research communications
of 3,5-dimethylphenyl 2-nitrobenzenesulfonate
aDepartment of Chemistry, Grand Valley State University, 1 Campus Dr., Allendale, MI 49401, USA, and bCenter for Crystallographic Research, Department of Chemistry, Michigan State University, 578 S. Shaw Lane, East Lansing, MI 48824, USA
*Correspondence e-mail: ngassaf@gvsu.edu
The title compound, C14H13NO5S, was synthesized via a nucleophilic between 3,5-dimethylphenol and 2-nitrobenzenesulfonyl chloride. The aromatic rings attached to the SO3 group are oriented in a gauche fashion around the ester S—O bond, with a C—S—O—C torsion angle of 84.68 (11)°. The molecules form centrosymmetric dimers via π–π stacking interactions between 3,5-dimethylphenyl groups (centroid–centroid distance = 3.709 Å). An intermolecular S=O⋯N interaction between the sulfonyl and nitro groups, with an O⋯N distance of 2.9840 (18) Å, organizes the dimers into columns extending along [011]. These columns are further assembled into (111) layers through C—H⋯O interactions.
Keywords: crystal structure; nitrobenzenesulfonate; N(nitro)⋯O interactions; C—H⋯O interactions; π–π interactions.
CCDC reference: 1418463
1. Chemical context
Microtubules form a major component of the cytoskeleton and have been implicated in a wide variety of cellular functions, such as cell division (Jordan & Wilson, 2004). Microtubules therefore have been targeted in the design of drugs for the treatment of various forms of cancer (Spencer & Faulds, 1994; Teicher, 2008; Trivedi et al., 2008). For example, Combretastatin A-4 (CA-4) has been shown to target tumor vasculature (Griggs et al., 2001). Most known antimicrotubules have poor biopharmaceutical properties, uch as chemoresistance and toxicity (Islam et al., 2003; Fortin et al., 2011).
Research in the field for the synthesis of new antimicrotubule compounds has been geared towards compounds with improved biopharmaceutical properties (Fortin et al., 2011). To this end, Fortin and co-workers have designed and synthesized various sulfonate derivatives, which have been tested as new tubulin inhibitors mimicking Combretastatin A-4 (Fig. 1).
A series of sulfonate derivatives have shown promise as anticancer drugs, with some having lower toxicity than CA-4 (Fortin et al., 2011). We embarked on the synthesis of sulfonate derivatives with the long-term goal of investigating the effect of the benzene-ring substituents on the cytotoxicity of the sulfonate derivatives. To the best of our knowledge, despite the simplicity of the sulfonate derivatives, there has been no relevant previous crystallographic studies. Therefore, we report here the synthesis and of 3,5-dimethylphenyl 2-nitrobenzenesulfonate.
2. Structural commentary
In the title molecule (Fig. 2), the O1=S1=O2 and C1—S1—O3 bond angles of 119.41 (7) and 104.16 (6)° are typical for phenyl benzenesulfonates with a gauche conformation around the ester S—O bond. The torsion angle C1—S1—O3—C7 around the ester bond is −84.68 (11)°. Owing to between the ortho substituents of the benzene ring, the nitro group is twisted relative to the benzene best plane by 39.91 (2)°, so that the shortest contact of 2.7941 (16) Å between the O atoms of these groups is close to the sum of the van der Waals radii.
3. Supramolecular features
The molecules of the title compound form centrosymmetric dimers via intermolecular π–π stacking interactions between the relatively electron-rich C7–C12 benzene rings (Fig. 3), with a plane-to-plane distance of 3.4147 (15) Å. The aromatic rings are stacked with an offset, and the distance between the centroids of these rings is 3.709 (12) Å. Another centrosymmetric dimer is formed by an S=O⋯N interaction, with an N1⋯O2 interatomic distance of 2.9840 (18) Å. O⋯N(nitro) interactions between nitro groups have been discussed in the literature (Daszkiewicz, 2013; Caracelli et al., 2014) and we report here the case of sulfonyl and nitro group interactions. Both types of dimers are assembled into a column-type structure extending along [011] (Fig. 4).
however, nonclassical C—H⋯O interactions between aromatic-ring H atoms and sulfonyl and nitro group O atoms organize the [011] columns into (111) layers. The geometry of these interactions is given in Table 14. Database survey
The Cambridge Structural Database (CSD, Version 5.36 with two updates; Groom & Allen, 2014) contains three structures with an o-nitroarylsulfonyl moiety bonded to an aromatic ring through an ester linkage. These are CSD refcodes FEMQUK (Ichikawa et al., 2004), MIBZUT (Pelly et al., 2007), and FEMRIZ (Ichikawa et al., 2004). Like in the title compound, the aromatic substituents of the SO3 group are oriented gauche around the ester S—O bond and the absolute value of the C—S—O—C torsion angle is in the range 85.9 (3)–103.43 (13)°. In each of these structures there are either intra- or intermolecular S=O⋯N interactions between the sulfonate and o-nitro groups.
5. Synthesis and crystallization
3,5-Dimethylphenol (2.44 g, 20 mmol) was dissolved in chilled dichloromethane (25 ml). This was followed by the addition of pyridine (3.2 ml, 40 mmol). The resulting solution was cooled in an ice bath under an N2 atmosphere, followed by the addition of 2-nitrobenzenesulfonyl chloride (4.43 g, 20 mmol) portion-wise. The mixture was stirred at 273 K for 30 mins and then at room temperature for 24 h. The product precipitated from the reaction mixture after sitting at 277 K for two weeks. The product was redissolved in dichloromethane, and the solvent was allowed to evaporate slowly to give large block-shaped crystals that were suitable for analysis by X-ray diffraction (m.p. 374–378 K).
6. Refinement
Crystal data, data collection and structure . H atoms were placed in calculated positions and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C) for CH groups and 1.5Ueq(C) for methyl groups.
details are summarized in Table 2Supporting information
CCDC reference: 1418463
https://doi.org/10.1107/S2056989015015078/gk2639sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989015015078/gk2639Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989015015078/gk2639Isup3.cml
Data collection: APEX2 (Bruker, 2013); cell
SAINT (Bruker, 2013); data reduction: SAINT (Bruker, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: CrystalMaker (Palmer, 2007); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009; Bourhis et al., 2015).C14H13NO5S | Z = 2 |
Mr = 307.31 | F(000) = 320 |
Triclinic, P1 | Dx = 1.528 Mg m−3 |
a = 7.9958 (4) Å | Cu Kα radiation, λ = 1.54178 Å |
b = 7.9991 (5) Å | Cell parameters from 8863 reflections |
c = 12.0238 (3) Å | θ = 3.8–72.3° |
α = 83.908 (3)° | µ = 2.37 mm−1 |
β = 76.286 (3)° | T = 173 K |
γ = 63.411 (4)° | Block, colourless |
V = 668.10 (6) Å3 | 0.38 × 0.34 × 0.21 mm |
Bruker APEXII CCD diffractometer | 2519 independent reflections |
Radiation source: sealed tube | 2461 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.022 |
Detector resolution: 8 pixels mm-1 | θmax = 72.1°, θmin = 3.8° |
φ and ω scans | h = −9→9 |
Absorption correction: multi-scan (SADABS; Bruker, 2013) | k = −9→9 |
Tmin = 0.630, Tmax = 0.754 | l = −14→14 |
10317 measured reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.035 | H-atom parameters constrained |
wR(F2) = 0.092 | w = 1/[σ2(Fo2) + (0.0559P)2 + 0.3536P] where P = (Fo2 + 2Fc2)/3 |
S = 1.05 | (Δ/σ)max < 0.001 |
2519 reflections | Δρmax = 0.33 e Å−3 |
192 parameters | Δρmin = −0.50 e Å−3 |
0 restraints |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
S1 | 0.32156 (5) | 0.85859 (5) | 0.36621 (3) | 0.01694 (13) | |
O1 | 0.27175 (16) | 1.05073 (15) | 0.33973 (10) | 0.0239 (3) | |
O2 | 0.22079 (15) | 0.81004 (16) | 0.46826 (9) | 0.0240 (3) | |
O3 | 0.29830 (15) | 0.76150 (15) | 0.26599 (9) | 0.0193 (2) | |
O4 | 0.46725 (16) | 0.43665 (16) | 0.39045 (10) | 0.0240 (3) | |
O5 | 0.73130 (19) | 0.28883 (18) | 0.26840 (12) | 0.0375 (3) | |
N1 | 0.62367 (18) | 0.41785 (18) | 0.33520 (11) | 0.0201 (3) | |
C1 | 0.5719 (2) | 0.7475 (2) | 0.36177 (12) | 0.0171 (3) | |
C2 | 0.6508 (2) | 0.8662 (2) | 0.37453 (13) | 0.0216 (3) | |
H2 | 0.5728 | 0.9973 | 0.3801 | 0.026* | |
C3 | 0.8425 (2) | 0.7951 (3) | 0.37920 (14) | 0.0258 (4) | |
H3 | 0.8939 | 0.8771 | 0.3902 | 0.031* | |
C4 | 0.9587 (2) | 0.6047 (3) | 0.36792 (14) | 0.0265 (4) | |
H4 | 1.0898 | 0.5564 | 0.3711 | 0.032* | |
C5 | 0.8841 (2) | 0.4845 (2) | 0.35195 (13) | 0.0227 (3) | |
H5 | 0.9643 | 0.3542 | 0.3426 | 0.027* | |
C6 | 0.6920 (2) | 0.5556 (2) | 0.34977 (12) | 0.0182 (3) | |
C7 | 0.3244 (2) | 0.8273 (2) | 0.15112 (12) | 0.0175 (3) | |
C8 | 0.1844 (2) | 0.9933 (2) | 0.12119 (13) | 0.0200 (3) | |
H8 | 0.0770 | 1.0683 | 0.1773 | 0.024* | |
C9 | 0.2044 (2) | 1.0482 (2) | 0.00677 (14) | 0.0214 (3) | |
C10 | 0.3619 (2) | 0.9314 (2) | −0.07306 (13) | 0.0217 (3) | |
H10 | 0.3744 | 0.9677 | −0.1513 | 0.026* | |
C11 | 0.5014 (2) | 0.7635 (2) | −0.04207 (13) | 0.0198 (3) | |
C12 | 0.4822 (2) | 0.7111 (2) | 0.07297 (13) | 0.0186 (3) | |
H12 | 0.5755 | 0.5979 | 0.0971 | 0.022* | |
C13 | 0.0582 (3) | 1.2305 (2) | −0.02968 (16) | 0.0294 (4) | |
H13A | −0.0609 | 1.2720 | 0.0288 | 0.044* | |
H13B | 0.0333 | 1.2131 | −0.1026 | 0.044* | |
H13C | 0.1069 | 1.3249 | −0.0390 | 0.044* | |
C14 | 0.6690 (2) | 0.6430 (2) | −0.13189 (14) | 0.0249 (3) | |
H14A | 0.6251 | 0.6435 | −0.2015 | 0.037* | |
H14B | 0.7263 | 0.5147 | −0.1032 | 0.037* | |
H14C | 0.7647 | 0.6923 | −0.1494 | 0.037* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.01488 (19) | 0.0172 (2) | 0.0159 (2) | −0.00464 (15) | −0.00261 (13) | −0.00112 (14) |
O1 | 0.0254 (6) | 0.0177 (6) | 0.0258 (6) | −0.0055 (4) | −0.0081 (5) | −0.0009 (5) |
O2 | 0.0186 (5) | 0.0292 (6) | 0.0188 (5) | −0.0075 (5) | −0.0002 (4) | 0.0000 (5) |
O3 | 0.0225 (5) | 0.0206 (5) | 0.0174 (5) | −0.0113 (4) | −0.0061 (4) | 0.0026 (4) |
O4 | 0.0227 (6) | 0.0257 (6) | 0.0254 (6) | −0.0129 (5) | −0.0043 (5) | 0.0023 (5) |
O5 | 0.0340 (7) | 0.0311 (7) | 0.0430 (8) | −0.0111 (6) | 0.0021 (6) | −0.0198 (6) |
N1 | 0.0215 (6) | 0.0181 (6) | 0.0186 (6) | −0.0063 (5) | −0.0052 (5) | 0.0000 (5) |
C1 | 0.0157 (7) | 0.0211 (7) | 0.0126 (6) | −0.0072 (6) | −0.0014 (5) | −0.0007 (6) |
C2 | 0.0236 (7) | 0.0231 (8) | 0.0179 (7) | −0.0108 (6) | −0.0017 (6) | −0.0027 (6) |
C3 | 0.0258 (8) | 0.0362 (9) | 0.0219 (8) | −0.0194 (7) | −0.0024 (6) | −0.0044 (7) |
C4 | 0.0170 (7) | 0.0397 (10) | 0.0227 (8) | −0.0124 (7) | −0.0034 (6) | −0.0006 (7) |
C5 | 0.0183 (7) | 0.0240 (8) | 0.0195 (7) | −0.0046 (6) | −0.0021 (6) | −0.0001 (6) |
C6 | 0.0187 (7) | 0.0212 (7) | 0.0137 (7) | −0.0087 (6) | −0.0017 (5) | −0.0006 (6) |
C7 | 0.0210 (7) | 0.0189 (7) | 0.0169 (7) | −0.0116 (6) | −0.0064 (6) | 0.0016 (6) |
C8 | 0.0191 (7) | 0.0189 (7) | 0.0226 (8) | −0.0074 (6) | −0.0060 (6) | −0.0029 (6) |
C9 | 0.0244 (7) | 0.0177 (7) | 0.0256 (8) | −0.0098 (6) | −0.0114 (6) | 0.0021 (6) |
C10 | 0.0304 (8) | 0.0213 (8) | 0.0181 (7) | −0.0145 (7) | −0.0086 (6) | 0.0030 (6) |
C11 | 0.0238 (7) | 0.0188 (7) | 0.0208 (7) | −0.0127 (6) | −0.0038 (6) | −0.0023 (6) |
C12 | 0.0196 (7) | 0.0146 (7) | 0.0233 (8) | −0.0077 (6) | −0.0073 (6) | 0.0010 (6) |
C13 | 0.0324 (9) | 0.0217 (8) | 0.0327 (9) | −0.0074 (7) | −0.0158 (7) | 0.0046 (7) |
C14 | 0.0288 (8) | 0.0225 (8) | 0.0230 (8) | −0.0121 (7) | −0.0017 (6) | −0.0035 (6) |
S1—O1 | 1.4249 (12) | C7—C8 | 1.380 (2) |
S1—O2 | 1.4198 (11) | C7—C12 | 1.383 (2) |
S1—O3 | 1.5887 (11) | C8—H8 | 0.9500 |
S1—C1 | 1.7797 (15) | C8—C9 | 1.393 (2) |
O3—C7 | 1.4268 (18) | C9—C10 | 1.394 (2) |
O4—N1 | 1.2195 (17) | C9—C13 | 1.505 (2) |
O5—N1 | 1.2263 (18) | C10—H10 | 0.9500 |
N1—C6 | 1.473 (2) | C10—C11 | 1.392 (2) |
C1—C2 | 1.391 (2) | C11—C12 | 1.395 (2) |
C1—C6 | 1.400 (2) | C11—C14 | 1.507 (2) |
C2—H2 | 0.9500 | C12—H12 | 0.9500 |
C2—C3 | 1.389 (2) | C13—H13A | 0.9800 |
C3—H3 | 0.9500 | C13—H13B | 0.9800 |
C3—C4 | 1.385 (3) | C13—H13C | 0.9800 |
C4—H4 | 0.9500 | C14—H14A | 0.9800 |
C4—C5 | 1.387 (2) | C14—H14B | 0.9800 |
C5—H5 | 0.9500 | C14—H14C | 0.9800 |
C5—C6 | 1.385 (2) | ||
O1—S1—O3 | 109.83 (6) | C8—C7—C12 | 123.31 (14) |
O1—S1—C1 | 106.85 (7) | C12—C7—O3 | 117.36 (13) |
O2—S1—O1 | 119.41 (7) | C7—C8—H8 | 120.8 |
O2—S1—O3 | 105.16 (6) | C7—C8—C9 | 118.42 (14) |
O2—S1—C1 | 110.43 (7) | C9—C8—H8 | 120.8 |
O3—S1—C1 | 104.16 (6) | C8—C9—C10 | 118.82 (14) |
C7—O3—S1 | 120.43 (9) | C8—C9—C13 | 120.43 (15) |
O4—N1—O5 | 124.23 (14) | C10—C9—C13 | 120.75 (15) |
O4—N1—C6 | 118.87 (12) | C9—C10—H10 | 118.9 |
O5—N1—C6 | 116.89 (13) | C11—C10—C9 | 122.27 (15) |
C2—C1—S1 | 115.24 (12) | C11—C10—H10 | 118.9 |
C2—C1—C6 | 118.36 (14) | C10—C11—C12 | 118.57 (14) |
C6—C1—S1 | 126.38 (12) | C10—C11—C14 | 120.02 (14) |
C1—C2—H2 | 119.7 | C12—C11—C14 | 121.41 (14) |
C3—C2—C1 | 120.67 (15) | C7—C12—C11 | 118.60 (14) |
C3—C2—H2 | 119.7 | C7—C12—H12 | 120.7 |
C2—C3—H3 | 119.9 | C11—C12—H12 | 120.7 |
C4—C3—C2 | 120.11 (15) | C9—C13—H13A | 109.5 |
C4—C3—H3 | 119.9 | C9—C13—H13B | 109.5 |
C3—C4—H4 | 119.9 | C9—C13—H13C | 109.5 |
C3—C4—C5 | 120.10 (15) | H13A—C13—H13B | 109.5 |
C5—C4—H4 | 119.9 | H13A—C13—H13C | 109.5 |
C4—C5—H5 | 120.2 | H13B—C13—H13C | 109.5 |
C6—C5—C4 | 119.59 (15) | C11—C14—H14A | 109.5 |
C6—C5—H5 | 120.2 | C11—C14—H14B | 109.5 |
C1—C6—N1 | 122.82 (13) | C11—C14—H14C | 109.5 |
C5—C6—N1 | 116.05 (14) | H14A—C14—H14B | 109.5 |
C5—C6—C1 | 121.13 (14) | H14A—C14—H14C | 109.5 |
C8—C7—O3 | 119.06 (13) | H14B—C14—H14C | 109.5 |
S1—O3—C7—C8 | −74.03 (15) | C1—S1—O3—C7 | −84.68 (11) |
S1—O3—C7—C12 | 111.80 (13) | C1—C2—C3—C4 | 1.8 (2) |
S1—C1—C2—C3 | 176.26 (12) | C2—C1—C6—N1 | −179.70 (14) |
S1—C1—C6—N1 | 2.0 (2) | C2—C1—C6—C5 | 0.8 (2) |
S1—C1—C6—C5 | −177.44 (12) | C2—C3—C4—C5 | 0.0 (2) |
O1—S1—O3—C7 | 29.44 (12) | C3—C4—C5—C6 | −1.3 (2) |
O1—S1—C1—C2 | 21.24 (13) | C4—C5—C6—N1 | −178.57 (13) |
O1—S1—C1—C6 | −160.46 (13) | C4—C5—C6—C1 | 0.9 (2) |
O2—S1—O3—C7 | 159.13 (10) | C6—C1—C2—C3 | −2.2 (2) |
O2—S1—C1—C2 | −110.09 (12) | C7—C8—C9—C10 | 1.6 (2) |
O2—S1—C1—C6 | 68.21 (15) | C7—C8—C9—C13 | −178.43 (14) |
O3—S1—C1—C2 | 137.46 (11) | C8—C7—C12—C11 | 0.0 (2) |
O3—S1—C1—C6 | −44.23 (14) | C8—C9—C10—C11 | −1.1 (2) |
O3—C7—C8—C9 | −174.87 (12) | C9—C10—C11—C12 | 0.0 (2) |
O3—C7—C12—C11 | 173.85 (12) | C9—C10—C11—C14 | −179.82 (14) |
O4—N1—C6—C1 | −39.7 (2) | C10—C11—C12—C7 | 0.6 (2) |
O4—N1—C6—C5 | 139.82 (14) | C12—C7—C8—C9 | −1.1 (2) |
O5—N1—C6—C1 | 141.33 (16) | C13—C9—C10—C11 | 178.94 (14) |
O5—N1—C6—C5 | −39.2 (2) | C14—C11—C12—C7 | −179.61 (13) |
D—H···A | D—H | H···A | D···A | D—H···A |
C5—H5···O1i | 0.95 | 2.56 | 3.4544 (19) | 156 |
C8—H8···O5ii | 0.95 | 2.56 | 3.468 (2) | 160 |
Symmetry codes: (i) x+1, y−1, z; (ii) x−1, y+1, z. |
Acknowledgements
The authors thank GVSU for financial support (Weldon Fund, CSCE), the NSF for a 300 MHz Jeol FT–NMR (CCLI-0087655), and Pfizer, Inc. for the donation of a Varian Inova 400 FT–NMR. The CCD-based X-ray diffractometers at Michigan State University were upgraded and/or replaced by departmental funds.
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