organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2414-3146

2,2′-[(1E,1′E)-1,2-Phenyl­enebis(aza­nylyl­­idene)bis­(methanylyl­­idene)]bis­(4-bromo­phenol)

CROSSMARK_Color_square_no_text.svg

aLaboratoire d'Electrochimie, d'Ingénierie Moléculaire et de Catalyse Redox, Faculty of Technology, University of Ferhat Abbas Sétif-1, 19000-Sétif, Algeria
*Correspondence e-mail: k_ouari@yahoo.fr

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 11 January 2017; accepted 16 January 2017; online 20 January 2017)

In the title compound, C20H14Br2N2O2, there are two intra­molecular O—H⋯N hydrogen bonds forming S(6) ring motifs. The outer benzene rings are inclined to the central benzene ring by 39.09 (11) and 24.31 (11)°, and to one another by 37.12 (11)°. In the crystal, mol­ecules are linked by a short Br⋯O contact [3.1307 (19) Å], forming zigzag chains propagating along the a-axis direction. The chains are linked by weak offset ππ inter­actions [inter­centroid distance = 3.716 (1) Å], forming layers parallel to the ac plane.

3D view (loading...)
[Scheme 3D1]
Chemical scheme
[Scheme 1]

Structure description

Schiff base ligands are currently applied in coordination chemistry for the synthesis of transition metal complexes (Merzougui et al., 2016[Merzougui, M., Ouari, K. & Weiss, J. (2016). J. Mol. Struct. 1120, 239-244.]; Ourari et al., 2008[Ourari, A., Ouari, K., Khan, M. A. & Bouet, G. (2008). J. Coord. Chem. 61, 3846-3859.]; Ouari et al., 2010[Ouari, K., Ourari, A. & Weiss, J. (2010). J. Chem. Crystallogr. 40, 831-836.], 2015[Ouari, K., Bendia, S., Weiss, J. & Bailly, C. (2015). Spectrochim. Acta A Mol. Biomol. Spectrosc. 135, 624-631.]; Majumder et al., 2009[Majumder, S., Hazra, S., Dutta, S., Biswas, P. & Mohanta, S. (2009). Polyhedron, 28, 2473-2479.]; Salavati-Niasari et al., 2008[Salavati-Niasari, M., Shakouri-Arani, M. & Davar, F. (2008). Microporous Mesoporous Mater. 116, 77-85.]). A literature survey revealed that this kind of compound possesses diverse biological activities such as anti­anxiety, anti­depressant (Jubie et al., 2011[Jubie, S., Sikdar, P., Antony, S., Kalirajan, R., Gowramma, B., Gomathy, S. & Elango, K. (2011). Pak. J. Pharm. Sci. 24, 109-112.]) and anti-tumor, anti­bacterial, and fungicidal properties (Refat et al., 2008[Refat, M. S., El-Korashy, S. A., Kumar, D. N. & Ahmed, A. S. (2008). Spectrochim. Acta Part A, 70, 898-906.]; Kannan & Ramesh, 2006[Kannan, M. & Ramesh, R. (2006). Polyhedron, 25, 3095-3103.]). We report herein on the synthesis, crystal structure and spectroscopic analysis of the title Schiff base compound.

The title compound, illustrated in Fig. 1[link], is photochromic and the mol­ecule is not planar. The outer benzene rings (C8–C13 and C15–C20) are inclined to the central benzene ring (C1–C6) by 39.09 (11) and 24.31 (11)°, respectively, and to one another by 37.12 (11) °. There are two intra­molecular O—H⋯N hydrogen bonds forming S(6) ring motifs (Fig. 1[link] and Table 1[link]).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
O1—H1O⋯N1 0.87 (4) 1.77 (4) 2.594 (3) 157 (3)
O2—H2O⋯N2 0.81 (4) 1.89 (4) 2.613 (3) 149 (3)
[Figure 1]
Figure 1
The mol­ecular structure of the title compound, with the atom labelling and displacement ellipsoids drawn at the 50% probability level.

In the crystal, mol­ecules are linked by a short Br2⋯O1(x + [{1\over 2}], y, −z + [{1\over 2}]) contact [3.1307 (19) Å], forming zigzag chains propagating along the a-axis direction (Fig. 2[link]). Adjacent chains are linked by weak offset ππ inter­actions [Cg1⋯Cg2i,ii = 3.716 (1) Å; Cg1 and Cg2 are the centroids of the C1–C6 and C8–C13 rings, respectively; symmetry codes: (i) x + [{1\over 2}], −y + [{1\over 2}], −z; (ii) x − [{1\over 2}], −y + [{1\over 2}], −z], forming layers parallel to the ac plane (Fig. 3[link]).

[Figure 2]
Figure 2
A partial view along the b axis of the crystal packing of the title compound. The intra­molecular O—H⋯N hydrogen bonds (see Table 1[link]) and the short Br⋯O inter­actions are shown as dashed lines.
[Figure 3]
Figure 3
A view along the b axis of the crystal packing of the title compound. The short Br⋯O inter­actions are shown as dashed lines, and the offset ππ inter­actions as blue dashed double arrows. The H atoms have been omitted for clarity.

The spectroscopic analyses indicated: 1H NMR spectra in CDCl3 showed the aromatic protons as a multiplet in the range 6.80–8.00 p.p.m.. The azomethine proton resonance of the ligand appears as sets of sharp singlet at 8.54 p.p.m.. The hy­droxy group (OH) is observed at 13.20 p.p.m.. In the 13C NMR spectrum in CDCl3 the aromatic carbon appears in the range 108–161 p.p.m.. The carbon of the hy­droxy group appears at 160.32 p.p.m. and that of azomethine was observed at 162.40 p.p.m.. The DEPT-135 spectrum shows a disappearance of resonances at 110.53, 120.53, 142.17 and 160.32 p.p.m..

Synthesis and crystallization

The Schiff base ligand was prepared in 67% yield by condensation between 54 mg (0.5 mmol) of 1,2-di­amino­benzene and 201 mg (1 mmol) of 5-bromo­salicyl­aldehyde in methanol (15 ml). The mixture was refluxed and stirred under a nitro­gen atmosphere for 3 h. The obtained orange-yellow precipitate was filtered, washed with methanol and di­ethyl­ether and dried in vacuum over night. The isolated Schiff base ligand was recrystallized from dimethyl sulfoxide at room temperature, giving orange prismatic crystals.

1H NMR (CDCl3, δ p.p.m.): 13.20 (s, C—OH), 8.54 (s, CH=N), 6.80–8.00 (m, ArH); 13C NMR (CDCl3, δ p.p.m.): 162.46 (CH=N), 108–161 (C—Ar).

The DEPT-135 spectrum shows a disappearance of resonances at 110.53, 120.53, 142.17 and 160.32 p.p.m..

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2[link].

Table 2
Experimental details

Crystal data
Chemical formula C20H14Br2N2O2
Mr 474.15
Crystal system, space group Orthorhombic, Pbca
Temperature (K) 173
a, b, c (Å) 7.4379 (4), 18.7360 (11), 25.4469 (14)
V3) 3546.2 (3)
Z 8
Radiation type Mo Kα
μ (mm−1) 4.59
Crystal size (mm) 0.25 × 0.22 × 0.20
 
Data collection
Diffractometer Bruker APEXII CCD
Absorption correction Multi-scan (SADABS; Bruker, 2010[Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.])
Tmin, Tmax 0.684, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections 24680, 4695, 3533
Rint 0.038
(sin θ/λ)max−1) 0.681
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.072, 1.04
No. of reflections 4695
No. of parameters 243
H-atom treatment H atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3) 0.74, −0.82
Computer programs: APEX2 and SAINT (Bruker, 2010[Bruker (2010). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]), SHELXS2013 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]), Mercury (Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.], SHELXL2013 (Sheldrick, 2015[Sheldrick, G. M. (2015). Acta Cryst. C71, 3-8.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Structural data


Computing details top

Data collection: APEX2 (Bruker, 2010); cell refinement: SAINT (Bruker, 2010); data reduction: SAINT (Bruker, 2010); program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2015); molecular graphics: Mercury (Macrae et al., 2008; software used to prepare material for publication: SHELXL2013 (Sheldrick, 2015) and PLATON (Spek, 2009).

2,2'-[(1E,1'E)-1,2-Phenylenebis(azanylylidene)bis(methanylylidene)]bis(4-bromophenol) top
Crystal data top
C20H14Br2N2O2Dx = 1.776 Mg m3
Mr = 474.15Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 6049 reflections
a = 7.4379 (4) Åθ = 2.2–29.0°
b = 18.7360 (11) ŵ = 4.59 mm1
c = 25.4469 (14) ÅT = 173 K
V = 3546.2 (3) Å3Prism, orange
Z = 80.25 × 0.22 × 0.20 mm
F(000) = 1872
Data collection top
Bruker APEXII CCD
diffractometer
3533 reflections with I > 2σ(I)
Radiation source: fine focus sealed tubeRint = 0.038
φ and ω scansθmax = 29.0°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Bruker, 2010)
h = 1010
Tmin = 0.684, Tmax = 0.746k = 1625
24680 measured reflectionsl = 3434
4695 independent reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.037Hydrogen site location: mixed
wR(F2) = 0.072H atoms treated by a mixture of independent and constrained refinement
S = 1.04 w = 1/[σ2(Fo2) + (0.0242P)2 + 4.011P]
where P = (Fo2 + 2Fc2)/3
4695 reflections(Δ/σ)max = 0.002
243 parametersΔρmax = 0.74 e Å3
0 restraintsΔρmin = 0.82 e Å3
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.7048 (3)0.33306 (14)0.05240 (8)0.0191 (5)
C20.6445 (3)0.39534 (15)0.02823 (9)0.0249 (6)
H20.60140.39370.00690.030*
C30.6469 (3)0.45938 (15)0.05489 (10)0.0270 (6)
H30.60520.50150.03810.032*
C40.7100 (3)0.46261 (15)0.10622 (10)0.0266 (6)
H40.71250.50700.12430.032*
C50.7689 (3)0.40151 (14)0.13089 (9)0.0239 (6)
H50.81230.40400.16590.029*
C60.7654 (3)0.33587 (14)0.10490 (8)0.0192 (5)
C70.7319 (3)0.25946 (14)0.02176 (9)0.0207 (5)
H70.76650.30040.04130.025*
C80.7172 (3)0.19090 (14)0.04795 (8)0.0198 (5)
C90.6626 (3)0.12922 (14)0.02093 (9)0.0213 (5)
C100.6488 (3)0.06442 (15)0.04746 (9)0.0234 (5)
H100.61200.02280.02900.028*
C110.6882 (3)0.06019 (15)0.10042 (9)0.0242 (5)
H110.67880.01600.11850.029*
C120.7417 (4)0.12132 (15)0.12683 (9)0.0267 (6)
C130.7571 (3)0.18612 (15)0.10195 (9)0.0233 (5)
H130.79430.22720.12090.028*
C140.8331 (3)0.26220 (14)0.17711 (9)0.0216 (5)
H140.78350.29790.19930.026*
C150.9085 (3)0.19823 (13)0.20043 (9)0.0193 (5)
C160.9742 (3)0.14191 (14)0.16938 (9)0.0218 (5)
C171.0386 (3)0.08025 (15)0.19341 (9)0.0246 (6)
H171.08110.04180.17250.029*
C181.0408 (3)0.07479 (15)0.24765 (10)0.0254 (6)
H181.08510.03270.26390.030*
C190.9781 (3)0.13082 (14)0.27826 (9)0.0216 (5)
C200.9118 (3)0.19168 (14)0.25534 (9)0.0206 (5)
H200.86810.22950.27670.025*
N10.6987 (3)0.26546 (11)0.02769 (7)0.0204 (4)
N20.8315 (3)0.27181 (11)0.12698 (7)0.0195 (4)
O10.6211 (3)0.13052 (12)0.03072 (7)0.0320 (5)
O20.9777 (3)0.14578 (12)0.11642 (7)0.0290 (4)
Br10.78824 (7)0.11466 (2)0.20013 (2)0.05940 (13)
Br20.98786 (3)0.12364 (2)0.35269 (2)0.02677 (8)
H1O0.644 (5)0.175 (2)0.0388 (14)0.064 (13)*
H2O0.925 (5)0.182 (2)0.1081 (14)0.056 (12)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0168 (11)0.0203 (14)0.0203 (10)0.0007 (10)0.0021 (9)0.0003 (9)
C20.0250 (12)0.0270 (16)0.0228 (11)0.0021 (11)0.0015 (9)0.0032 (11)
C30.0235 (13)0.0231 (16)0.0345 (13)0.0039 (12)0.0022 (10)0.0050 (11)
C40.0275 (13)0.0198 (15)0.0324 (13)0.0022 (12)0.0035 (11)0.0047 (11)
C50.0260 (13)0.0231 (15)0.0227 (11)0.0018 (11)0.0006 (9)0.0036 (10)
C60.0187 (11)0.0199 (14)0.0190 (10)0.0001 (10)0.0018 (9)0.0013 (10)
C70.0214 (12)0.0211 (14)0.0198 (10)0.0007 (11)0.0016 (9)0.0022 (10)
C80.0192 (11)0.0238 (15)0.0163 (10)0.0003 (11)0.0009 (8)0.0008 (10)
C90.0181 (11)0.0267 (15)0.0192 (10)0.0001 (11)0.0006 (8)0.0028 (10)
C100.0221 (12)0.0203 (15)0.0279 (12)0.0029 (11)0.0023 (10)0.0039 (11)
C110.0274 (13)0.0200 (14)0.0252 (11)0.0014 (11)0.0021 (10)0.0029 (10)
C120.0380 (14)0.0258 (16)0.0163 (10)0.0008 (13)0.0006 (10)0.0011 (10)
C130.0295 (13)0.0229 (15)0.0174 (10)0.0026 (12)0.0020 (9)0.0041 (10)
C140.0258 (13)0.0198 (14)0.0191 (10)0.0007 (11)0.0003 (9)0.0038 (10)
C150.0196 (12)0.0186 (14)0.0196 (10)0.0030 (10)0.0014 (9)0.0011 (10)
C160.0210 (12)0.0255 (15)0.0188 (10)0.0015 (11)0.0011 (9)0.0024 (10)
C170.0232 (13)0.0225 (15)0.0281 (12)0.0024 (11)0.0002 (9)0.0054 (11)
C180.0224 (12)0.0225 (15)0.0312 (12)0.0021 (11)0.0033 (10)0.0037 (11)
C190.0208 (11)0.0245 (14)0.0194 (10)0.0061 (11)0.0021 (9)0.0024 (10)
C200.0207 (12)0.0221 (15)0.0191 (10)0.0003 (11)0.0001 (9)0.0019 (10)
N10.0237 (10)0.0203 (12)0.0172 (8)0.0009 (9)0.0019 (8)0.0005 (8)
N20.0216 (10)0.0191 (12)0.0179 (8)0.0012 (9)0.0014 (7)0.0014 (8)
O10.0480 (12)0.0282 (13)0.0198 (8)0.0048 (10)0.0085 (8)0.0033 (8)
O20.0356 (11)0.0320 (12)0.0196 (8)0.0078 (10)0.0022 (7)0.0041 (8)
Br10.1315 (4)0.02926 (18)0.01740 (12)0.0059 (2)0.01253 (16)0.00138 (12)
Br20.03229 (13)0.02816 (15)0.01988 (11)0.00264 (12)0.00415 (10)0.00563 (10)
Geometric parameters (Å, º) top
C1—C21.393 (4)C11—C121.386 (4)
C1—C61.411 (3)C11—H110.9500
C1—N11.415 (3)C12—C131.374 (4)
C2—C31.379 (4)C12—Br11.901 (2)
C2—H20.9500C13—H130.9500
C3—C41.389 (4)C14—N21.288 (3)
C3—H30.9500C14—C151.450 (3)
C4—C51.377 (4)C14—H140.9500
C4—H40.9500C15—C201.403 (3)
C5—C61.397 (4)C15—C161.406 (3)
C5—H50.9500C16—O21.350 (3)
C6—N21.414 (3)C16—C171.392 (4)
C7—N11.287 (3)C17—C181.384 (3)
C7—C81.451 (4)C17—H170.9500
C7—H70.9500C18—C191.388 (4)
C8—C91.405 (3)C18—H180.9500
C8—C131.409 (3)C19—C201.372 (3)
C9—O11.350 (3)C19—Br21.900 (2)
C9—C101.393 (4)C20—H200.9500
C10—C111.382 (3)O1—H1O0.87 (4)
C10—H100.9500O2—H2O0.81 (4)
C2—C1—C6119.3 (2)C12—C11—H11120.4
C2—C1—N1122.9 (2)C13—C12—C11122.0 (2)
C6—C1—N1117.7 (2)C13—C12—Br1119.66 (19)
C3—C2—C1120.5 (2)C11—C12—Br1118.27 (19)
C3—C2—H2119.8C12—C13—C8119.2 (2)
C1—C2—H2119.8C12—C13—H13120.4
C2—C3—C4120.3 (3)C8—C13—H13120.4
C2—C3—H3119.8N2—C14—C15121.6 (2)
C4—C3—H3119.8N2—C14—H14119.2
C5—C4—C3120.0 (2)C15—C14—H14119.2
C5—C4—H4120.0C20—C15—C16119.2 (2)
C3—C4—H4120.0C20—C15—C14119.1 (2)
C4—C5—C6120.7 (2)C16—C15—C14121.6 (2)
C4—C5—H5119.7O2—C16—C17118.5 (2)
C6—C5—H5119.7O2—C16—C15121.8 (2)
C5—C6—C1119.2 (2)C17—C16—C15119.7 (2)
C5—C6—N2123.6 (2)C18—C17—C16120.2 (2)
C1—C6—N2117.1 (2)C18—C17—H17119.9
N1—C7—C8120.8 (2)C16—C17—H17119.9
N1—C7—H7119.6C17—C18—C19120.0 (2)
C8—C7—H7119.6C17—C18—H18120.0
C9—C8—C13119.1 (2)C19—C18—H18120.0
C9—C8—C7121.7 (2)C20—C19—C18120.7 (2)
C13—C8—C7119.2 (2)C20—C19—Br2119.76 (19)
O1—C9—C10118.1 (2)C18—C19—Br2119.54 (19)
O1—C9—C8121.8 (2)C19—C20—C15120.2 (2)
C10—C9—C8120.1 (2)C19—C20—H20119.9
C11—C10—C9120.5 (2)C15—C20—H20119.9
C11—C10—H10119.8C7—N1—C1120.4 (2)
C9—C10—H10119.8C14—N2—C6121.0 (2)
C10—C11—C12119.1 (2)C9—O1—H1O102 (2)
C10—C11—H11120.4C16—O2—H2O107 (3)
C6—C1—C2—C31.2 (4)C9—C8—C13—C120.0 (4)
N1—C1—C2—C3177.4 (2)C7—C8—C13—C12179.5 (2)
C1—C2—C3—C40.1 (4)N2—C14—C15—C20177.9 (2)
C2—C3—C4—C50.6 (4)N2—C14—C15—C163.7 (4)
C3—C4—C5—C60.2 (4)C20—C15—C16—O2178.7 (2)
C4—C5—C6—C11.6 (4)C14—C15—C16—O22.9 (4)
C4—C5—C6—N2176.9 (2)C20—C15—C16—C171.1 (4)
C2—C1—C6—C52.0 (3)C14—C15—C16—C17177.3 (2)
N1—C1—C6—C5178.4 (2)O2—C16—C17—C18178.7 (2)
C2—C1—C6—N2177.7 (2)C15—C16—C17—C181.1 (4)
N1—C1—C6—N25.9 (3)C16—C17—C18—C190.2 (4)
N1—C7—C8—C91.5 (4)C17—C18—C19—C200.7 (4)
N1—C7—C8—C13179.1 (2)C17—C18—C19—Br2178.33 (19)
C13—C8—C9—O1179.5 (2)C18—C19—C20—C150.7 (4)
C7—C8—C9—O10.0 (4)Br2—C19—C20—C15178.32 (18)
C13—C8—C9—C100.1 (4)C16—C15—C20—C190.2 (4)
C7—C8—C9—C10179.6 (2)C14—C15—C20—C19178.2 (2)
O1—C9—C10—C11179.5 (2)C8—C7—N1—C1176.9 (2)
C8—C9—C10—C110.1 (4)C2—C1—N1—C737.9 (3)
C9—C10—C11—C120.0 (4)C6—C1—N1—C7145.9 (2)
C10—C11—C12—C130.1 (4)C15—C14—N2—C6177.0 (2)
C10—C11—C12—Br1178.15 (19)C5—C6—N2—C1427.9 (4)
C11—C12—C13—C80.1 (4)C1—C6—N2—C14156.6 (2)
Br1—C12—C13—C8178.13 (18)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1O···N10.87 (4)1.77 (4)2.594 (3)157 (3)
O2—H2O···N20.81 (4)1.89 (4)2.613 (3)149 (3)
 

Acknowledgements

The authors gratefully acknowledge financial support from the Algerian Ministry of Higher Education and Scientific Research. They also acknowledge the help of Dr Jean Weiss from the CLAC laboratory at the Institut de Chimie, Université de Strasbourg, France.

References

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