaldehyde was used instead
of salicylaldehyde. M.p. 210 °C and the yield was 77%. The product
was recrystallized by slow evaporation of its solution in a mixture
of chloroform/ethyl CH
Formula
C
14
H
12
4
N O
6
25 23 5 10
C H N O V
604.42
monoclinic
Formula weight
Crystal system
Space group
a (Å)
332.28
triclinic
ꢀ
1
P2 /n
P1
CN/Water (1:4 v/v) at room temperature
7.709(2)
8.351(2)
13.447(2)
16.376(2)
24.025(3)
90
92.56(2)
90
5285.2(12)
8
1.519
3
2
b (Å)
and yellow crystals of HL suitable for X-ray crystallography were
obtained after two weeks. Anal. Calc. for C14 : C, 50.60; H,
.61; N, 16.87. Found: C, 50.44; H, 3.71; N, 16.55%. Selected IR data
c (Å)
11.699(3)
109.56(1)
91.80(2)
96.93(2)
702.4(3)
2
12 4 6
H N O
a
(°)
b (°)
(°)
3
ꢀ1
1
(m
/cm KBr): 3396, 3496 (
DMSO-d ): 11.85 (1H, br, OH); 8.87 (1H, s, CH@N); 7.90 (1H, s,
Ar); 7.73 (1H, d, HAr), 7.12 (1H, s, HAr); 7.06 (2H, br, NH ); 6.63
1H, d, HAr); 6.52 (1H, d, HAr).
mN–H); 1622 (
m
C@N). H NMR (500 MHz,
c
3
V (Å )
6
Z
D
H
(
2
(g cm 3
ꢀ
)
1.571
x
F(0 0 0)
l
344
1.077
2488
3.734
(mmꢀ1)
2
.2.3. Synthesis of N-(3-methoxysalicylidene)-4,5-dinitro-1,2-
H
range (°)
4.0–73.1
3.3–71.9
3
hkl range
ꢀ9 6 h 6 9
ꢀ15 6 h 6 16
ꢀ18 6 k 6 20
ꢀ29 6 l 6 27
phenylenediamine (HL )
ꢀ
ꢀ
10 6 k 6 10
14 6 l 6 14
This compound was prepared following the same procedure as
HL1 except 3-methoxy-2-hydroxybenzaldehyde was used instead
of Salicylaldehyde. The target compound was obtained as a yellow
crystalline material. M.p. 234 °C and the yield was 71%. Anal. Calc.
Reflections
Collected
Unique (Rint
With I > 2r(I)
Number of parameters
11 927
2771(0.042)
2402
21 738
10 223(0.027)
8901
)
for C14
H
12
N
4
O
6
: C, 50.60; H, 3.61; N, 16.87. Found: C, 50.61; H,3.32;
ꢀ1
N, 16.52%. Selected IR data (
m
/cm KBr): 3494, 3346 (
C@N). H NMR (500 MHz, DMSO-d ): 11.28 (1H, br, OH); 8.98 (1H,
s, CH@N); 7.96 (1H, s, HAr); 7.45 (1H, dd, HAr); 7.19 (1H, d, HAr);
.13 (3H, br, HAr and NH ); 6.94 (1H, m, HAr).
m
N–H); 1626
265
740
1
(m
6
Weighting scheme
A
B
0.0874
0.1297
0.0500
14.8459
7
2
Final R index [I > 2
r
(I)]
R
1
= 0.045,
wR = 0.1305
= 0.050,
wR = 0.136
1.01
0.19/ꢀ0.27
R
1
= 0.081,
wR = 0.212
= 0.088,
wR = 0.216
2
2
2
.2.4. Synthesis of N-(5-bromosalicylidene)-4,5-dinitro-1,2-
R index [all data]
R
1
R
1
4
phenylenediamine (HL )
2
2
Goodness-of-fit (GOF) on F2
Maximum/minimum
1.211
0.74/ꢀ0.61
This compound was prepared following the same procedure as
HL1 except 5-bromo-2-hydroxybenzaldehyde was used instead of
Salicylaldehyde. The target compound was obtained as a yellow
D
q
ꢀ
3
(
e Å )