Synthesis and crystal structures of two novel complexes with N-[2-(5-bromo-2-hydroxybenzylideneamino)ethyl]- 4-methylbenzenesulfonamide as ligand

Article abstract of DOI:10.1007/s10870-010-9825-4

Two novel complexes constructed from the sulfonamide Schiff base ligand H₂L, N-[2-(5-bromo-2-hydroxybenzylideneamino) ethyl]-4-methylbenzene- sulfonamide, [Cu(HL)₂] (1) and [CuL(H₂O)] (2) are synthesized and characterized via X-ray single-crystal diffraction, elemental analysis, FT-IR and UV-Vis. 1 and 2 both form 1-D supramolecular architectures by π-pπ stacking interactions. 1 and 2 both crystallize in monoclinic, with space group C2/c and P2/c for 1 and 2, with unit cell parameters a = 27.640(18) A, b = 7.907(5) A, c = 17.945(14) A, 7β = 118.27(2)°, V = 3454(4) A³, Z = 4 for 1, and a = 16.758(5) A, b = 7.272(2) A, c = 15.080(4) A, β = 106.334(5)°, V = 1763.6(9) A³, Z = 4 for 2. Springer Science+Business Media, LLC 2010.

Full text of DOI:10.1007/s10870-010-9825-4

J Chem Crystallogr (2011) 41:12–16
DOI 10.1007/s10870-010-9825-4
ORIGINAL PAPER
Synthesis and Crystal Structures of Two Novel Complexes
with N-[2-(5-Bromo-2-Hydroxybenzylideneamino)Ethyl]-
4-Methylbenzenesulfonamide as Ligand
•
•
•
Shu-Ni Li Quan-Guo Zhai Man-Cheng Hu
Yu-Cheng Jiang
Received: 29 September 2009 / Accepted: 27 May 2010 / Published online: 12 June 2010
Ó Springer Science+Business Media, LLC 2010
Abstract Two novel complexes constructed from the sul-
fonamide Schiff base ligand H2L, N-[2-(5-bromo-2-hydro-
xybenzylideneamino)ethyl]-4-methylbenzene-sulfonamide,
[Cu(HL)2] (1) and [CuL(H2O)] (2) are synthesized and
characterized via X-ray single-crystal diffraction, elemental
analysis, FT-IR and UV–Vis. 1 and 2 both form 1-D supra-
molecular architectures by p–p stacking interactions. 1
and 2 both crystallize in monoclinic, with space group
C2/c and P2/c for 1 and 2, with unit cell parameters
chemistry and the application in biological and catalytic
fields [1–3]. Recent progresses made in Salen like Schiff
base complexes have been summarized [4–6]. Despite
advancement made in the salen like ligands and complexes,
little attention has been paid to asymmetric sulfonamide
Schiff base [7, 8], as research has focused mainly on two
types: those derived from the condensation of 2-tosylami-
nobenzaldehyde and diamines [9–13], and those from
condensation of N-tosyl-diamine and aldehydes [14–16].
As a part of our ongoing research of sulfonamide Schiff
base [17, 18], we select a sulfonamide Schiff base ligand,
N-[2-(5-bromo-2-hydroxybenzylideneamino)ethyl]-4-methyl-
benzenesulfonamide (H2L) (Scheme 1), to construct new
complexes. In this work, two novel complexes, [Cu(HL)2]
(1) and [CuL(H2O)] (2) have been prepared and char-
acterized by elemental analysis, X-ray single-crystal dif-
fraction, FT-IR, and UV–Vis measurements. p–p stacking
interactions lead 1 and 2 to present a 1-D supramolecular
structure.
˚
a = 27.640(18) A, b = 7.907(5) A, c = 17.945(14) A,
˚
˚
3
˚
b = 118.27(2)°, V = 3454(4) A , Z = 4 for 1, and a =
˚
˚
3
˚
16.758(5) A, b = 7.272(2) A, c = 15.080(4) A, b =
˚
106.334(5)°, V = 1763.6(9) A , Z = 4 for 2.
Keywords N-Tosylethylenediamine ꢀ Sulfonamide Schiff
base ꢀ Crystal structure ꢀ Supramolecular architecture
Introduction
Schiff base complexes attract many researchers’ interest
due to their importance in the development of coordination
Experimental Section
Ethylenediamine and Cu(NO3)2ꢀ3H2O were commercial
products and used without further purification. 5-Bromo-
salicylaldehyde was prepared by salicylaldehyde and liquid
bromine. N-Tosyl-ethylenediamine was synthesized accord-
ing to the literature method [19]. Cu(ClO4)2ꢀ6H2O was
obtained by the reaction of Cu2(OH)2CO3 and dilute HClO4.
C, H, and N elemental analysis was performed on a
Vario EL–III analyzer. Infrared spectra were recorded as
KBr pellet on a Nicolet Avatar 360 spectrophotometer in
the range 4000–400 cm-1. UV–Vis absorptions were
recorded on a SHIMADZU UV-1700 spectrophotometer.
S.-N. Li (&) ꢀ Q.-G. Zhai ꢀ M.-C. Hu ꢀ Y.-C. Jiang
Key Laboratory of Macromolecular Science of Shaanxi
Province, School of Chemistry and Materials Science,
Shaanxi Normal University, Xi’an 710062, Shaanxi,
People’s Republic of China
e-mail: lishuni@snnu.edu.cn
Q.-G. Zhai
e-mail: zhaiqg@snnu.edu.cn
M.-C. Hu
e-mail: hmch@snnu.edu.cn
Y.-C. Jiang
e-mail: jyc@snnu.edu.cn
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J Chem Crystallogr (2011) 41:12–16
13
Br
Table 1 Crystal data and structure refinements for complexes 1 and 2
O
Identification code
1
2
C
H
N
HN S
O
CH3
Empirical formula
Formula weight
Temperature (K)
C32H32Br2CuN4O6S2 C16H17BrCuN2O4S
OH
856.10
476.83
Scheme 1 N-[2-(5-Bromo-2-hydroxybenzylideneamino)ethyl]-4-
methylbenzenesulfonamide (H2L)
296(2)
296(2)
˚
Wavelength (A)
0.71073
Monoclinic
C2/c
0.71073
Monoclinic
P2/c
Crystal system
Space group
Synthesis of N-[2-(5-Bromo-2-
Hydroxybenzylideneamino)Ethyl]-4-
Methylbenzenesulfonamide (H2L)
˚
a (A)
27.640(18)
7.907(5)
17.945(14)
118.27(2)
3454(4)
4
16.758(5)
7.272(2)
15.080(4)
106.334(5)
1763.6(9)
4
˚
b (A)
˚
c (A)
b (°)
Volume (A )
An ethanol solution (60 mL) of N-tosyl-ethylenediamine
(2.14 g, 0.01 mol) and 5-bromo-salicylaldehyde (2.01 g,
0.01 mol) was refluxed for 1 h with constant stirring.
Yellow precipitate was collected by filtration. m.p. 157.2–
158.1 °C. Calculated for C16H17BrN2O3S: C 48.33%, H
4.279%, N 7.048%. Obtained: C 48.65%, H 4.323%, N
6.894%.
3
˚
Z
Dcalc. (Mg/m3)
1.646
1.796
Absorption coefficient
(mm-1
3.116
3.646
)
F(000)
1724
956
Crystal size (mm)
0.26 9 0.11 9 0.09 0.35 9 0.23 9 0.11
h range for data
collection (°)
Limiting indices
2.31–24.15
2.53–25.09
Synthesis of [Cu(HL)2] (1)
-31 B h B 31
-9 B k B 8
-18 B l B 20
7735
-16 B h B 20
-8 B k B 8
-17 B l B 17
8256
To a hot ethanol solution (25 mL) of H2L (0.532 g,
1 mmol), the ethanol solution of Cu(NO3)2ꢀ6H2O 0.242 g
(1 mmol) was added. The solution was reacted under
microwave condition for 15 min. The filtrate was set aside.
Brown needle crystals were collected after 2 days. Calcu-
lated for C32H32N4O6S2Br2Cu: C 44.89%, H 3.770%, N
6.540%. Obtained: C 44.37%, H 3.724%, N 6.528%.
Reflections collected
Independent reflections 2760 (Rint = 0.1260) 3096
(Rint = 0.0650)
Max. and min.
transmission
0.7668 and 0.4957
2760/0/185
0.936
0.7007 and 0.3626
3096/3/198
1.001
Data/restraints/
parameters
Goodness-of-fit on F2
Synthesis of [CuL(H2O)] (2)
Final R indices I [ 2r(I) R1 = 0.0538,
wR2 = 0.0731
R1 = 0.0585,
wR2 = 0.1435
To an ethanol solution (20 mL) of H2L (0.532 g, 1 mmol),
four drops of 0.01 mol L-1 NaOH aqueous solution were
added. Then the ethanol solution (10 mL) of Cu(ClO4)2ꢀ
6H2O (0.37 g, 1 mmol) was added dropwise to the above
solution while it was stirred. The mixture was brought to
react under microwave for 12 min. The filtrate was set still
and dark green block shaped crystals suitable for X-ray
diffraction were obtained after 2 days. It was collected by
filtration and air-dried. Calculated for C16H17N2O4SBrCu:
C 40.29%, H 3.568%, N 5.876%. Obtained: C 40.35%, H
3.510%, N 5.543%.
R indices (all data)
R1 = 0.1619,
wR2 = 0.0829
R1 = 0.0981,
wR2 = 0.1743
Largest diff. peak and
-3
0.481 and -0.418
0.722 and -0.772
˚
hole (e A
)
direct methods and refined by full-matrix least squares
based on F2, using SHELX-97 software [21]. All non-
hydrogen atoms were anisotropically refined. Hydrogen
atoms were included at geometrically calculated positions
and refined using a riding model except those bonded to the
water molecule. The H atoms of water molecular were
located in a difference map and refined with Uiso(H) =
1.5Ueq(O). The O–H and H_H distances were restrained
X-Ray Crystallographic Analysis
The crystal determination was performed at room temper-
ature on a Brucker-Smart APEX CCD diffractometer,
using graphite monochromated Mo Ka radiation (k =
˚
to be 0.82(2) and 1.32(2) A, respectively. The crystal data,
experimental details, refinement results and details of
structure determinations are shown in Table 1. Selected
bond lengths and bond angles are listed in Table 2.
´
˚
0.71073 A). Absorption corrections were made using the
SADABS program [20]. The structures were solved by
123

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J Chem Crystallogr (2011) 41:12–16
˚
Table 2 Selected bond lengths (A) and angles (°) for complexes 1
and 2
˚
Bond length (A)
Bond angles (°)
Complex 1
Complex 2
Cu1–O1
Cu1–N1
Cu1–O1
Cu1–N1
Cu1–O4
Cu1–N2
1.917(4)
O1–Cu1–N1
O1–Cu1–N1#1
O1–Cu1–N1
O1–Cu1–O4
N1–Cu1–N2
N1–Cu1–O4
O1–Cu1–N2
O4–Cu1–N2
91.1(2)
88.9(2)
92.6(2)
88.4(2)
84.8(3)
172.5(2)
175.3(2)
94.7(2)
2.010(6)
1.925(5)
1.926(6)
1.949(5)
1.985(7)
Symmetry transformations used to generate equivalent atoms: #1 -
x ? 3/2, -y ?1/2, -z
Fig. 2 1D chain structure of complexes 1 (a) and 2 (b)
[17] due to the electron withdrawing of Br in the ligand. The
coordination geometry around Cu(II) ion is a slightly dis-
torted square planar with the cis angles of 91.1(2) and
88.9(2)°. The ligand forms one Cu1–O1–C2–C1–C7–N1
six-membered chelate ring (deviation 0.06 A), and Cu2? lies
˚
˚
deviating from this calculated plane with -0.09 A. Complex
1 is extended into the final 1-D chain supramolecular struc-
ture as shown in Fig. 2a, through weak aromatic p–p
stacking interactions between phenyl rings from adjacent
organic ligands, with a center-to-center distance of about
˚
3.9 A. Moreover, the chelate ring–aromatic ring interactions
˚
(center-to-center distance of about 3.6 A) help to stabilize
Fig. 1 Molecular structure of complexes 1 (a) and 2 (b). Ellipsoids
are drawn at 40% probability. H atoms are omitted for clarity
the structure. This packing mode is much different from that
in [Cu(HL0)2] [17] because of the steric effect of Br group in
the ligand.
Results and Discussion
Crystal Structure of [Cu(HL)2] (1)
Crystal Structure of [CuL(H2O)] (2)
The molecular structure of complex 1 is presented in Fig. 1a.
The Cu(II) ion is tetra-coordinated by the imine nitrogen
atoms and phenolate oxygen atoms of two bidentate anionic
˚
Schiff base ligands. The Cu–Nimine (2.010(6) A) is longer
˚
than Cu–Ophenolate (1.917(4) A) distance. And the Cu–Nimine
The molecular structure of complex 2 is shown in Fig. 1b.
In the complex, the Cu(II) atom is coordinated to one
dianionic tridentate Schiff base ligand and one water
molecule. The Schiff base ligands coordinate to metal
through the imine and sulfonamide nitrogens and phenol
oxygen. The coordination geometry around Cu(II) ion is in
a slightly distorted square planar with N2O2 in a cis
arrangement. The cis angles are from 84.8(3) to 94.7(2)°
and 0 Cu–Ophenolate are both longer than those in [Cu
0
˚
(HL )2] (1.927(3) and 1.833(3) A, H2L = N-[2-(2-hydro-
xybenzylideneamino)ethyl]-4-methylbenzenesulfonamide)
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J Chem Crystallogr (2011) 41:12–16
15
and the trans angles are 172.5(2) and 175.3(2)°. The
of C=N group. Moreover, there exist weak d–d transition at
bond lengths increase in the sequential as Cu–Ophenolate
,
about 616 and 614 nm for complex 1 and 2.
Cu–Nimine, Cu–Owater and Cu–Namide. And in complex 2,
one-six-membered chelate ring Cu1–O1–C2–C1–C7–N1
and one-five-membered chelate ring Cu1–N1–C8–C9–N2
Supplementary Materials
2?
˚
(deviation 0.01 and 0.15 A, and Cu lies deviating from
˚
the calculated plane with -0.02 and -0.04 A for six-
CCDC 748158 and 748159 contain the supplementary
crystallographic data of 1 and 2 for this paper. These data
can be obtained free of charge from The Cambridge
Crystallographic Data Centre via http://www.ccdc.cam.ac.
uk/data_request/cif.
membered ring and five-membered ring, respectively) are
formed.
As shown in Fig. 2b, two molecules of complex 2 are
linked to form a centrosymmetric head-to-tail subunits by
the double weak p_p interactions between six-membered
chelate ring and aromatic ring (center-to-center distance of
Acknowledgments This work was supported by the Natural Sci-
ence Foundation of Shaanxi Province (Program No. 2009JQ2003) and
Fundamental Research Funds for the Central Universities (Program
No. GK200902011).
˚
about 3.6 A). Then the subunits are further connected to a
1D chain by the double weak p_p interactions of about
˚
3.7 A.
FT-IR spectra and UV–Vis absorption
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1633 cm-1. This suggests the coordination of the ligand to
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