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organic compounds
Diethyl 4,4′-(diazenediyl)dibenzoate
aDepartment of Chemistry and Environmental Engineering, Anyang Institute of Technology, Henan 455000, People's Republic of China
*Correspondence e-mail: 119yyz@163.com
The full molecule of the title compound, C18H18N2O4, is generated by the application of an inversion centre. There are strong π–π interactions between adjacent molecules with a centroid–centroid distance of 3.298 (2)Å.
Related literature
For the properties and structures of related compounds, see: Altomare et al. (2005;) Kubo et al. (2005
); Harada et al. (1997
).
Experimental
Crystal data
|
Data collection: APEX2 (Bruker, 2005); cell SAINT-Plus (Bruker, 2001
); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008
); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008
); molecular graphics: SHELXTL (Sheldrick, 2008
); software used to prepare material for publication: SHELXTL.
Supporting information
https://doi.org/10.1107/S1600536811036877/aa2020sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811036877/aa2020Isup2.hkl
1.0 g of azobenzene-4,4'-dicarbonylchloride and 20 ml of ethanol were stirred at 353 K for 4 h. After cooling to room temperature a red deposit was obtained. It was then recrystallized from CH2Cl2 to give red crystals suitable for X-ray diffraction analysis.
All H atoms were placed in geometrically idealized positions (C—H = 0.93, 0.96 and 0.97 Å) and treated as riding on their parent atoms with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(C).
Synthesis, elucidation of crystal structures, and investigation of physical properties of new liquid crystals are important for studying the relationship between molecular stuctures and mesophases. (Kubo et al., 2005). As a contribution to these fields, We report here the synthesis and structure of the title compound.
The title compound (Fig. 1), C18H18N2O4, shows crystallographic inversion symmetry. The intersection angle between two benzene rings is consistent with that of azobenzene (0 °). (Harada et al., 1997) No classic hydrogen bonds are observed in the crystal. There are strong π-π interactions between planar adjacent molecules with the interplanar distance 3.298 Å.
For the properties and structures of related compounds, see: Altomare et al. (2005;) Kubo et al. (2005); Harada et al. (1997).
Data collection: APEX2 (Bruker, 2005); cell
SAINT-Plus (Bruker, 2001); data reduction: SAINT-Plus (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008). ![]() | Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. Symmetry code: (i) 2 - x, - y, 2 - z |
![]() | Fig. 2. π-π interaction of the molecules. |
C18H18N2O4 | F(000) = 344 |
Mr = 326.34 | Dx = 1.359 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 5335 reflections |
a = 14.844 (3) Å | θ = 3.5–28.4° |
b = 4.5731 (9) Å | µ = 0.10 mm−1 |
c = 11.814 (2) Å | T = 293 K |
β = 95.88 (3)° | Block, red |
V = 797.7 (3) Å3 | 0.40 × 0.20 × 0.20 mm |
Z = 2 |
Bruker APEXII CCD diffractometer | 1639 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.022 |
Graphite monochromator | θmax = 28.4°, θmin = 3.5° |
φ and ω scans | h = −19→19 |
13606 measured reflections | k = −6→6 |
1976 independent reflections | l = −15→15 |
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)] = 0.050 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.149 | H-atom parameters constrained |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0736P)2 + 0.2526P] where P = (Fo2 + 2Fc2)/3 |
1976 reflections | (Δ/σ)max < 0.001 |
109 parameters | Δρmax = 0.31 e Å−3 |
0 restraints | Δρmin = −0.25 e Å−3 |
C18H18N2O4 | V = 797.7 (3) Å3 |
Mr = 326.34 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 14.844 (3) Å | µ = 0.10 mm−1 |
b = 4.5731 (9) Å | T = 293 K |
c = 11.814 (2) Å | 0.40 × 0.20 × 0.20 mm |
β = 95.88 (3)° |
Bruker APEXII CCD diffractometer | 1639 reflections with I > 2σ(I) |
13606 measured reflections | Rint = 0.022 |
1976 independent reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.149 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.31 e Å−3 |
1976 reflections | Δρmin = −0.25 e Å−3 |
109 parameters |
x | y | z | Uiso*/Ueq | ||
C1 | 0.92686 (8) | 0.2685 (3) | 0.93120 (11) | 0.0327 (3) | |
C2 | 0.86559 (9) | 0.3422 (3) | 1.00838 (12) | 0.0390 (3) | |
H2A | 0.8699 | 0.2558 | 1.0800 | 0.047* | |
C3 | 0.92142 (9) | 0.4028 (3) | 0.82545 (11) | 0.0353 (3) | |
H3A | 0.9633 | 0.3565 | 0.7748 | 0.042* | |
C4 | 0.85380 (9) | 0.6061 (3) | 0.79487 (11) | 0.0360 (3) | |
H4A | 0.8502 | 0.6954 | 0.7238 | 0.043* | |
C5 | 0.79835 (9) | 0.5450 (3) | 0.97752 (12) | 0.0398 (3) | |
H5A | 0.7573 | 0.5946 | 1.0288 | 0.048* | |
C6 | 0.79149 (8) | 0.6754 (3) | 0.87074 (11) | 0.0340 (3) | |
C7 | 0.71536 (9) | 0.8857 (3) | 0.84138 (13) | 0.0407 (3) | |
C8 | 0.64597 (12) | 1.2071 (4) | 0.69866 (17) | 0.0604 (5) | |
H8A | 0.6696 | 1.3527 | 0.6498 | 0.072* | |
H8B | 0.6251 | 1.3072 | 0.7635 | 0.072* | |
C9 | 0.56912 (14) | 1.0525 (6) | 0.6352 (2) | 0.0848 (8) | |
H9A | 0.5226 | 1.1908 | 0.6103 | 0.127* | |
H9B | 0.5453 | 0.9099 | 0.6838 | 0.127* | |
H9C | 0.5896 | 0.9565 | 0.5702 | 0.127* | |
N1 | 0.99820 (7) | 0.0589 (2) | 0.95208 (9) | 0.0354 (3) | |
O1 | 0.65887 (8) | 0.9411 (3) | 0.90410 (11) | 0.0645 (4) | |
O2 | 0.71756 (7) | 1.0021 (3) | 0.73787 (10) | 0.0502 (3) |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0323 (6) | 0.0305 (6) | 0.0344 (7) | −0.0026 (5) | −0.0018 (5) | −0.0015 (5) |
C2 | 0.0417 (7) | 0.0438 (8) | 0.0315 (7) | −0.0004 (6) | 0.0032 (5) | 0.0052 (5) |
C3 | 0.0359 (6) | 0.0373 (7) | 0.0329 (7) | 0.0013 (5) | 0.0039 (5) | −0.0006 (5) |
C4 | 0.0392 (6) | 0.0380 (7) | 0.0303 (6) | 0.0012 (5) | 0.0008 (5) | 0.0017 (5) |
C5 | 0.0363 (6) | 0.0469 (8) | 0.0368 (7) | 0.0007 (6) | 0.0071 (5) | −0.0010 (6) |
C6 | 0.0311 (6) | 0.0337 (6) | 0.0361 (7) | −0.0019 (5) | −0.0016 (5) | −0.0033 (5) |
C7 | 0.0344 (6) | 0.0404 (7) | 0.0462 (8) | 0.0016 (5) | −0.0005 (5) | −0.0048 (6) |
C8 | 0.0546 (9) | 0.0584 (10) | 0.0651 (11) | 0.0187 (8) | −0.0086 (8) | 0.0054 (9) |
C9 | 0.0547 (10) | 0.1064 (19) | 0.0875 (16) | 0.0183 (11) | −0.0209 (10) | −0.0167 (14) |
N1 | 0.0370 (6) | 0.0347 (6) | 0.0334 (6) | −0.0007 (4) | −0.0009 (4) | 0.0008 (4) |
O1 | 0.0515 (7) | 0.0768 (9) | 0.0673 (8) | 0.0215 (6) | 0.0171 (6) | 0.0054 (7) |
O2 | 0.0468 (6) | 0.0546 (7) | 0.0475 (6) | 0.0157 (5) | −0.0033 (5) | 0.0054 (5) |
C1—C3 | 1.3870 (18) | C6—C7 | 1.4972 (18) |
C1—C2 | 1.3934 (19) | C7—O1 | 1.2015 (18) |
C1—N1 | 1.4311 (17) | C7—O2 | 1.3371 (19) |
C2—C5 | 1.384 (2) | C8—O2 | 1.4568 (18) |
C2—H2A | 0.9300 | C8—C9 | 1.479 (3) |
C3—C4 | 1.3883 (18) | C8—H8A | 0.9700 |
C3—H3A | 0.9300 | C8—H8B | 0.9700 |
C4—C6 | 1.3890 (19) | C9—H9A | 0.9600 |
C4—H4A | 0.9300 | C9—H9B | 0.9600 |
C5—C6 | 1.3896 (19) | C9—H9C | 0.9600 |
C5—H5A | 0.9300 | N1—N1i | 1.250 (2) |
C3—C1—C2 | 120.05 (12) | O1—C7—O2 | 124.33 (14) |
C3—C1—N1 | 115.19 (12) | O1—C7—C6 | 123.40 (14) |
C2—C1—N1 | 124.76 (12) | O2—C7—C6 | 112.27 (12) |
C5—C2—C1 | 119.41 (13) | O2—C8—C9 | 110.67 (16) |
C5—C2—H2A | 120.3 | O2—C8—H8A | 109.5 |
C1—C2—H2A | 120.3 | C9—C8—H8A | 109.5 |
C1—C3—C4 | 120.31 (12) | O2—C8—H8B | 109.5 |
C1—C3—H3A | 119.8 | C9—C8—H8B | 109.5 |
C4—C3—H3A | 119.8 | H8A—C8—H8B | 108.1 |
C3—C4—C6 | 119.77 (12) | C8—C9—H9A | 109.5 |
C3—C4—H4A | 120.1 | C8—C9—H9B | 109.5 |
C6—C4—H4A | 120.1 | H9A—C9—H9B | 109.5 |
C2—C5—C6 | 120.71 (13) | C8—C9—H9C | 109.5 |
C2—C5—H5A | 119.6 | H9A—C9—H9C | 109.5 |
C6—C5—H5A | 119.6 | H9B—C9—H9C | 109.5 |
C4—C6—C5 | 119.73 (12) | N1i—N1—C1 | 114.02 (14) |
C4—C6—C7 | 122.27 (12) | C7—O2—C8 | 117.50 (13) |
C5—C6—C7 | 117.99 (12) | ||
C3—C1—C2—C5 | 1.4 (2) | C4—C6—C7—O1 | 177.29 (15) |
N1—C1—C2—C5 | −178.86 (12) | C5—C6—C7—O1 | −2.0 (2) |
C2—C1—C3—C4 | −1.5 (2) | C4—C6—C7—O2 | −2.41 (19) |
N1—C1—C3—C4 | 178.77 (11) | C5—C6—C7—O2 | 178.28 (12) |
C1—C3—C4—C6 | 0.1 (2) | C3—C1—N1—N1i | 179.91 (13) |
C1—C2—C5—C6 | 0.0 (2) | C2—C1—N1—N1i | 0.2 (2) |
C3—C4—C6—C5 | 1.2 (2) | O1—C7—O2—C8 | −0.7 (2) |
C3—C4—C6—C7 | −178.06 (12) | C6—C7—O2—C8 | 179.05 (12) |
C2—C5—C6—C4 | −1.3 (2) | C9—C8—O2—C7 | −91.4 (2) |
C2—C5—C6—C7 | 178.04 (12) |
Symmetry code: (i) −x+2, −y, −z+2. |
Experimental details
Crystal data | |
Chemical formula | C18H18N2O4 |
Mr | 326.34 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 14.844 (3), 4.5731 (9), 11.814 (2) |
β (°) | 95.88 (3) |
V (Å3) | 797.7 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.40 × 0.20 × 0.20 |
Data collection | |
Diffractometer | Bruker APEXII CCD |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 13606, 1976, 1639 |
Rint | 0.022 |
(sin θ/λ)max (Å−1) | 0.669 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.149, 1.07 |
No. of reflections | 1976 |
No. of parameters | 109 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.31, −0.25 |
Computer programs: APEX2 (Bruker, 2005), SAINT-Plus (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Acknowledgements
This work was supported by the key subject of applied chemistry of Anyang Institute of Technology.
References
Altomare, A., Ciardelli, F., Marchini, M. & Solaro, R. (2005). Polymer, 46, 2086–2096. Web of Science CrossRef CAS Google Scholar
Bruker (2001). SAINT-Plus. Bruker AXS Inc., Madison, Wisconsin, USA Google Scholar
Bruker (2005). APEX2. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Harada, J., Ogawa, K. & Tomoda, S. (1997). Acta Cryst. B53, 662–672. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Kubo, K., Mori, A., Ujiie, S. & Tschierske, C. (2005). J. Oleo Sci. 54, 179–183. CrossRef CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Synthesis, elucidation of crystal structures, and investigation of physical properties of new liquid crystals are important for studying the relationship between molecular stuctures and mesophases. (Kubo et al., 2005). As a contribution to these fields, We report here the synthesis and structure of the title compound.
The title compound (Fig. 1), C18H18N2O4, shows crystallographic inversion symmetry. The intersection angle between two benzene rings is consistent with that of azobenzene (0 °). (Harada et al., 1997) No classic hydrogen bonds are observed in the crystal. There are strong π-π interactions between planar adjacent molecules with the interplanar distance 3.298 Å.