research communications
N-[(Z)-(2-hydroxyphenyl)methylidene]aniline N-oxide
and Hirshfeld surface analysis ofaChemistry and Environmental Division, Manchester Metropolitan University, Manchester, M1 5GD, England, bChemistry Department, Faculty of Science, Minia University, 61519 El-Minia, Egypt, cChemistry Department, Faculty of Science, Assuit University, Egypt, dDepartment of Chemistry, Tulane University, New Orleans, LA 70118, USA, eChemistry Department, Faculty of Science, South Valley University, Egypt, fDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey, and gFaculty of Science, Department of Bio Chemistry, Beni Suef University, Beni Suef, Egypt
*Correspondence e-mail: shaabankamel@yahoo.com
The conformation of the title compound, C13H11NO2, is partially determined by a strong, intramolecular O—H⋯O hydrogen bond. The crystal packing consists of strongly corrugated layers parallel to the ac plane and associated through C—H⋯π(ring) interactions. A Hirshfeld surface analysis of the indicates that the most significant contributions to the crystal packing are from H⋯H (44.1%), C⋯H/H⋯C (29.4%) and O⋯H/H⋯O (17.3%) contacts.
Keywords: crystal structure; hydrogen bond; N-oxide; C—H⋯π(ring); nitrones; Hirshfeld surface analysis.
CCDC reference: 2082055
1. Chemical context
Nitrones are a very important class of organic compounds as a result of their medicinal and pharmaceutical applications. They show antifungal (Salman et al., 2013), antibacterial (Chakraborty et al., 2010), neuroprotective (Chioua et al., 2012) and anticancer (Floyd et al., 2011) activities. In addition, nitrone compounds are widely used as antioxidant agents (Al-Mowali et al., 2014) because of their ability to scavenge free radicals. Based on these findings and following our interest in this area, we report herein the of the title compound.
2. Structural commentary
The molecular structure of the title compound (Fig. 1) is almost planar, with maximum deviations of 0.398 (2) Å for O1 and −0.756 (2) Å for O2. The N1—O2 distance of 1.331 (2) Å is normal for a single bond and agrees well with those observed in other amine N-oxides. The dihedral angle between the aromatic rings (C1–C6 and C8–C13) is 1.94 (12) °. The torsion angles C2—C1—C7—N1, C1—C7—N1—C8, C1—C7—N1—O2, C7—N1—C8—C9 and O2—N1—C8–C-9 are −30.2 (3), −179.7 (2), −0.4 (3), 27.3 (3) and −152.0 (2)°, respectively. The conformation of the title compound is partially determined by a strong, intramolecular O1—H1⋯O2 hydrogen bond (Table 1).
3. Supramolecular features
In the crystal, C7—H7⋯O2i hydrogen bonds (Table 1) link the molecules, forming chains along the a-axis direction. The chains are linked into strongly corrugated sheets parallel to the ac plane by C10—H10⋯O2ii hydrogen bonds and C11—H11⋯Cg1iii interactions (Cg1 is the centroid of the C1–C6 hydroxyphenyl ring; Table 1 and Fig. 2). The sheets are stacked along the b-axis direction by C4—H4⋯Cg2iv interactions (Cg2 is the centroid of the C8–C13 phenyl ring; Table 1 and Figs. 2 and 3).
4. Hirshfeld surface analysis
A Hirshfeld surface analysis (Spackman & Jayatilaka, 2009) was carried out using CrystalExplorer17.5 (Turner et al., 2017) to visualize the intermolecular interactions in the title compound. The Hirshfeld surface mapped over dnorm (Fig. 4) shows the expected bright-red spots near atoms O1, O2, H7 and H10, which are involved in the C—H⋯O hydrogen-bonding interactions. The bright-red spot near O1 indicates its role as a hydrogen-bond acceptor to (C10)H10 (Fig. 4) and another red region near O2 correlates with the C7—H7⋯O2 interaction.
The two-dimensional fingerprint plots show the relative contributions of the various types of contacts to the Hirshfeld surface for the title compound (McKinnon et al., 2007). The plots (Fig. 5) reveal that H⋯H and C⋯H/H⋯C interactions make the greatest contributions to the surface contacts, while O⋯H/H⋯O, C⋯C, N⋯H/H⋯N, N⋯C/C⋯N and O⋯C/C⋯O contacts are less significant (Tables 2 and 3).
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5. Database survey
The four most closely related structures are (Z)-N-[(1,3-diphenyl-1H-pyrazol-4-yl)methanimine]-N-oxido (DEPVOM; Mohamed et al., 2018), (Z)-1,2-bis(3-bromophenyl)diazene 1-oxide (SIYHAK01; Goswami et al., 2018), (Z)-N-benzylidene-1-phenylmethanamine oxide hydrogen peroxide solvate (JELQOJ; Churakov et al., 2017) and (Z)-N-(2-chlorobenzylidene)aniline N-oxide (ERIXEJ; Fu et al., 2011).
In the crystal of DEPVOM, (101) layers are generated by C—H⋯O hydrogen bonds coupled with C—H⋯π(ring) and offset π–π stacking interactions. In the crystal of SIYHAK01, C—H⋯O and C—H⋯Br hydrogen bonds together with offset π–π interactions stack the molecules along the a-axis direction. In the crystal of JELQOJ, the organic and peroxide molecules are linked through both peroxide O—H donor groups to oxide O-atom acceptors, giving one-dimensional chains extending along the b-axis direction. Weak intermolecular C—H⋯O hydrogen-bonding interactions are also present. In the crystal of ERIXEJ, the molecule is stabilized by an intramolecular C—H⋯O hydrogen bond. The geometry about the C=N bond is Z [C—C—N—O torsion angle = −4.2 (3)°] and the phenyl and benzene rings are trans-oriented around the C=N bond. The phenyl and benzene rings make a dihedral angle of 56.99 (2)°.
6. Synthesis and crystallization
(Z)-(2-Hydroxyphenyl)methylidene]benzenimine N-oxide (nitrone) was prepared according to the reported procedures (Mobinikhaledi et al., 2005). 0.7 ml (6 mmol) of salicyaldehyde were added to a warmed solution of 0.8 g (6 mmol) N-phenylhydroxyamine in ethanol followed by stirring for 5 minutes, then standing at room temperature in the dark overnight gave the nitrone, which was recrystallized from ethanol in 53% yield; m.p. 387–388 K.
7. Refinement
Crystal and . The H atom of the OH group was found in difference-Fourier maps, and its positional parameters were fixed using the AFIX 3 instruction in SHELXL and were refined with the isotropic displacement parameter Uiso(H) = 1.5Ueq(O). The C-bound H atoms were positioned geometrically, with C—H = 0.95 Å, and constrained to ride on their parent atoms, withUiso(H) = 1.2Ueq(C). Attempts to determine the did not produce a definitive result, viz.: Flack x = 0.2 (3) by classical fit to all intensities 0.30 (14) from 611 selected quotients (Parsons' method). A round of TWIN/BASF gave BASF = 0.2 (4) with no improvement in the model.
details are presented in Table 4
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Supporting information
CCDC reference: 2082055
https://doi.org/10.1107/S2056989021004813/ey2006sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989021004813/ey2006Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989021004813/ey2006Isup3.cml
Data collection: APEX3 (Bruker, 2016); cell
SAINT (Bruker, 2016); data reduction: SAINT (Bruker, 2016); program(s) used to solve structure: SHELXT (Sheldrick, 2015a); program(s) used to refine structure: SHELXL (Sheldrick, 2015b); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and DIAMOND (Brandenburg & Putz, 2012); software used to prepare material for publication: PLATON (Spek, 2020).C13H11NO2 | F(000) = 224 |
Mr = 213.23 | Dx = 1.391 Mg m−3 |
Monoclinic, Pc | Cu Kα radiation, λ = 1.54178 Å |
a = 5.5391 (1) Å | Cell parameters from 3430 reflections |
b = 5.7873 (2) Å | θ = 5.6–72.4° |
c = 16.0859 (4) Å | µ = 0.77 mm−1 |
β = 99.067 (1)° | T = 150 K |
V = 509.21 (2) Å3 | Block, yellow |
Z = 2 | 0.19 × 0.17 × 0.15 mm |
Bruker D8 VENTURE PHOTON 100 CMOS diffractometer | 1654 independent reflections |
Radiation source: INCOATEC IµS micro–focus source | 1607 reflections with I > 2σ(I) |
Mirror monochromator | Rint = 0.023 |
Detector resolution: 10.4167 pixels mm-1 | θmax = 72.4°, θmin = 5.6° |
ω scans | h = −6→6 |
Absorption correction: multi-scan (SADABS; Krause et al., 2015) | k = −7→7 |
Tmin = 0.77, Tmax = 0.89 | l = −19→19 |
3578 measured reflections |
Refinement on F2 | Hydrogen site location: mixed |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.033 | w = 1/[σ2(Fo2) + (0.0441P)2 + 0.084P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.084 | (Δ/σ)max < 0.001 |
S = 1.06 | Δρmax = 0.18 e Å−3 |
1654 reflections | Δρmin = −0.18 e Å−3 |
145 parameters | Absolute structure: Flack x determined using 611 quotients [(I+)-(I-)]/[(I+)+(I-)] (Parsons et al., 2013). |
2 restraints | Absolute structure parameter: 0.30 (13) |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.8449 (3) | 0.3532 (3) | 0.64513 (12) | 0.0342 (4) | |
H1 | 0.841875 | 0.289527 | 0.589214 | 0.051* | |
O2 | 0.7828 (3) | 0.2215 (3) | 0.49662 (12) | 0.0338 (4) | |
N1 | 0.5424 (3) | 0.1864 (3) | 0.48272 (13) | 0.0267 (4) | |
C1 | 0.4520 (4) | 0.4953 (4) | 0.57874 (14) | 0.0260 (5) | |
C2 | 0.6705 (4) | 0.5169 (4) | 0.63617 (15) | 0.0280 (5) | |
C3 | 0.7030 (4) | 0.7093 (4) | 0.68930 (16) | 0.0328 (5) | |
H3 | 0.852651 | 0.728354 | 0.726592 | 0.039* | |
C4 | 0.5207 (5) | 0.8717 (4) | 0.68821 (18) | 0.0348 (5) | |
H4 | 0.545906 | 1.001606 | 0.724635 | 0.042* | |
C5 | 0.3009 (4) | 0.8470 (4) | 0.63443 (17) | 0.0349 (6) | |
H5 | 0.174797 | 0.958261 | 0.634589 | 0.042* | |
C6 | 0.2662 (4) | 0.6611 (4) | 0.58092 (16) | 0.0304 (5) | |
H6 | 0.114410 | 0.643651 | 0.544695 | 0.036* | |
C7 | 0.3908 (4) | 0.3082 (4) | 0.51888 (15) | 0.0270 (5) | |
H7 | 0.222390 | 0.270734 | 0.504648 | 0.032* | |
C8 | 0.4586 (4) | 0.0034 (4) | 0.42327 (14) | 0.0263 (5) | |
C9 | 0.2257 (4) | 0.0070 (4) | 0.37527 (15) | 0.0304 (5) | |
H9 | 0.116018 | 0.130115 | 0.380872 | 0.036* | |
C10 | 0.1571 (4) | −0.1720 (4) | 0.31930 (17) | 0.0340 (5) | |
H10 | −0.001169 | −0.171673 | 0.286384 | 0.041* | |
C11 | 0.3176 (5) | −0.3521 (4) | 0.31083 (16) | 0.0327 (5) | |
H11 | 0.269918 | −0.473587 | 0.271973 | 0.039* | |
C12 | 0.5480 (5) | −0.3533 (4) | 0.35956 (18) | 0.0324 (5) | |
H12 | 0.657396 | −0.477040 | 0.354374 | 0.039* | |
C13 | 0.6199 (4) | −0.1748 (4) | 0.41587 (16) | 0.0301 (5) | |
H13 | 0.778043 | −0.175337 | 0.448865 | 0.036* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0260 (9) | 0.0382 (9) | 0.0363 (9) | 0.0038 (6) | −0.0010 (7) | 0.0001 (7) |
O2 | 0.0137 (7) | 0.0461 (9) | 0.0418 (9) | −0.0015 (7) | 0.0047 (7) | −0.0028 (8) |
N1 | 0.0170 (9) | 0.0340 (9) | 0.0290 (10) | −0.0013 (7) | 0.0031 (7) | 0.0025 (8) |
C1 | 0.0253 (12) | 0.0287 (11) | 0.0250 (12) | −0.0010 (8) | 0.0073 (10) | 0.0032 (8) |
C2 | 0.0232 (12) | 0.0314 (11) | 0.0301 (12) | 0.0004 (8) | 0.0057 (10) | 0.0066 (9) |
C3 | 0.0308 (13) | 0.0359 (12) | 0.0320 (12) | −0.0082 (10) | 0.0059 (10) | −0.0024 (10) |
C4 | 0.0380 (14) | 0.0300 (11) | 0.0397 (13) | −0.0066 (9) | 0.0166 (11) | −0.0022 (10) |
C5 | 0.0346 (14) | 0.0328 (12) | 0.0403 (15) | 0.0032 (9) | 0.0150 (11) | 0.0065 (10) |
C6 | 0.0232 (11) | 0.0362 (12) | 0.0321 (12) | 0.0026 (9) | 0.0054 (9) | 0.0071 (10) |
C7 | 0.0185 (10) | 0.0327 (11) | 0.0293 (11) | 0.0009 (8) | 0.0028 (9) | 0.0049 (9) |
C8 | 0.0241 (11) | 0.0292 (11) | 0.0258 (13) | −0.0022 (8) | 0.0044 (10) | 0.0029 (8) |
C9 | 0.0218 (11) | 0.0379 (12) | 0.0316 (13) | 0.0017 (9) | 0.0053 (10) | −0.0012 (9) |
C10 | 0.0246 (11) | 0.0448 (13) | 0.0329 (12) | −0.0037 (9) | 0.0052 (10) | −0.0013 (11) |
C11 | 0.0328 (12) | 0.0340 (12) | 0.0328 (13) | −0.0066 (9) | 0.0096 (10) | −0.0021 (10) |
C12 | 0.0336 (12) | 0.0307 (11) | 0.0341 (12) | 0.0044 (9) | 0.0096 (10) | 0.0023 (10) |
C13 | 0.0249 (11) | 0.0350 (12) | 0.0307 (13) | 0.0025 (8) | 0.0056 (9) | 0.0053 (9) |
O1—C2 | 1.345 (3) | C5—H5 | 0.9500 |
O1—H1 | 0.9697 | C6—H6 | 0.9500 |
O2—N1 | 1.331 (2) | C7—H7 | 0.9500 |
N1—C7 | 1.302 (3) | C8—C13 | 1.382 (3) |
N1—C8 | 1.454 (3) | C8—C9 | 1.395 (3) |
C1—C2 | 1.407 (3) | C9—C10 | 1.386 (4) |
C1—C6 | 1.411 (3) | C9—H9 | 0.9500 |
C1—C7 | 1.453 (3) | C10—C11 | 1.391 (4) |
C2—C3 | 1.398 (4) | C10—H10 | 0.9500 |
C3—C4 | 1.377 (4) | C11—C12 | 1.389 (4) |
C3—H3 | 0.9500 | C11—H11 | 0.9500 |
C4—C5 | 1.385 (4) | C12—C13 | 1.390 (4) |
C4—H4 | 0.9500 | C12—H12 | 0.9500 |
C5—C6 | 1.372 (4) | C13—H13 | 0.9500 |
C2—O1—H1 | 105.1 | N1—C7—C1 | 126.9 (2) |
C7—N1—O2 | 122.78 (18) | N1—C7—H7 | 116.6 |
C7—N1—C8 | 121.79 (18) | C1—C7—H7 | 116.6 |
O2—N1—C8 | 115.43 (17) | C13—C8—C9 | 121.2 (2) |
C2—C1—C6 | 118.6 (2) | C13—C8—N1 | 117.2 (2) |
C2—C1—C7 | 125.97 (19) | C9—C8—N1 | 121.66 (19) |
C6—C1—C7 | 115.4 (2) | C10—C9—C8 | 118.9 (2) |
O1—C2—C3 | 118.3 (2) | C10—C9—H9 | 120.5 |
O1—C2—C1 | 122.5 (2) | C8—C9—H9 | 120.5 |
C3—C2—C1 | 119.1 (2) | C9—C10—C11 | 120.6 (2) |
C4—C3—C2 | 120.8 (2) | C9—C10—H10 | 119.7 |
C4—C3—H3 | 119.6 | C11—C10—H10 | 119.7 |
C2—C3—H3 | 119.6 | C12—C11—C10 | 119.6 (2) |
C3—C4—C5 | 120.5 (2) | C12—C11—H11 | 120.2 |
C3—C4—H4 | 119.7 | C10—C11—H11 | 120.2 |
C5—C4—H4 | 119.7 | C11—C12—C13 | 120.5 (2) |
C6—C5—C4 | 119.6 (2) | C11—C12—H12 | 119.8 |
C6—C5—H5 | 120.2 | C13—C12—H12 | 119.8 |
C4—C5—H5 | 120.2 | C8—C13—C12 | 119.2 (2) |
C5—C6—C1 | 121.2 (2) | C8—C13—H13 | 120.4 |
C5—C6—H6 | 119.4 | C12—C13—H13 | 120.4 |
C1—C6—H6 | 119.4 | ||
C6—C1—C2—O1 | 172.1 (2) | C6—C1—C7—N1 | 153.4 (2) |
C7—C1—C2—O1 | −4.2 (3) | C7—N1—C8—C13 | −153.0 (2) |
C6—C1—C2—C3 | −4.4 (3) | O2—N1—C8—C13 | 27.7 (3) |
C7—C1—C2—C3 | 179.3 (2) | C7—N1—C8—C9 | 27.3 (3) |
O1—C2—C3—C4 | −174.0 (2) | O2—N1—C8—C9 | −152.0 (2) |
C1—C2—C3—C4 | 2.6 (3) | C13—C8—C9—C10 | −0.1 (3) |
C2—C3—C4—C5 | 0.1 (4) | N1—C8—C9—C10 | 179.6 (2) |
C3—C4—C5—C6 | −1.0 (4) | C8—C9—C10—C11 | −0.2 (4) |
C4—C5—C6—C1 | −0.9 (4) | C9—C10—C11—C12 | 0.6 (4) |
C2—C1—C6—C5 | 3.6 (3) | C10—C11—C12—C13 | −0.7 (4) |
C7—C1—C6—C5 | −179.7 (2) | C9—C8—C13—C12 | 0.0 (3) |
O2—N1—C7—C1 | −0.4 (3) | N1—C8—C13—C12 | −179.8 (2) |
C8—N1—C7—C1 | −179.7 (2) | C11—C12—C13—C8 | 0.4 (4) |
C2—C1—C7—N1 | −30.2 (3) |
Cg1 and Cg2 are the centroids of the C1–C6 and C8–C13 aromatic rings, respectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O2 | 0.97 | 1.53 | 2.479 (2) | 167 |
C7—H7···O2i | 0.95 | 2.43 | 3.368 (3) | 167 |
C10—H10···O1ii | 0.95 | 2.53 | 3.227 (3) | 131 |
C11—H11···Cg1iii | 0.95 | 2.94 | 3.662 (3) | 136 |
C4—H4···Cg2iv | 0.95 | 2.77 | 3.545 (3) | 140 |
Symmetry codes: (i) x−1, y, z; (ii) x−1, −y, z−1/2; (iii) x, −y, z−1/2; (iv) x, −y+1, z+1/2. |
Contact | Distance | Symmetry operation |
O2···H7 | 2.43 | 1 + x, y, z |
O1···H10 | 2.53 | 1 + x, -y, 1/2 + z |
O2···H12 | 2.87 | x, 1 + y, z |
C3···H12 | 3.02 | x, -y, 1/2 + z |
H4···C11 | 2.86 | x, 1 - y, 1/2 + z |
H6···H13 | 2.46 | -1 + x, 1 + y, z |
Contact | Percentage contribution |
H···H | 44.1 |
C···H/H···C | 29.4 |
O···H/H···O | 17.3 |
C···C | 5.3 |
N···C/C···N | 1.7 |
N···H/H···N | 1.5 |
O···C/C···O | 0.7 |
Funding information
The support of NSF–MRI grant No. 1228232 for the purchase of the diffractometer and Tulane University for support of the Tulane Crystallography Laboratory are gratefully acknowledged.
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