R. Vafazadeh et al. / Polyhedron 29 (2010) 1810–1814
1811
4.60%. IR (KBr, cmꢀ1):
m
C@N = 1605,
m
C–O = 1326. Electronic spectra
X
in CHCl3: d–d, kmax (e
) 663 nm (143 Mꢀ1 cmꢀ1).
N
2.4.7. bis(N-4-methylphenyl-salicydenaminato)copper(II) (7)
Brown plate-like crystals. Yield 45%. Anal. Calc. for C28H24Cu-
N2O2: C, 69.48; H, 5.00; N, 5.79. Found: C, 69.47; H, 4.90; N,
O
Cu
O
N
5.71%. IR (KBr, cmꢀ1):
in CHCl3: d–d, kmax
m
C@N = 1612,
mC–O = 1331. Electronic spectra
(e
) 667 nm (250 Mꢀ1 cmꢀ1).
X
2.4.8. bis(N-3-methylphenyl-salicydenaminato)copper(II) (8)
Olivaceous cubic crystals. Yield 40%. Anal. Calc. for C28H24Cu-
N2O2: C, 69.48; H, 5.00; N, 5.79. Found: C, 69.23; H, 4.92; N,
X=H, (1); X=4-Cl, (2); X=3-Cl, (3); X=2-Cl, (4); X=4-Br, (5); X=2-Br, (6);
X=4-CH3, (7); X=3-CH3, (8); X=2-CH3, (9)
5.81%. IR (KBr, cmꢀ1):
in CHCl3: d–d, kmax
m
C@N = 1602,
mC–O = 1324. Electronic spectra
Scheme 1. The structure of studied complexes.
(e
) 665 nm (251 Mꢀ1 cmꢀ1).
temperature for 30 min gave rise to yellow micro crystals, yield
80%–90% (dependent on amines). The micro crystals were filtered
off and re-crystallization has been performed in diethyl ether solu-
tion at room temperature.
2.4.9. bis(N-2-methylphenyl-salicydenaminato)copper(II) (9)
Brown plate-like crystals. Yield 40%. Anal. Calc. for C28H24Cu-
N2O2: C, 69.48; H, 5.00; N, 5.79. Found: C, 69.57; H, 4.80; N,
5.85%. IR (KBr, cmꢀ1):
in CHCl3: d–d, kmax
m
C@N = 1607,
mC–O = 1326. Electronic spectra
(e
) 635 nm (148 Mꢀ1 cmꢀ1).
2.4. Syntheses of complexes (1–9)
2.5. X-ray crystallography
The copper(II) complexes were synthesized in a similar manner
using a method described elsewhere [15,16]. Thus, 2.5 mmol
(0.499 g) of copper(II) acetate monohydrate was slowly added to
a methanol solution (50 ml) of the relate Schiff base (5 mmol)
and the resulting solution was stirred for 1 h at room temperature.
The resulting brown or green-brown precipitates were collected by
filtration, washed with 10 ml of methanol and recrystallized from
dichloromethane/acetone (1:1 v/v).
Diffraction images were measured on a Nonius KappaCCD dif-
fractometer (Mo Ka, graphite monochromator, k = 0.71073 Å) and
data extracted using the DENZO package [17]. Structure solution
was by direct methods (SIR92) [18] and refinement was performed
using the CRYSTALS program package [19]. Atomic coordinates, bond
lengths and angles and displacement parameters have been depos-
ited at the Cambridge Crystallographic Data Centre. Crystallo-
graphic data for 6 are summarized in Table 1.
2.4.1. bis(N-phenyl-salicydenaminato)copper(II) (1)
Brown plate-like crystals. Yield 46%. Anal. Calc. for C26H20Cu-
N2O2: C, 68.48; H, 4.42; N, 6.14. Found: C, 68.61; H, 4.29; N,
3. Result and discussion
6.12%. IR (KBr, cmꢀ1):
in CHCl3: d–d, kmax
m
C@N = 1608,
mC–O = 1329. Electronic spectra
The reactions between salicylaldehyde and the appropriate
amine in methanol at room temperature yield Schiff base ligands.
The reaction between the Schiff base and Cu(CH3COO)2.H2O is fast
at room temperature and results in the formation of green-brown
neutral di-ligand complexes of copper(II) in good yield. The purity
of the complexes was checked by C, H, N elemental analyses and
were characterized by IR and UV–Vis spectroscopy.
(e
) 666 nm (243 Mꢀ1 cmꢀ1).
2.4.2. bis(N-4-chlorophenyl-salicydenaminato)copper(II) (2)
Brown plate-like crystals. Yield 50%. Anal. Calcd. for
C26H18Cl2CuN2O2: C, 59.50; H, 3.46; N, 5.34. Found: C, 59.53; H,
3.30; N, 5.24%. IR (KBr, cmꢀ1):
spectra in CHCl3: d–d, kmax
m
C@N = 1607,
mC–O = 1326. Electronic
(e
) 665 nm (240 Mꢀ1 cmꢀ1).
Table 1
2.4.3. bis(N-3-chlorophenyl-salicydenaminato)copper(II) (3)
Brown plate-like crystals. Yield 45%. Anal. Calc. for C26H18Cl2Cu-
N2O2: C, 59.50; H, 3.46; N, 5.34. Found: C, 59.40; H, 3.45; N, 5.38%.
Crystallographic data for 6.
Compound
6
Chemical formula
Formula weight
T (K)
Space group
Unit cell dimensions
a (Å)
C26H18Br2CuN2O2
613.80
200
IR (KBr, cmꢀ1):
m
C@N = 1607,
mC–O = 1322. Electronic spectra in
CHCl3: d–d, kmax (e
) 659 nm (200 Mꢀ1 cmꢀ1).
ꢀ
triclinic, P1 Z = 2
2.4.4. bis(N-2-chlrophenyl-salicydenaminato)copper(II) (4)
9.5210 (8)
10.6221 (7)
12.4571 (8)
68.012 (5)
85.808 (6)
82.001 (5)
1156.52 (15)
Green-brown plate-like crystals. Yield 45%. Anal. Calc. for
C26H18Cl2CuN2O2: C, 59.50; H, 3.46; N, 5.34. Found: C, 59.37; H,
b (Å)
c (Å)
3.43; N, 5.38%. IR (KBr, cmꢀ1):
spectra in CHCl3: d–d, kmax (e
m
C@N = 1606,
mC–O = 1326. Electronic
a
(°)
) 655 nm (123 Mꢀ1 cmꢀ1).
b (°)
c
(°)
V (Å3)
2.4.5. bis(N-4-bromophenyl-salicydenaminato)copper(II) (5)
Brown cubic crystals. Yield 50%. Anal. Calc. for C26H18Br2Cu-
N2O2: C, 50.88; H, 2.96; N, 4.56. Found: C, 50.92; H, 2.79; N,
Z
2
606
1.762
F (0 0 0)
DCalc (g cmꢀ3
)
Crystal size (mm)
l
h range for data collection (°)
0.42 ꢁ 0.22 ꢁ 0.07
4.49%. IR (KBr, cmꢀ1):
in CHCl3: d–d, kmax
m
C@N = 1606,
mC–O = 1327. Electronic spectra
(mmꢀ1
)
4.43
(e
) 665 nm (221 Mꢀ1 cmꢀ1).
3.2–27.6
Limiting indices
ꢀ12 6 h 6 12, ꢀ13 6 k 6 13, ꢀ15 6 l 6 16
R[F2 > 2
wR(F2)
r
(F2)]
0.041
0.104
2.4.6. bis(N-2-bromophenyl-salicydenaminato)copper(II) (6)
Brown cubic crystals. Yield 46%. Anal. Calc. for C26H18Br2Cu-
N2O2: C, 50.88; H, 2.96; N, 4.56. Found: C, 50.83; H, 2.92; N,
w = 1/[r
2(F2) + (0.03P)2 + 1.63P], where P = (max(Fo2; 0) + 2F2c )/3.