organic compounds
1-Benzylsulfanyl-2-[(2-chlorophenyl)diazenyl]benzene
aDepartment of Chemistry, National Institute of Technology, Silchar 788 010, Assam, India, and bDepartment of Chemistry, Indian Institute of Technology, Guwahati 781 039, Assam, India
*Correspondence e-mail: barmanpranjit@yahoo.co.in
The title compound, C19H15ClN2S, a divalent organosulfur compound belonging to the class of ortho-mercaptoazo compounds, is non-ionic in nature. The azo group in the molecule is moved away from the S atom to attain the stable trans-azo configuration. Here the S atom is not electron deficient, so no intramolecular N⋯S interaction exists. Due to steric reasons, the molecule is non-planar: the chlorophenyl and benzyl rings are oriented at dihedral angles of 3.21 (8) and 78.18 (5)°, respectively, with respect to the thiophenyl ring. There are no hydrogen bonds and the is stabilized by van der Waals interactions.
Related literature
For background to our study of the effect of substituents at the 2′- and 4′- positions of azobenzene-2-sulfenyl compounds and related structures, see: Karmakar et al. (2001); Sanjib et al. (2004); Kakati & Chaudhuri (1968). For the reactivity of sulfenyl compounds towards biomolecules, see: Fontana et al. (1968).
Experimental
Crystal data
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Data collection: APEX2 (Bruker, 2001); cell SAINT (Bruker, 2001); data reduction: SAINT; 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/S1600536810025730/rk2215sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810025730/rk2215Isup2.hkl
To a solution of 2-benzylthioaniline in glacial acetic acid an equimolar amount of 2-chloronitrosobenzene in glacial acetic acid was added and stirred for 45 minutes. During stirring temperature was maintained between 323 to 343 K. Then the solution was kept in a dark place overnight at room temperature. Orange crystals of 2'-chloro-2-thiobenzylazobenzene were obtained, filtered off, washed with dilute acetic acid and dried, which melted at 414 K.
Hydrogen atoms were placed in calculated positions with C–H = 0.93Å and 0.97Å for aromatic and methylene H respectively and refined as riding with Uiso(H) = 1.2Ueq(C).
To investigate the effect of substituents on the 2'- and 4'-positions of azobenzene-2-sulfenyl compounds (Karmakar et al., 2001; Sanjib et al. 2004) in the formation of thiadiazolium structures by ortho azo-sulfur interaction and to study the reactivity of sulfenyl compounds towards biomolecules (Fontana et al., 1968), the title compound (Fig. 1) is studied. The sulfenyl sulfur S1 is sp3 hybridized and nucleophilic in nature for which the azo group moves away from it to attain the stable trans-azo-configuration. Such a situation was also found in azobenzene-2-sulfenyl cyanide (Kakati & Chaudhuri, 1968). The Csp3–Ssp3 [1.8064 (19)Å] bond is a normal ═N2 [1.247 (2)Å] bond length is in the expected range of an azo N═N bond length so there will be no resonance donating electron delocalization from the sulfenyl sulfur S1 into the extended of the trans-azobenzene unit [no d-resonance between (vacant d orbital) S1 and the aromatic π-cloud] and no sulfur-ortho-azo interaction. The benzyl unit is moved away from the thiophenyl unit due to steric reason. There are no hydrogen bonds and the is stabilized by Van der Waal's interactions (Fig.2).
The Csp2–S [1.7655 (19)Å] bond length is in the expected range and N1For background to our study of the effect of substituents at the 2'- and 4'- positions of azobenzene-2-sulfenyl compounds and related structures, see: Karmakar et al. (2001); Sanjib et al. (2004);Kakati & Chaudhuri (1968). For the biochemical interest of sulfenyl compounds, see: Fontana et al. (1968).
Data collection: SMART (Bruker, 2001); cell
SMART (Bruker, 2001); data reduction: SAINT (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).C19H15ClN2S | F(000) = 704 |
Mr = 338.85 | Dx = 1.334 Mg m−3 |
Monoclinic, P21/c | Melting point: 414 K |
Hall symbol: -P 2ybc | Mo Kα radiation, λ = 0.71073 Å |
a = 15.493 (2) Å | Cell parameters from 3629 reflections |
b = 5.4218 (8) Å | θ = 4.0–25.5° |
c = 20.206 (3) Å | µ = 0.35 mm−1 |
β = 96.055 (9)° | T = 296 K |
V = 1687.8 (4) Å3 | Needle, orange |
Z = 4 | 0.21 × 0.16 × 0.14 mm |
Bruker APEXII CCD area-detector diffractometer | 2140 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.042 |
Graphite monochromator | θmax = 25.5°, θmin = 2.0° |
φ– and ω–scans | h = −18→18 |
16728 measured reflections | k = −5→6 |
3139 independent reflections | l = −24→24 |
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)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.088 | H-atom parameters constrained |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0254P)2 + 0.3762P] where P = (Fo2 + 2Fc2)/3 |
3139 reflections | (Δ/σ)max < 0.001 |
208 parameters | Δρmax = 0.14 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C19H15ClN2S | V = 1687.8 (4) Å3 |
Mr = 338.85 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 15.493 (2) Å | µ = 0.35 mm−1 |
b = 5.4218 (8) Å | T = 296 K |
c = 20.206 (3) Å | 0.21 × 0.16 × 0.14 mm |
β = 96.055 (9)° |
Bruker APEXII CCD area-detector diffractometer | 2140 reflections with I > 2σ(I) |
16728 measured reflections | Rint = 0.042 |
3139 independent reflections |
R[F2 > 2σ(F2)] = 0.037 | 0 restraints |
wR(F2) = 0.088 | H-atom parameters constrained |
S = 1.01 | Δρmax = 0.14 e Å−3 |
3139 reflections | Δρmin = −0.17 e Å−3 |
208 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.14479 (3) | −0.10089 (10) | 0.08652 (2) | 0.06781 (18) | |
Cl1 | 0.50431 (4) | 0.68379 (13) | 0.11015 (3) | 0.0911 (2) | |
N2 | 0.29240 (10) | 0.2094 (3) | 0.08968 (7) | 0.0599 (4) | |
N1 | 0.36050 (10) | 0.3311 (3) | 0.10180 (7) | 0.0619 (4) | |
C7 | 0.35709 (12) | 0.5064 (4) | 0.15401 (8) | 0.0567 (5) | |
C2 | 0.42276 (12) | 0.6809 (4) | 0.16243 (9) | 0.0619 (5) | |
C3 | 0.42403 (16) | 0.8556 (4) | 0.21239 (11) | 0.0794 (6) | |
H3 | 0.4678 | 0.9737 | 0.2174 | 0.095* | |
C6 | 0.29365 (14) | 0.5079 (4) | 0.19748 (10) | 0.0759 (6) | |
H6 | 0.2493 | 0.3917 | 0.1927 | 0.091* | |
C14 | 0.07222 (13) | −0.3539 (4) | 0.06272 (10) | 0.0729 (6) | |
H14A | 0.0480 | −0.3352 | 0.0167 | 0.087* | |
H14B | 0.1036 | −0.5089 | 0.0670 | 0.087* | |
C5 | 0.29587 (17) | 0.6806 (5) | 0.24774 (11) | 0.0908 (7) | |
H5 | 0.2534 | 0.6793 | 0.2770 | 0.109* | |
C4 | 0.36019 (18) | 0.8533 (5) | 0.25459 (11) | 0.0900 (7) | |
H4 | 0.3608 | 0.9707 | 0.2882 | 0.108* | |
C9 | 0.22512 (12) | −0.1349 (3) | 0.03137 (8) | 0.0555 (5) | |
C8 | 0.29495 (12) | 0.0306 (3) | 0.03821 (8) | 0.0557 (5) | |
C13 | 0.36052 (13) | 0.0163 (4) | −0.00329 (9) | 0.0700 (6) | |
H13 | 0.4061 | 0.1286 | 0.0015 | 0.084* | |
C10 | 0.22486 (13) | −0.3157 (4) | −0.01772 (9) | 0.0657 (5) | |
H10 | 0.1796 | −0.4289 | −0.0232 | 0.079* | |
C11 | 0.29086 (14) | −0.3283 (4) | −0.05799 (10) | 0.0726 (6) | |
H11 | 0.2897 | −0.4508 | −0.0903 | 0.087* | |
C12 | 0.35836 (15) | −0.1636 (4) | −0.05150 (10) | 0.0776 (6) | |
H12 | 0.4023 | −0.1734 | −0.0794 | 0.093* | |
C16 | 0.00046 (14) | −0.5197 (4) | 0.15911 (10) | 0.0756 (6) | |
H16 | 0.0450 | −0.6346 | 0.1663 | 0.091* | |
C15 | 0.00057 (13) | −0.3535 (4) | 0.10759 (9) | 0.0611 (5) | |
C20 | −0.06639 (15) | −0.1870 (4) | 0.09826 (11) | 0.0791 (6) | |
H20 | −0.0673 | −0.0738 | 0.0636 | 0.095* | |
C19 | −0.13194 (15) | −0.1838 (5) | 0.13896 (13) | 0.0887 (7) | |
H19 | −0.1767 | −0.0695 | 0.1317 | 0.106* | |
C18 | −0.13148 (16) | −0.3489 (5) | 0.19034 (12) | 0.0871 (7) | |
H18 | −0.1756 | −0.3469 | 0.2182 | 0.104* | |
C17 | −0.06553 (16) | −0.5167 (5) | 0.20023 (11) | 0.0887 (7) | |
H17 | −0.0650 | −0.6298 | 0.2349 | 0.106* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0700 (3) | 0.0685 (4) | 0.0670 (3) | −0.0132 (3) | 0.0166 (2) | −0.0146 (3) |
Cl1 | 0.0710 (4) | 0.1094 (5) | 0.0936 (4) | −0.0207 (3) | 0.0127 (3) | 0.0060 (4) |
N2 | 0.0640 (10) | 0.0614 (10) | 0.0542 (9) | −0.0060 (9) | 0.0061 (7) | −0.0025 (8) |
N1 | 0.0625 (10) | 0.0661 (11) | 0.0570 (9) | −0.0087 (9) | 0.0061 (8) | −0.0041 (8) |
C7 | 0.0628 (12) | 0.0573 (12) | 0.0491 (10) | −0.0007 (10) | 0.0015 (9) | 0.0007 (9) |
C2 | 0.0628 (12) | 0.0643 (13) | 0.0565 (11) | −0.0009 (10) | −0.0035 (9) | 0.0068 (10) |
C3 | 0.0925 (17) | 0.0642 (15) | 0.0764 (15) | −0.0095 (12) | −0.0156 (13) | −0.0024 (12) |
C6 | 0.0813 (15) | 0.0829 (16) | 0.0654 (13) | −0.0117 (13) | 0.0172 (11) | −0.0086 (12) |
C14 | 0.0833 (15) | 0.0647 (14) | 0.0733 (13) | −0.0175 (11) | 0.0208 (11) | −0.0102 (11) |
C5 | 0.1033 (19) | 0.102 (2) | 0.0701 (15) | 0.0007 (16) | 0.0217 (13) | −0.0170 (14) |
C4 | 0.117 (2) | 0.0813 (18) | 0.0691 (15) | 0.0060 (16) | −0.0025 (15) | −0.0192 (13) |
C9 | 0.0639 (12) | 0.0526 (12) | 0.0497 (10) | 0.0006 (9) | 0.0048 (9) | 0.0017 (9) |
C8 | 0.0619 (12) | 0.0567 (12) | 0.0479 (10) | 0.0004 (10) | 0.0038 (9) | −0.0004 (9) |
C13 | 0.0678 (13) | 0.0787 (15) | 0.0651 (12) | −0.0100 (11) | 0.0147 (10) | −0.0071 (11) |
C10 | 0.0750 (14) | 0.0611 (13) | 0.0613 (12) | −0.0067 (11) | 0.0081 (10) | −0.0063 (10) |
C11 | 0.0916 (16) | 0.0682 (15) | 0.0598 (12) | 0.0007 (13) | 0.0162 (11) | −0.0110 (10) |
C12 | 0.0816 (16) | 0.0851 (17) | 0.0697 (13) | −0.0026 (13) | 0.0243 (11) | −0.0105 (12) |
C16 | 0.0816 (15) | 0.0670 (15) | 0.0794 (14) | 0.0016 (12) | 0.0139 (12) | 0.0072 (12) |
C15 | 0.0672 (13) | 0.0541 (13) | 0.0622 (12) | −0.0105 (10) | 0.0078 (10) | −0.0069 (10) |
C20 | 0.0867 (16) | 0.0689 (15) | 0.0822 (15) | −0.0033 (13) | 0.0122 (13) | 0.0096 (12) |
C19 | 0.0774 (16) | 0.0795 (17) | 0.1111 (19) | 0.0054 (13) | 0.0188 (14) | −0.0010 (16) |
C18 | 0.0842 (17) | 0.0862 (19) | 0.0961 (18) | −0.0160 (15) | 0.0348 (14) | −0.0174 (15) |
C17 | 0.108 (2) | 0.0824 (18) | 0.0803 (15) | −0.0092 (16) | 0.0300 (14) | 0.0124 (13) |
S1—C9 | 1.7655 (19) | C9—C8 | 1.401 (2) |
S1—C14 | 1.8064 (19) | C8—C13 | 1.386 (2) |
Cl1—C2 | 1.730 (2) | C13—C12 | 1.377 (3) |
N2—N1 | 1.247 (2) | C13—H13 | 0.9300 |
N2—C8 | 1.425 (2) | C10—C11 | 1.374 (3) |
N1—C7 | 1.425 (2) | C10—H10 | 0.9300 |
C7—C2 | 1.387 (3) | C11—C12 | 1.371 (3) |
C7—C6 | 1.385 (2) | C11—H11 | 0.9300 |
C2—C3 | 1.383 (3) | C12—H12 | 0.9300 |
C3—C4 | 1.372 (3) | C16—C15 | 1.377 (3) |
C3—H3 | 0.9300 | C16—C17 | 1.384 (3) |
C6—C5 | 1.379 (3) | C16—H16 | 0.9300 |
C6—H6 | 0.9300 | C15—C20 | 1.373 (3) |
C14—C15 | 1.506 (2) | C20—C19 | 1.373 (3) |
C14—H14A | 0.9700 | C20—H20 | 0.9300 |
C14—H14B | 0.9700 | C19—C18 | 1.371 (3) |
C5—C4 | 1.364 (3) | C19—H19 | 0.9300 |
C5—H5 | 0.9300 | C18—C17 | 1.367 (3) |
C4—H4 | 0.9300 | C18—H18 | 0.9300 |
C9—C10 | 1.394 (2) | C17—H17 | 0.9300 |
C9—S1—C14 | 102.30 (9) | C9—C8—N2 | 115.27 (16) |
N1—N2—C8 | 114.54 (15) | C12—C13—C8 | 120.21 (19) |
N2—N1—C7 | 113.69 (15) | C12—C13—H13 | 119.9 |
C2—C7—C6 | 118.60 (18) | C8—C13—H13 | 119.9 |
C2—C7—N1 | 117.50 (17) | C11—C10—C9 | 120.64 (19) |
C6—C7—N1 | 123.87 (18) | C11—C10—H10 | 119.7 |
C3—C2—C7 | 120.70 (19) | C9—C10—H10 | 119.7 |
C3—C2—Cl1 | 118.97 (17) | C12—C11—C10 | 121.27 (19) |
C7—C2—Cl1 | 120.33 (16) | C12—C11—H11 | 119.4 |
C4—C3—C2 | 119.4 (2) | C10—C11—H11 | 119.4 |
C4—C3—H3 | 120.3 | C11—C12—C13 | 119.37 (19) |
C2—C3—H3 | 120.3 | C11—C12—H12 | 120.3 |
C5—C6—C7 | 120.4 (2) | C13—C12—H12 | 120.3 |
C5—C6—H6 | 119.8 | C15—C16—C17 | 120.4 (2) |
C7—C6—H6 | 119.8 | C15—C16—H16 | 119.8 |
C15—C14—S1 | 108.44 (13) | C17—C16—H16 | 119.8 |
C15—C14—H14A | 110.0 | C20—C15—C16 | 118.22 (19) |
S1—C14—H14A | 110.0 | C20—C15—C14 | 120.84 (19) |
C15—C14—H14B | 110.0 | C16—C15—C14 | 120.9 (2) |
S1—C14—H14B | 110.0 | C15—C20—C19 | 121.5 (2) |
H14A—C14—H14B | 108.4 | C15—C20—H20 | 119.3 |
C4—C5—C6 | 120.1 (2) | C19—C20—H20 | 119.3 |
C4—C5—H5 | 119.9 | C18—C19—C20 | 120.0 (2) |
C6—C5—H5 | 119.9 | C18—C19—H19 | 120.0 |
C5—C4—C3 | 120.7 (2) | C20—C19—H19 | 120.0 |
C5—C4—H4 | 119.7 | C17—C18—C19 | 119.3 (2) |
C3—C4—H4 | 119.7 | C17—C18—H18 | 120.3 |
C10—C9—C8 | 117.69 (17) | C19—C18—H18 | 120.3 |
C10—C9—S1 | 124.96 (15) | C18—C17—C16 | 120.5 (2) |
C8—C9—S1 | 117.34 (14) | C18—C17—H17 | 119.7 |
C13—C8—C9 | 120.82 (17) | C16—C17—H17 | 119.7 |
C13—C8—N2 | 123.91 (17) | ||
C8—N2—N1—C7 | −179.16 (14) | S1—C9—C8—N2 | −0.1 (2) |
N2—N1—C7—C2 | −168.03 (16) | N1—N2—C8—C13 | −10.4 (3) |
N2—N1—C7—C6 | 13.7 (3) | N1—N2—C8—C9 | 169.87 (16) |
C6—C7—C2—C3 | −1.2 (3) | C9—C8—C13—C12 | −0.8 (3) |
N1—C7—C2—C3 | −179.52 (16) | N2—C8—C13—C12 | 179.50 (18) |
C6—C7—C2—Cl1 | 179.09 (15) | C8—C9—C10—C11 | −0.5 (3) |
N1—C7—C2—Cl1 | 0.8 (2) | S1—C9—C10—C11 | −179.50 (15) |
C7—C2—C3—C4 | 1.0 (3) | C9—C10—C11—C12 | −0.4 (3) |
Cl1—C2—C3—C4 | −179.29 (17) | C10—C11—C12—C13 | 0.6 (3) |
C2—C7—C6—C5 | 0.3 (3) | C8—C13—C12—C11 | 0.0 (3) |
N1—C7—C6—C5 | 178.57 (19) | C17—C16—C15—C20 | −0.2 (3) |
C9—S1—C14—C15 | 178.30 (14) | C17—C16—C15—C14 | 179.67 (19) |
C7—C6—C5—C4 | 0.7 (3) | S1—C14—C15—C20 | 76.9 (2) |
C6—C5—C4—C3 | −0.9 (4) | S1—C14—C15—C16 | −103.02 (19) |
C2—C3—C4—C5 | 0.1 (3) | C16—C15—C20—C19 | 0.2 (3) |
C14—S1—C9—C10 | 1.43 (19) | C14—C15—C20—C19 | −179.71 (19) |
C14—S1—C9—C8 | −177.62 (14) | C15—C20—C19—C18 | 0.1 (4) |
C10—C9—C8—C13 | 1.0 (3) | C20—C19—C18—C17 | −0.4 (4) |
S1—C9—C8—C13 | −179.84 (15) | C19—C18—C17—C16 | 0.3 (4) |
C10—C9—C8—N2 | −179.24 (16) | C15—C16—C17—C18 | 0.0 (3) |
Experimental details
Crystal data | |
Chemical formula | C19H15ClN2S |
Mr | 338.85 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 296 |
a, b, c (Å) | 15.493 (2), 5.4218 (8), 20.206 (3) |
β (°) | 96.055 (9) |
V (Å3) | 1687.8 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.35 |
Crystal size (mm) | 0.21 × 0.16 × 0.14 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 16728, 3139, 2140 |
Rint | 0.042 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.088, 1.01 |
No. of reflections | 3139 |
No. of parameters | 208 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.14, −0.17 |
Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).
Acknowledgements
TB and RS thank the Council of Scientific and Industrial Research (CSIR), Government of India, New Delhi, for the award of fellowships.
References
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Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
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To investigate the effect of substituents on the 2'- and 4'-positions of azobenzene-2-sulfenyl compounds (Karmakar et al., 2001; Sanjib et al. 2004) in the formation of thiadiazolium structures by ortho azo-sulfur interaction and to study the reactivity of sulfenyl compounds towards biomolecules (Fontana et al., 1968), the title compound (Fig. 1) is studied. The sulfenyl sulfur S1 is sp3 hybridized and nucleophilic in nature for which the azo group moves away from it to attain the stable trans-azo-configuration. Such a situation was also found in azobenzene-2-sulfenyl cyanide (Kakati & Chaudhuri, 1968). The Csp3–Ssp3 [1.8064 (19)Å] bond is a normal covalent bond. The Csp2–S [1.7655 (19)Å] bond length is in the expected range and N1═N2 [1.247 (2)Å] bond length is in the expected range of an azo N═N bond length so there will be no resonance donating electron delocalization from the sulfenyl sulfur S1 into the extended conjugated system of the trans-azobenzene unit [no d-resonance between (vacant d orbital) S1 and the aromatic π-cloud] and no sulfur-ortho-azo interaction. The benzyl unit is moved away from the thiophenyl unit due to steric reason. There are no hydrogen bonds and the crystal structure is stabilized by Van der Waal's interactions (Fig.2).