organic compounds
2-(4-Chloro-2-nitrophenyl)-5-[4-(propyloxy)phenyl]-1,3,4-oxadiazole
aUniversity of Mainz, Institut for Organic Chemistry, Duesbergweg 10-14, 55099 Mainz, Germany
*Correspondence e-mail: detert@uni-mainz.de
The title compound, C17H14ClN3O4, was prepared by the Huisgen reaction of 4-chloro-2-nitrobenzoyl chloride and 5-(4-propyloxyphenyl)tetrazole. The diphenyl-1,3,4-oxadiazole unit is nearly planar. The oxadiazole ring is inclined to the 4-chloro-2-nitrophenyl ring by 7.77 (8)°, and by 7.93 (8)° to the 4-propyloxyphenyl ring. The benzene rings are inclined to one another by 1.32 (7)°. The nitro group is twisted out of the plane of the benzene ring to which it is attached by 73.59 (16)°. The propoxy chain mean plane is inclined to the benzene ring to which it is attached by 4.46 (13)°. In the crystal, C—H⋯O and C—H⋯N hydrogen bonds connect the molecules, forming ribbons propagating along the b-axis direction. The ribbons are linked by C—H⋯π interactions, forming slabs parallel to the ab plane.
Keywords: crystal structure; 1,3,4-oxadiazole; nitro compound; hydrogen bonding; C—H⋯π interactions.
CCDC reference: 1515447
Structure description
Donor–acceptor substituted π-systems are solvatochromic (Detert et al. 2002; Rettig 1986), making these materials interesting for sensing and non-linear optical applications (Schmitt et al. 2008; Schönhaber et al. 2010; Franco et al. 2010). o-Nitrobiaryl compounds are starting materials for the Cadogan (Cadogan 1962; Letessier et al. 2013).
Apart from the nitro group, te title compound, Fig. 1, is nearly planar. The oxadiazole ring (O8/N10/N11/C7/C9) is inclined to the benzene ring (C1–C6) by 7.77 (8)° and by 7.93 (8)° to benzene ring (C12–C17). The benzene rings are inclined to one another by 1.32 (7)°. The nitro group is twisted out of the plane of the benzene ring (C1–C6), to which it is attached, by 73.59 (16)%. The propoxy chain mean plane (O18/C19–C21) is inclined to the benzene ring (C12–C17), to which it is attached, by 4.46 (13)°. The torsion angles along the biaryl axes are −7.5 (2)° (C6—C1—C7—N11) and 7.7 (2)° (N10—C9—C12—C17). The bonds connecting the central 1,3,4-oxadiazole ring with the donor- and acceptor-substituted benzene rings, 1.4555 (17) and 1.4527 (17) Å, respectively, are very similar. The C4—Cl1 bond length of 1.7270 (14) Å is nearly identical to the bond lengths [1.727, 1.728 Å] found in 1-chloro-3,4-dinitrobenzene (Wilkins & Small, 1985).
In the crystal, molecules are connected via C—H⋯O and C—H⋯N hydrogen bonds, involving the aromatic rings to the the nitro and oxadiazole groups, respectively, forming ribbons that propagate along the b-axis direction (Table 1 and Fig. 2). The ribbons are linked by C—H⋯π interactions, forming slabs parallel to the ab plane (Table 1 and Fig. 3).
Synthesis and crystallization
4-Chloro-2-nitrobenzoic acid (640 mg, 3.18 mmol) was refluxed for 12 h in thionyl chloride (6 ml, 82.7 mmol), excess thionyl chloride was distilled off in vacuo and the crude benzoyl chloride was dissolved in toluene (15 ml), then 5-(4-propyloxyphenyl)tetrazole (466 mg, 2.28 mmol) and 2,4,6-collidine (0.6 ml, 4.53 mmol) were added. After refluxing for 72 h, the mixture was cooled and 2N HCl(aq) (25 ml) was added. The aqueous phase was extracted with chloroform (3 × 20 ml). The combined organic phase was dried with MgSO4 followed by evaporation and (silica gel, toluene: ethyl acetate = 40:1) to afforded 723 mg of the title compound (yield 88%). 1H NMR (CDCl3) δ 8.07 (d, J = 8.4 Hz, 1H), 7.98–7.95 (m, 3H), 7.75 (dd, J = 8.4, 2.1 Hz, 1H), 7.02 – 6.99 (m, 2H), 4.00 (t, J = 6.5 Hz, 2H), 1.89–1.80 (m, 2H), 1.06 (t, J = 7.4 Hz, 3H). 13C NMR (CDCl3) δ 166.1, 162.6, 160.0, 138.6, 133.2, 132.5, 129.1, 125.0, 117.1, 115.4, 115.3, 8.16, 69.9, 22.6, 10.6. The title compound was crystallized from a dichloromethane solution giving colourless plate-like crystals (m.p. 419–411 K).
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2Structural data
CCDC reference: 1515447
https://doi.org/10.1107/S241431461601782X/su4093sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S241431461601782X/su4093Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S241431461601782X/su4093Isup3.cml
Data collection: X-AREA (Stoe & Cie, 1996); cell
X-AREA (Stoe & Cie, 1996); data reduction: X-RED32 (Stoe & Cie, 1996); program(s) used to solve structure: SHELXT2014 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2009) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL2014 (Sheldrick, 2015b) and PLATON (Spek, 2009).C17H14ClN3O4 | Z = 2 |
Mr = 359.76 | F(000) = 372 |
Triclinic, P1 | Dx = 1.461 Mg m−3 |
a = 7.5691 (5) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.7907 (5) Å | Cell parameters from 8906 reflections |
c = 14.904 (1) Å | θ = 2.8–28.2° |
α = 101.911 (5)° | µ = 0.26 mm−1 |
β = 91.311 (5)° | T = 193 K |
γ = 107.224 (5)° | Plate, colourless |
V = 818.06 (10) Å3 | 0.44 × 0.28 × 0.08 mm |
STOE IPDS 2T diffractometer | Rint = 0.018 |
Detector resolution: 6.67 pixels mm-1 | θmax = 28.1°, θmin = 2.8° |
rotation method scans | h = −8→10 |
7659 measured reflections | k = −10→10 |
3942 independent reflections | l = −19→19 |
3221 reflections with I > 2σ(I) |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.098 | H-atom parameters constrained |
S = 1.04 | w = 1/[σ2(Fo2) + (0.0509P)2 + 0.2041P] where P = (Fo2 + 2Fc2)/3 |
3942 reflections | (Δ/σ)max = 0.001 |
227 parameters | Δρmax = 0.35 e Å−3 |
0 restraints | Δρmin = −0.38 e Å−3 |
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 | ||
Cl1 | 0.99714 (6) | 1.19481 (5) | 0.78094 (3) | 0.04350 (12) | |
C1 | 0.74265 (17) | 0.98285 (17) | 0.48656 (9) | 0.0236 (2) | |
C2 | 0.76872 (19) | 0.86300 (17) | 0.53984 (9) | 0.0266 (3) | |
H2 | 0.7314 | 0.7343 | 0.5137 | 0.032* | |
C3 | 0.84763 (19) | 0.92731 (19) | 0.62969 (9) | 0.0290 (3) | |
H3 | 0.8658 | 0.8438 | 0.6646 | 0.035* | |
C4 | 0.90006 (19) | 1.11479 (19) | 0.66840 (9) | 0.0284 (3) | |
C5 | 0.87652 (19) | 1.23889 (18) | 0.61822 (9) | 0.0293 (3) | |
H5 | 0.9124 | 1.3673 | 0.6449 | 0.035* | |
C6 | 0.79957 (18) | 1.17076 (17) | 0.52846 (9) | 0.0251 (3) | |
C7 | 0.65423 (18) | 0.91012 (17) | 0.39304 (9) | 0.0244 (3) | |
O8 | 0.61819 (13) | 0.72641 (12) | 0.35657 (6) | 0.0254 (2) | |
C9 | 0.53202 (18) | 0.70529 (17) | 0.27188 (9) | 0.0247 (3) | |
N10 | 0.51751 (18) | 0.85882 (16) | 0.25766 (8) | 0.0330 (3) | |
N11 | 0.59744 (18) | 0.99363 (16) | 0.33768 (8) | 0.0328 (3) | |
C12 | 0.46798 (18) | 0.52310 (17) | 0.21119 (9) | 0.0249 (3) | |
C13 | 0.47390 (18) | 0.36665 (18) | 0.24229 (9) | 0.0261 (3) | |
H13 | 0.5218 | 0.3791 | 0.3036 | 0.031* | |
C14 | 0.41008 (19) | 0.19464 (18) | 0.18386 (9) | 0.0272 (3) | |
H14 | 0.4129 | 0.0887 | 0.2053 | 0.033* | |
C15 | 0.34137 (19) | 0.17554 (18) | 0.09339 (9) | 0.0264 (3) | |
C16 | 0.33658 (19) | 0.33078 (18) | 0.06153 (9) | 0.0281 (3) | |
H16 | 0.2917 | 0.3185 | −0.0003 | 0.034* | |
C17 | 0.39800 (19) | 0.50300 (18) | 0.12099 (9) | 0.0284 (3) | |
H17 | 0.3923 | 0.6086 | 0.1000 | 0.034* | |
O18 | 0.28345 (15) | 0.00031 (13) | 0.04241 (7) | 0.0329 (2) | |
C19 | 0.2206 (2) | −0.03094 (19) | −0.05283 (9) | 0.0302 (3) | |
H19A | 0.3227 | 0.0304 | −0.0868 | 0.036* | |
H19B | 0.1163 | 0.0193 | −0.0590 | 0.036* | |
C20 | 0.1582 (2) | −0.23635 (19) | −0.09084 (10) | 0.0306 (3) | |
H20A | 0.0605 | −0.2966 | −0.0544 | 0.037* | |
H20B | 0.2643 | −0.2845 | −0.0855 | 0.037* | |
C21 | 0.0825 (2) | −0.2826 (2) | −0.19156 (10) | 0.0399 (4) | |
H21A | 0.1759 | −0.2153 | −0.2267 | 0.060* | |
H21B | −0.0304 | −0.2466 | −0.1961 | 0.060* | |
H21C | 0.0534 | −0.4154 | −0.2166 | 0.060* | |
N22 | 0.78583 (16) | 1.30994 (15) | 0.47701 (8) | 0.0285 (2) | |
O23 | 0.89671 (16) | 1.34446 (14) | 0.42036 (7) | 0.0382 (3) | |
O24 | 0.66822 (17) | 1.38593 (16) | 0.49721 (9) | 0.0472 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cl1 | 0.0577 (3) | 0.0393 (2) | 0.02601 (18) | 0.00562 (17) | −0.01008 (15) | 0.00578 (14) |
C1 | 0.0236 (6) | 0.0223 (6) | 0.0239 (6) | 0.0054 (5) | 0.0023 (5) | 0.0054 (5) |
C2 | 0.0300 (6) | 0.0216 (6) | 0.0277 (6) | 0.0069 (5) | 0.0025 (5) | 0.0059 (5) |
C3 | 0.0327 (7) | 0.0289 (6) | 0.0271 (6) | 0.0090 (5) | 0.0029 (5) | 0.0110 (5) |
C4 | 0.0314 (7) | 0.0295 (7) | 0.0212 (6) | 0.0056 (5) | −0.0001 (5) | 0.0044 (5) |
C5 | 0.0342 (7) | 0.0227 (6) | 0.0264 (6) | 0.0036 (5) | 0.0006 (5) | 0.0035 (5) |
C6 | 0.0267 (6) | 0.0220 (6) | 0.0259 (6) | 0.0052 (5) | 0.0026 (5) | 0.0075 (5) |
C7 | 0.0256 (6) | 0.0196 (5) | 0.0264 (6) | 0.0052 (5) | 0.0022 (5) | 0.0044 (5) |
O8 | 0.0323 (5) | 0.0207 (4) | 0.0219 (4) | 0.0071 (3) | −0.0015 (4) | 0.0037 (3) |
C9 | 0.0257 (6) | 0.0259 (6) | 0.0216 (6) | 0.0065 (5) | −0.0009 (5) | 0.0059 (5) |
N10 | 0.0424 (7) | 0.0242 (5) | 0.0299 (6) | 0.0090 (5) | −0.0093 (5) | 0.0036 (4) |
N11 | 0.0410 (7) | 0.0243 (5) | 0.0306 (6) | 0.0086 (5) | −0.0076 (5) | 0.0037 (5) |
C12 | 0.0261 (6) | 0.0241 (6) | 0.0231 (6) | 0.0060 (5) | 0.0007 (5) | 0.0051 (5) |
C13 | 0.0303 (6) | 0.0272 (6) | 0.0206 (6) | 0.0086 (5) | −0.0024 (5) | 0.0055 (5) |
C14 | 0.0327 (7) | 0.0251 (6) | 0.0247 (6) | 0.0096 (5) | −0.0004 (5) | 0.0069 (5) |
C15 | 0.0281 (6) | 0.0264 (6) | 0.0228 (6) | 0.0073 (5) | 0.0009 (5) | 0.0034 (5) |
C16 | 0.0324 (7) | 0.0309 (7) | 0.0196 (6) | 0.0073 (5) | −0.0020 (5) | 0.0068 (5) |
C17 | 0.0331 (7) | 0.0266 (6) | 0.0256 (6) | 0.0070 (5) | −0.0003 (5) | 0.0097 (5) |
O18 | 0.0459 (6) | 0.0260 (5) | 0.0229 (5) | 0.0082 (4) | −0.0053 (4) | 0.0018 (4) |
C19 | 0.0355 (7) | 0.0306 (7) | 0.0218 (6) | 0.0083 (5) | −0.0010 (5) | 0.0028 (5) |
C20 | 0.0320 (7) | 0.0288 (6) | 0.0268 (6) | 0.0065 (5) | −0.0024 (5) | 0.0018 (5) |
C21 | 0.0479 (9) | 0.0358 (8) | 0.0290 (7) | 0.0100 (7) | −0.0071 (6) | −0.0029 (6) |
N22 | 0.0340 (6) | 0.0206 (5) | 0.0279 (6) | 0.0041 (4) | −0.0025 (5) | 0.0056 (4) |
O23 | 0.0511 (6) | 0.0310 (5) | 0.0313 (5) | 0.0067 (5) | 0.0074 (5) | 0.0125 (4) |
O24 | 0.0483 (7) | 0.0397 (6) | 0.0648 (8) | 0.0234 (5) | 0.0108 (6) | 0.0214 (6) |
Cl1—C4 | 1.7270 (14) | C13—H13 | 0.9500 |
C1—C2 | 1.3961 (18) | C14—C15 | 1.3964 (18) |
C1—C6 | 1.3984 (17) | C14—H14 | 0.9500 |
C1—C7 | 1.4555 (17) | C15—O18 | 1.3548 (16) |
C2—C3 | 1.3822 (19) | C15—C16 | 1.3970 (19) |
C2—H2 | 0.9500 | C16—C17 | 1.3867 (18) |
C3—C4 | 1.3864 (19) | C16—H16 | 0.9500 |
C3—H3 | 0.9500 | C17—H17 | 0.9500 |
C4—C5 | 1.3857 (19) | O18—C19 | 1.4346 (16) |
C5—C6 | 1.3779 (18) | C19—C20 | 1.5069 (18) |
C5—H5 | 0.9500 | C19—H19A | 0.9900 |
C6—N22 | 1.4768 (16) | C19—H19B | 0.9900 |
C7—N11 | 1.2883 (17) | C20—C21 | 1.5253 (19) |
C7—O8 | 1.3635 (14) | C20—H20A | 0.9900 |
O8—C9 | 1.3633 (15) | C20—H20B | 0.9900 |
C9—N10 | 1.2920 (17) | C21—H21A | 0.9800 |
C9—C12 | 1.4527 (17) | C21—H21B | 0.9800 |
N10—N11 | 1.4019 (16) | C21—H21C | 0.9800 |
C12—C17 | 1.3941 (18) | N22—O23 | 1.2173 (16) |
C12—C13 | 1.4026 (17) | N22—O24 | 1.2183 (17) |
C13—C14 | 1.3796 (18) | ||
C2—C1—C6 | 116.88 (12) | C13—C14—H14 | 119.8 |
C2—C1—C7 | 120.09 (11) | C15—C14—H14 | 119.8 |
C6—C1—C7 | 123.00 (11) | O18—C15—C14 | 115.03 (12) |
C3—C2—C1 | 121.50 (12) | O18—C15—C16 | 124.85 (12) |
C3—C2—H2 | 119.2 | C14—C15—C16 | 120.13 (12) |
C1—C2—H2 | 119.2 | C17—C16—C15 | 119.33 (12) |
C2—C3—C4 | 119.40 (12) | C17—C16—H16 | 120.3 |
C2—C3—H3 | 120.3 | C15—C16—H16 | 120.3 |
C4—C3—H3 | 120.3 | C16—C17—C12 | 120.80 (12) |
C5—C4—C3 | 121.12 (12) | C16—C17—H17 | 119.6 |
C5—C4—Cl1 | 119.52 (10) | C12—C17—H17 | 119.6 |
C3—C4—Cl1 | 119.36 (11) | C15—O18—C19 | 118.75 (11) |
C6—C5—C4 | 118.10 (12) | O18—C19—C20 | 107.23 (11) |
C6—C5—H5 | 120.9 | O18—C19—H19A | 110.3 |
C4—C5—H5 | 120.9 | C20—C19—H19A | 110.3 |
C5—C6—C1 | 122.98 (12) | O18—C19—H19B | 110.3 |
C5—C6—N22 | 115.73 (11) | C20—C19—H19B | 110.3 |
C1—C6—N22 | 121.25 (11) | H19A—C19—H19B | 108.5 |
N11—C7—O8 | 112.64 (11) | C19—C20—C21 | 110.74 (12) |
N11—C7—C1 | 129.40 (12) | C19—C20—H20A | 109.5 |
O8—C7—C1 | 117.93 (11) | C21—C20—H20A | 109.5 |
C9—O8—C7 | 102.51 (10) | C19—C20—H20B | 109.5 |
N10—C9—O8 | 112.22 (11) | C21—C20—H20B | 109.5 |
N10—C9—C12 | 128.58 (12) | H20A—C20—H20B | 108.1 |
O8—C9—C12 | 119.19 (11) | C20—C21—H21A | 109.5 |
C9—N10—N11 | 106.49 (11) | C20—C21—H21B | 109.5 |
C7—N11—N10 | 106.13 (11) | H21A—C21—H21B | 109.5 |
C17—C12—C13 | 119.45 (12) | C20—C21—H21C | 109.5 |
C17—C12—C9 | 119.63 (12) | H21A—C21—H21C | 109.5 |
C13—C12—C9 | 120.92 (11) | H21B—C21—H21C | 109.5 |
C14—C13—C12 | 119.97 (12) | O23—N22—O24 | 125.20 (12) |
C14—C13—H13 | 120.0 | O23—N22—C6 | 117.67 (11) |
C12—C13—H13 | 120.0 | O24—N22—C6 | 117.08 (12) |
C13—C14—C15 | 120.31 (12) | ||
C6—C1—C2—C3 | −0.19 (19) | C1—C7—N11—N10 | −178.06 (13) |
C7—C1—C2—C3 | −178.23 (13) | C9—N10—N11—C7 | 0.37 (16) |
C1—C2—C3—C4 | 0.8 (2) | N10—C9—C12—C17 | 7.7 (2) |
C2—C3—C4—C5 | −0.7 (2) | O8—C9—C12—C17 | −173.09 (12) |
C2—C3—C4—Cl1 | 179.54 (11) | N10—C9—C12—C13 | −171.67 (14) |
C3—C4—C5—C6 | −0.1 (2) | O8—C9—C12—C13 | 7.51 (19) |
Cl1—C4—C5—C6 | 179.66 (11) | C17—C12—C13—C14 | −0.3 (2) |
C4—C5—C6—C1 | 0.8 (2) | C9—C12—C13—C14 | 179.14 (12) |
C4—C5—C6—N22 | −177.27 (12) | C12—C13—C14—C15 | 0.7 (2) |
C2—C1—C6—C5 | −0.6 (2) | C13—C14—C15—O18 | 179.73 (12) |
C7—C1—C6—C5 | 177.33 (13) | C13—C14—C15—C16 | −0.1 (2) |
C2—C1—C6—N22 | 177.30 (12) | O18—C15—C16—C17 | 179.22 (13) |
C7—C1—C6—N22 | −4.7 (2) | C14—C15—C16—C17 | −1.0 (2) |
C2—C1—C7—N11 | 170.45 (14) | C15—C16—C17—C12 | 1.4 (2) |
C6—C1—C7—N11 | −7.5 (2) | C13—C12—C17—C16 | −0.8 (2) |
C2—C1—C7—O8 | −7.31 (18) | C9—C12—C17—C16 | 179.77 (13) |
C6—C1—C7—O8 | 174.78 (11) | C14—C15—O18—C19 | −176.50 (12) |
N11—C7—O8—C9 | −0.04 (15) | C16—C15—O18—C19 | 3.3 (2) |
C1—C7—O8—C9 | 178.09 (11) | C15—O18—C19—C20 | −177.75 (12) |
C7—O8—C9—N10 | 0.30 (15) | O18—C19—C20—C21 | 178.03 (12) |
C7—O8—C9—C12 | −179.01 (11) | C5—C6—N22—O23 | 104.46 (14) |
O8—C9—N10—N11 | −0.42 (16) | C1—C6—N22—O23 | −73.63 (16) |
C12—C9—N10—N11 | 178.80 (13) | C5—C6—N22—O24 | −72.95 (16) |
O8—C7—N11—N10 | −0.20 (16) | C1—C6—N22—O24 | 108.97 (15) |
Cg is the centroid of ring C12–C17. |
D—H···A | D—H | H···A | D···A | D—H···A |
C2—H2···O24i | 0.95 | 2.57 | 3.4821 (18) | 161 |
C14—H14···N10i | 0.95 | 2.41 | 3.3351 (19) | 163 |
C20—H20B···Cgii | 0.99 | 2.86 | 3.7524 (17) | 151 |
C21—H21B···Cgiii | 0.99 | 2.84 | 3.6473 (17) | 140 |
Symmetry codes: (i) x, y−1, z; (ii) −x+1, −y, −z; (iii) −x, −y, −z. |
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