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Z)-4-(4-hydroxybenzylidene)-3-methylisoxazol-5(4H)-one
and Hirshfeld surface analysis of (aLaboratoire de Cristallographie, Département de Physique, Université Mentouri-Constantine, 25000 Constantine, Algeria, and bLaboratoire de Synthèse de Molécules, d'Intérêts Biologiques, Département de Chimie, Université Mentouri-Constantine, 25000 Constantine, Algeria
*Correspondence e-mail: n_hamdouni@yahoo.fr
The title compound, C11H9NO3, contains an isoxazole and a hydroxybenzylidene ring, which are inclined to each another by 3.18 (8)°. There is an intramolecular C—H⋯O contact forming an S(7) ring. In the crystal, molecules stack head-to-tail in columns along the b-axis direction, linked by offset π–π interactions [intercentroid distances of 3.676 (1) and 3.723 (1) Å]. The columns are linked by O—H⋯O and O—H⋯N hydrogen bonds, forming layers parallel to the ab plane. The layers are linked by C—H⋯O hydrogen bonds, forming a supramolecular three-dimensional framework. An analysis of the Hirshfeld surfaces points to the importance of the O—H⋯O and O—H⋯N hydrogen bonding in the packing mechanism of the crystal structure.
Keywords: crystal structure; isoxazole; hydroxybenzylidene; Z configuration; hydrogen bonding; offset π–π interactions; Hirshfeld surface.
CCDC reference: 1845567
1. Chemical context
The isoxazole ring system is a component of many natural and medicinally active molecules that exhibit interesting biological activities (Wang et al., 2012). Isoxazole derivatives have been shown to possess anticonvulsant (Balalaie et al., 2000), antifungal (Santos et al., 2010), HDAC inhibitory (Conti et al., 2010), analgesic (Kano et al., 1967), antimicrobial (Padmaja et al., 2009), antituberculosis (Lee et al., 2009), antimycobacterial (Mao et al., 2010) and many other biological properties. They are also used for the treatment of leishmaniasis (Changtam et al., 2010) and for the treatment of patients with active arthritis (Suryawanshi et al., 2012). Furthermore, the isoxazole unit can be used as the basis for the design and construction of merocyanine dyes, which are used in optical recording and non-linear optical research (Zhang et al., 2011). In the present study, we report on the synthesis, and Hirshfeld surface analysis of the title isoxazole derivative.
2. Structural commentary
The molecular structure of the title compound is shown in Fig. 1. The molecule is composed of an isoxazole ring (O1/N1/C1–C3) that is almost coplanar with the benzene ring (C6–C11) of the 4-hydroxybenzylidene substituent; the two rings are inclined to each other by 3.18 (8)°. The configuration about the C2=C5 bond is Z, and within the molecule there is a short intramolecular C11—H11⋯O2 contact (Table 1), forming an S(7) ring motif. The bond lengths and bond angles agree well with those observed for a similar compound, the 2-hydroxybenzylidene analogue, (Z)-4-(2-hydroxybenzylidene)-3-methylisoxazol-5(4H)-one (Cheng et al., 2009). Here the hydroxyl group is in the ortho position, compared to the para position in the title compound.
3. Supramolecular features
In the crystal, molecules stack head-to-tail along the b-axis direction (Fig. 2), and are linked by offset π–π interactions: Cg1⋯Cg2iii,iv intercentroid distances are 3.676 (1) and 3.723 (1) Å, interplanar distances are 3.426 (1) and 3.489 (1) Å, slippages are 1.287 and 1.458 Å with the rings inclined to each other by 3.18 (8)°; symmetry codes: (iii) −x + , −y + , −z + 1; (iv) −x + , −y − , −z + 1. The molecular columns are linked by O—H⋯O and O—H⋯N hydrogen bonds (Table 1), forming layers parallel to (001). The layers are linked by C—H⋯O hydrogen bonds, forming a supramolecular three-dimensional framework (Table 1 and Fig. 2).
4. Analysis of the Hirshfeld surfaces
Additional insight into the intermolecular interactions was obtained from an analysis of the Hirshfeld surface (Spackman & Jayatilaka, 2009) and the two-dimensional fingerprint plots (McKinnon et al., 2007). The program CrystalExplorer (Turner et al., 2017) was used to generate Hirshfeld surfaces mapped over dnorm, de and the electrostatic potential for the title compound.
The analysis of the Hirshfeld surface mapped over dnorm is shown in Fig. 3. The O3—H3⋯O1i and O3—H3⋯N1i interactions between the corresponding donor and acceptor atoms are visualized as bright-red spots on both sides (zones 1 and 2) of the Hirshfeld surfaces (Fig. 4). Two other red spots exist, corresponding to the C5—H5⋯O2ii and C7—H7⋯Oii interactions (Fig. 4, zones 3 and 4); these are considered to be weak interactions by comparing them to the sum of the van der Waals radii. The donors and acceptors of intermolecular hydrogen bonds appear as blue and red regions, respectively, around the participating atoms on the Hirshfeld surface mapped over the calculated electrostatic potential (Fig. 5).
The overall two-dimensional fingerprint plot is illustrated in Fig. 6a, and the H⋯O/O⋯H, H⋯H, C⋯H/H⋯C, and N⋯H/H⋯N contacts are illustrated in Fig. 6b–f, respectively. The H⋯O/O⋯H contacts (Fig. 6b) account for 33.9% of the Hirshfeld surface, representing the largest contribution and is displayed on the fingerprint plots by a pair of short spikes at de + di = 2.3 Å. This distance is ca 0.5 Å shorter than the sum of the van der Waals radii of the individual atoms, which means it is a very strong interaction. A contribution of 31.0% was found for the interatomic H⋯H contacts (Fig. 6c), with a distinctive peak in the fingerprint plot at de + di = 2.2 Å; the van der Waals radius for this interaction is 2.4 Å. The H⋯C/C⋯H contacts (9.6% contribution; Fig. 6d) are indicated by a pair of short peaks at de + di = 2.7 Å, equal to the sum of the van der Waals radii. The H⋯N/N⋯H contacts (Fig. 6e), which account for only 8.4% of the Hirshfeld surface, are displayed on the fingerprint plot as a pair of long spikes at de + di = 2.0 Å. This distance differs by ca 0.7 Å from the sum of the van der Waals radii, which means it is the strongest interaction present. The C⋯C contacts (Fig. 6f), which account for 11.7% of the Hirshfeld surface with de + di = 3.4 Å, indicate the presence of π–π stacking.
5. Database survey
A search of the Cambridge Structural Database (CSD, V3.59, last update February 2018; Groom et al., 2016) for 4-substituted 3-methyl-isoxzol-5(4H)-ones gave 22 hits. Of these, six compounds involve a benzylidene substituent. The configuration about the C=C bond is Z in all six compounds and the benzene ring is inclined to the isoxazole ring by angles as small as 1.14° in (Z)-4-benzylidene-3-methylisoxazol-5(4H)-one (MBYIOZ01; Chandra et al., 2012) compared to ca 11.59° in (Z)-4-(4-methoxybenzylidene)-3-methyl-1,2-oxazol-5(4H)-one (YIMWIC; Saikh et al., 2013). The most relevant structure is the 2-hydroxybenzylidene analogue, viz. (Z)-4-(2-hydroxybenzylidene)-3-methylisoxazol-5(4H)-one (AJESAK; Cheng et al., 2009), in which the two rings are inclined to each other by ca 6.53°, compared to 3.18 (8)° in the title compound. The Z configuration of all six molecules indicates that there is an intramolecular C—H⋯O contact present forming an S(7) ring motif, as in the title compound (Fig. 1 and Table 1).
6. Synthesis and crystallization
4-Hydroxybenzaldehyde (1 mmol), hydroxylamine hydrochloride (1 mmol), ethylacetoacetate (1 mmol) and K2CO3 (5 ml) were mixed in a 25 ml flask equipped with a magnetic stirrer. The mixture was refluxed in 5 ml of water for 1 h (the reaction was monitored by TLC). On completion of the reaction, the mixture was gradually poured into ice-cold water. Stirring was maintained for a few minutes and the obtained solid was filtered and purified by crystallization from ethanol (yield 83%), yielding pale-yellow needle-like crystals on slow evaporation of the solvent.
7. Refinement
Crystal data, data collection and structure . The hydroxyl H atom was located in a difference-Fourier map and freely refined. The C-bound H atoms were included in calculated positions and treated as riding: C—H = 0.93–0.96 Å with Uiso(H) = 1.5Ueq(C-methyl) and 1.2Ueq(C) for other H atoms.
details are summarized in Table 2Supporting information
CCDC reference: 1845567
https://doi.org/10.1107/S2056989018007867/zp2027sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989018007867/zp2027Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989018007867/zp2027Isup3.cml
Data collection: CrysAlis PRO (Agilent, 2013); cell
CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2018/3 (Sheldrick, 2015), PLATON (Spek, 2009) and publCIF (Westrip, 2010).C11H9NO3 | F(000) = 848 |
Mr = 203.19 | Dx = 1.400 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
a = 21.191 (2) Å | Cell parameters from 1714 reflections |
b = 7.2352 (11) Å | θ = 4.1–32° |
c = 12.9569 (14) Å | µ = 0.10 mm−1 |
β = 103.920 (11)° | T = 293 K |
V = 1928.2 (4) Å3 | Needle, pale yellow |
Z = 8 | 0.36 × 0.23 × 0.11 mm |
Agilent Technologies Xcalibur, Eos diffractometer | 1891 independent reflections |
Radiation source: Enhance (Mo) X-ray Source | 1465 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.021 |
ω scans | θmax = 26.0°, θmin = 3.2° |
Absorption correction: multi-scan (CrysalisPro; Agilent, 2013) | h = −26→23 |
Tmin = 0.551, Tmax = 1.000 | k = −8→8 |
4536 measured reflections | l = −15→12 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: mixed |
R[F2 > 2σ(F2)] = 0.040 | H atoms treated by a mixture of independent and constrained refinement |
wR(F2) = 0.113 | w = 1/[σ2(Fo2) + (0.0595P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.04 | (Δ/σ)max = 0.001 |
1891 reflections | Δρmax = 0.19 e Å−3 |
142 parameters | Δρmin = −0.13 e Å−3 |
0 restraints | Extinction correction: (SHELXL-2018/3; Sheldrick, 2015), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0020 (6) |
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 | 0.62276 (5) | 0.14571 (16) | 0.60644 (8) | 0.0492 (4) | |
O2 | 0.72284 (6) | 0.0722 (2) | 0.69282 (8) | 0.0626 (4) | |
O3 | 0.99352 (6) | −0.2162 (2) | 0.60528 (10) | 0.0613 (4) | |
H3O | 1.0132 (11) | −0.237 (3) | 0.5558 (16) | 0.092 (8)* | |
N1 | 0.58554 (6) | 0.16143 (18) | 0.49783 (10) | 0.0448 (4) | |
C1 | 0.68443 (8) | 0.0886 (2) | 0.60805 (12) | 0.0392 (4) | |
C2 | 0.68735 (7) | 0.06174 (19) | 0.49745 (11) | 0.0308 (3) | |
C3 | 0.62309 (7) | 0.11381 (19) | 0.43784 (12) | 0.0347 (4) | |
C4 | 0.59837 (9) | 0.1192 (2) | 0.32016 (13) | 0.0521 (5) | |
H4A | 0.558271 | 0.187052 | 0.302307 | 0.078* | |
H4B | 0.591061 | −0.004561 | 0.293277 | 0.078* | |
H4C | 0.629819 | 0.178707 | 0.289026 | 0.078* | |
C5 | 0.73584 (7) | 0.00370 (18) | 0.45337 (10) | 0.0321 (4) | |
H5 | 0.723867 | 0.000592 | 0.379466 | 0.039* | |
C6 | 0.80178 (7) | −0.05397 (19) | 0.49675 (11) | 0.0309 (3) | |
C7 | 0.83942 (7) | −0.0968 (2) | 0.42463 (11) | 0.0374 (4) | |
H7 | 0.820742 | −0.088293 | 0.352088 | 0.045* | |
C8 | 0.90318 (8) | −0.1508 (2) | 0.45834 (12) | 0.0407 (4) | |
H8 | 0.927260 | −0.178127 | 0.409006 | 0.049* | |
C9 | 0.93153 (7) | −0.1646 (2) | 0.56651 (13) | 0.0391 (4) | |
C10 | 0.89502 (8) | −0.1264 (2) | 0.63930 (12) | 0.0414 (4) | |
H10 | 0.913860 | −0.136911 | 0.711693 | 0.050* | |
C11 | 0.83143 (7) | −0.0732 (2) | 0.60553 (11) | 0.0374 (4) | |
H11 | 0.807415 | −0.049326 | 0.655426 | 0.045* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0342 (7) | 0.0808 (8) | 0.0351 (6) | 0.0182 (6) | 0.0132 (5) | 0.0031 (5) |
O2 | 0.0413 (7) | 0.1180 (11) | 0.0271 (6) | 0.0283 (7) | 0.0056 (5) | −0.0015 (6) |
O3 | 0.0259 (6) | 0.1075 (11) | 0.0490 (8) | 0.0214 (6) | 0.0061 (6) | −0.0077 (7) |
N1 | 0.0290 (8) | 0.0631 (8) | 0.0410 (8) | 0.0122 (7) | 0.0057 (6) | 0.0029 (6) |
C1 | 0.0271 (8) | 0.0580 (9) | 0.0335 (8) | 0.0104 (7) | 0.0091 (7) | 0.0017 (7) |
C2 | 0.0256 (8) | 0.0372 (7) | 0.0289 (7) | 0.0031 (6) | 0.0050 (6) | 0.0010 (6) |
C3 | 0.0274 (8) | 0.0405 (7) | 0.0363 (8) | 0.0049 (7) | 0.0076 (7) | 0.0005 (6) |
C4 | 0.0392 (10) | 0.0710 (11) | 0.0397 (9) | 0.0134 (9) | −0.0027 (8) | −0.0004 (8) |
C5 | 0.0294 (8) | 0.0403 (7) | 0.0263 (7) | 0.0033 (6) | 0.0061 (6) | −0.0002 (6) |
C6 | 0.0258 (8) | 0.0373 (7) | 0.0297 (7) | 0.0036 (6) | 0.0067 (6) | −0.0021 (6) |
C7 | 0.0324 (9) | 0.0516 (9) | 0.0283 (7) | 0.0051 (7) | 0.0075 (6) | −0.0001 (6) |
C8 | 0.0297 (9) | 0.0582 (9) | 0.0374 (8) | 0.0057 (7) | 0.0141 (7) | −0.0051 (7) |
C9 | 0.0225 (8) | 0.0503 (9) | 0.0435 (8) | 0.0067 (7) | 0.0062 (7) | −0.0045 (7) |
C10 | 0.0323 (9) | 0.0588 (9) | 0.0304 (8) | 0.0081 (7) | 0.0025 (7) | −0.0033 (7) |
C11 | 0.0292 (8) | 0.0531 (9) | 0.0310 (8) | 0.0083 (7) | 0.0093 (6) | −0.0032 (6) |
O1—C1 | 1.3660 (19) | C5—C6 | 1.4370 (19) |
O1—N1 | 1.4426 (15) | C5—H5 | 0.9300 |
O2—C1 | 1.2054 (18) | C6—C7 | 1.401 (2) |
O3—C9 | 1.3417 (18) | C6—C11 | 1.4053 (19) |
O3—H3O | 0.86 (2) | C7—C8 | 1.373 (2) |
N1—C3 | 1.2860 (19) | C7—H7 | 0.9300 |
C1—C2 | 1.462 (2) | C8—C9 | 1.389 (2) |
C2—C5 | 1.357 (2) | C8—H8 | 0.9300 |
C2—C3 | 1.445 (2) | C9—C10 | 1.384 (2) |
C3—C4 | 1.489 (2) | C10—C11 | 1.368 (2) |
C4—H4A | 0.9600 | C10—H10 | 0.9300 |
C4—H4B | 0.9600 | C11—H11 | 0.9300 |
C4—H4C | 0.9600 | ||
C1—O1—N1 | 109.59 (11) | C6—C5—H5 | 113.2 |
C9—O3—H3O | 112.2 (14) | C7—C6—C11 | 117.27 (13) |
C3—N1—O1 | 107.22 (11) | C7—C6—C5 | 117.34 (13) |
O2—C1—O1 | 118.53 (14) | C11—C6—C5 | 125.39 (13) |
O2—C1—C2 | 134.54 (15) | C8—C7—C6 | 121.68 (13) |
O1—C1—C2 | 106.93 (12) | C8—C7—H7 | 119.2 |
C5—C2—C3 | 124.58 (13) | C6—C7—H7 | 119.2 |
C5—C2—C1 | 131.96 (13) | C7—C8—C9 | 119.66 (14) |
C3—C2—C1 | 103.46 (13) | C7—C8—H8 | 120.2 |
N1—C3—C2 | 112.79 (13) | C9—C8—H8 | 120.2 |
N1—C3—C4 | 119.70 (14) | O3—C9—C10 | 117.26 (14) |
C2—C3—C4 | 127.50 (14) | O3—C9—C8 | 122.99 (14) |
C3—C4—H4A | 109.5 | C10—C9—C8 | 119.75 (14) |
C3—C4—H4B | 109.5 | C11—C10—C9 | 120.49 (14) |
H4A—C4—H4B | 109.5 | C11—C10—H10 | 119.8 |
C3—C4—H4C | 109.5 | C9—C10—H10 | 119.8 |
H4A—C4—H4C | 109.5 | C10—C11—C6 | 121.12 (14) |
H4B—C4—H4C | 109.5 | C10—C11—H11 | 119.4 |
C2—C5—C6 | 133.54 (13) | C6—C11—H11 | 119.4 |
C2—C5—H5 | 113.2 | ||
C1—O1—N1—C3 | 0.71 (16) | C1—C2—C5—C6 | 0.4 (3) |
N1—O1—C1—O2 | 178.29 (14) | C2—C5—C6—C7 | −176.83 (15) |
N1—O1—C1—C2 | −1.37 (16) | C2—C5—C6—C11 | 4.0 (3) |
O2—C1—C2—C5 | 1.7 (3) | C11—C6—C7—C8 | −1.6 (2) |
O1—C1—C2—C5 | −178.74 (15) | C5—C6—C7—C8 | 179.15 (14) |
O2—C1—C2—C3 | −178.13 (19) | C6—C7—C8—C9 | 0.2 (2) |
O1—C1—C2—C3 | 1.45 (16) | C7—C8—C9—O3 | −179.90 (15) |
O1—N1—C3—C2 | 0.28 (17) | C7—C8—C9—C10 | 1.0 (2) |
O1—N1—C3—C4 | −178.93 (13) | O3—C9—C10—C11 | −179.90 (14) |
C5—C2—C3—N1 | 179.09 (14) | C8—C9—C10—C11 | −0.7 (2) |
C1—C2—C3—N1 | −1.08 (17) | C9—C10—C11—C6 | −0.7 (2) |
C5—C2—C3—C4 | −1.8 (2) | C7—C6—C11—C10 | 1.8 (2) |
C1—C2—C3—C4 | 178.06 (14) | C5—C6—C11—C10 | −178.97 (14) |
C3—C2—C5—C6 | −179.81 (14) |
D—H···A | D—H | H···A | D···A | D—H···A |
C11—H11···O2 | 0.93 | 2.15 | 2.989 (2) | 149 |
O3—H3O···O1i | 0.86 (2) | 2.41 (2) | 2.9119 (18) | 118 (2) |
O3—H3O···N1i | 0.86 (2) | 2.00 (2) | 2.7984 (19) | 154 (2) |
C5—H5···O2ii | 0.93 | 2.47 | 3.3655 (17) | 162 |
C7—H7···O2ii | 0.93 | 2.55 | 3.4038 (19) | 152 |
Symmetry codes: (i) x+1/2, y−1/2, z; (ii) x, −y, z−1/2. |
Acknowledgements
We thank Mr F. Saidi, Engineer at the Laboratory of Crystallography, University Constantine 1, for assistance with the data collection.
Funding information
This work was supported by the Laboratoire de Cristallographie, Departement de Physique, Université Constantine 1, Algeria.
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