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Acta Cryst. (2013). E69, o1808    [ doi:10.1107/S1600536813031309 ]

2,5-Di­meth­oxy­benzo­nitrile

B. Bugenhagen, Y. Al Jasem and T. Thiemann

CCDC reference: 972097

Abstract top

In the title mol­ecule, C9H9NO2, the non-H atoms are essentially coplanar with a maximum deviation of 0.027 (2) Å for the C atom of one of the methyl groups. In the crystal, the mol­ecules are arranged into centrosymmetric pairs via pairs of C-H...O and C-H...N inter­actions whereas [pi]-[pi] stacking inter­actions between the benzene rings [centroid-centroid distance 3.91001 (15) Å] organize them into polymeric strands propagating along the a-axis direction. There is a step of 0.644 (2) Å between the two planar parts of the centrosymmetric pair. In neighboring strands related by the n-glide operation, the aromatic rings are tilted by 29.08 (2)°.

Comment top

The aromatic ring (C1—C6) of the title compound is almost coplanar with non-H atoms of all substituents, with torsion angles of 3.2 (2)°, 2.5 (2)° and 178.7 (1)° for the methoxy group (C3—C2—O1—C8), for the methoxy group (C4—C5—O2—C9) and for the nitrile group (C5—C6—C1—C7), respectively. With the length of 1.1492 (19) Å, the triple bond of the nitrile group (CN) is at the higher end of the acceptable range of cyano bond lengths (Buschmann et al., 1995; Zanotti et al., 1980), but longer than in comparable alkoxy-substituted benzonitriles (Zabinski et al., 2007). The molecules of the title compound arrange themselves in pairs through C8–H8B···O1 and C8–H8B···N1 interactions (Table 1, Fig. 2). In one pair, the average plane of the aromatic ring (C1—C6) of one molecule has an off-set of 0.644 (2) Å to the respective plane in the other molecule. The stacked centrosymmetric dimers form strands propagating along the a axis. Each pair in one strand forms four close contacts C9—H9B···N1 (Table 1) with four pairs of the four neighboring strands (Figure 3). The average plane of the aromatic ring (C1—C6) of a molecule in one strand forms an angle of 29.08 (2)° with the respective average plane of another molecule in the neighboring strand, with the molecules linked by C9—H9B···N1 close contact.

Related literature top

For the use of the title compound as a key reagent in the synthesis of pharmaceutically active heterocycles, see: Bergeron et al. (2006); Delgado et al. (1987). For another method of preparation of the title compound, see: Ushijima et al. (2012). For the crystal structures of aromatic nitriles, see: Buschmann et al. (1995); Zabinski et al. (2007); Zanotti et al. (1980).

Experimental top

To triphenylphosphine (870 mg, 3.3 mmol) in dry CH2Cl2 (10 ml) was added bromotrichloromethane (650 mg, 3.3 mmol), and the resulting mixture was stirred at rt for 20 min, during which the solution turned from yellow to red-brownish in color. Thereafter, 2,5-dimethoxybenzaldoxime (552 mg, 3.05 mmol) was added. The reaction mixture was kept under reflux for 25 min. Then, triphenylphosphine (870 mg, 3.3 mmol) was added, and the mixture stirred for 8 h at reflux. The cooled reaction mixture was concentrated in vacuo and subjected directly to column chromatography on silica gel (CH2Cl2 – hexane 5: 1) to give the title compound (195 mg, 39%) as colorless needles; m.p. 360 - 361 K (Lit. 354 - 358 K; Ushijima et al., 2012); nmax (KBr/cm-1) 2224 (CN), 1582, 1508, 1420, 1287, 1237, 1120, 1039, 879, 815, 753, 704, 488; dH (400 MHz, CDCl3) 3.77 (3H, s, OCH3), 3.87 (3H, s, OCH3), 6.89 (1H, d, 3J = 8.8 Hz), 7.04 (1H, d, 4J = 2.8 Hz), 7.07 (1H, dd, 3J = 8.8 Hz, 4J = 2.8 Hz); dC (100.5 MHz, CDCl3) 55.9 (OCH3), 56.4 (OCH3), 101.7 (Cquat), 112.6 (CH), 116.4 (Cquat), 117.5 (CH), 120.8 (CH), 153.1 (Cquat), 153.7 (Cquat); MS (EI, 70 eV) m/z (%) 163 (M+, 100).

Refinement top

All carbon-bound hydrogen atoms were placed in calculated positions with C—H distances of 0.95 - 0.98 Å and refined as riding with Uiso(H) =xUeq(C), where x = 1.5 for methyl and x = 1.2 for all other H-atoms.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2013); cell refinement: CrysAlis PRO (Agilent, 2013); data reduction: CrysAlis PRO (Agilent, 2013); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) within OLEX2 (Dolomanov et al., 2009); molecular graphics: PLATON (Spek, 2009); Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. A view of the title molecule with displacement ellipsoids shown at the 50% probability level.
[Figure 2] Fig. 2. Intermolecular interactions between molecules of the title compound. [Symmetry codes: i: x,y,z; ii: 3 - x,2 - y,1 - z; iii: 2.5 - x,-1/2 + y,1/2 - z; iv: -1/2 + x,1.5 - y,1/2 + z]
[Figure 3] Fig. 3. The crystal packing diagram showing the C—H···O and C—H···N intermolecular interactions between molecules within pairs (green colored) and between molecules in different strands (blue colored).
2,5-Dimethoxybenzonitrile top
Crystal data top
C9H9NO2Dx = 1.373 Mg m3
Mr = 163.17Melting point = 360–361 K
Monoclinic, P21/nMo Kα radiation, λ = 0.7107 Å
a = 3.91001 (15) ÅCell parameters from 1290 reflections
b = 11.3347 (4) Åθ = 3.6–32.0°
c = 17.8432 (6) ŵ = 0.10 mm1
β = 93.400 (3)°T = 100 K
V = 789.40 (5) Å3Block, colourless
Z = 40.60 × 0.25 × 0.23 mm
F(000) = 344
Data collection top
Agilent SuperNova (Dual, Cu at zero, Atlas)
diffractometer
1785 independent reflections
Radiation source: SuperNova (Mo) X-ray Source1374 reflections with I > 2σ(I)
Mirror monochromatorRint = 0.026
Detector resolution: 10.4127 pixels mm-1θmax = 27.5°, θmin = 3.6°
ω scansh = 54
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)
k = 914
Tmin = 0.899, Tmax = 1.000l = 2123
3225 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.044H-atom parameters constrained
wR(F2) = 0.116 w = 1/[σ2(Fo2) + (0.048P)2 + 0.110P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
1785 reflectionsΔρmax = 0.21 e Å3
111 parametersΔρmin = 0.24 e Å3
0 restraints
Crystal data top
C9H9NO2V = 789.40 (5) Å3
Mr = 163.17Z = 4
Monoclinic, P21/nMo Kα radiation
a = 3.91001 (15) ŵ = 0.10 mm1
b = 11.3347 (4) ÅT = 100 K
c = 17.8432 (6) Å0.60 × 0.25 × 0.23 mm
β = 93.400 (3)°
Data collection top
Agilent SuperNova (Dual, Cu at zero, Atlas)
diffractometer
1785 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2013)
1374 reflections with I > 2σ(I)
Tmin = 0.899, Tmax = 1.000Rint = 0.026
3225 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.116H-atom parameters constrained
S = 1.06Δρmax = 0.21 e Å3
1785 reflectionsΔρmin = 0.24 e Å3
111 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C11.1608 (4)0.84580 (13)0.32618 (8)0.0170 (3)
C21.1137 (4)0.96337 (13)0.34798 (7)0.0170 (3)
C30.9434 (4)1.03957 (13)0.29791 (8)0.0178 (3)
C40.8238 (4)1.00071 (13)0.22693 (8)0.0180 (3)
C50.8723 (4)0.88435 (13)0.20555 (8)0.0166 (3)
C61.0425 (4)0.80699 (13)0.25538 (7)0.0178 (3)
C71.3310 (4)0.76401 (14)0.37753 (8)0.0193 (3)
C81.1889 (4)1.11088 (14)0.44323 (8)0.0214 (4)
C90.5943 (4)0.91476 (14)0.08362 (8)0.0227 (4)
H30.90771.11920.31200.021*
H40.70861.05410.19300.022*
H61.07820.72740.24100.021*
H8A1.29631.16680.40990.032*
H8B1.28951.12020.49450.032*
H8C0.94211.12640.44250.032*
H9A0.53170.87080.03750.034*
H9B0.74980.97930.07230.034*
H9C0.38720.94720.10410.034*
N11.4646 (4)0.69750 (12)0.41812 (7)0.0264 (3)
O11.2456 (3)0.99244 (9)0.41788 (5)0.0202 (3)
O20.7618 (3)0.83694 (9)0.13775 (5)0.0219 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0161 (7)0.0162 (8)0.0189 (7)0.0002 (6)0.0038 (5)0.0027 (6)
C20.0161 (8)0.0185 (8)0.0165 (7)0.0017 (6)0.0025 (5)0.0012 (6)
C30.0184 (8)0.0147 (7)0.0204 (7)0.0000 (6)0.0026 (6)0.0003 (6)
C40.0178 (8)0.0170 (7)0.0194 (7)0.0008 (6)0.0024 (6)0.0039 (6)
C50.0157 (7)0.0176 (8)0.0165 (7)0.0028 (6)0.0020 (5)0.0008 (6)
C60.0169 (8)0.0164 (7)0.0206 (7)0.0007 (6)0.0041 (6)0.0001 (6)
C70.0210 (8)0.0174 (8)0.0196 (7)0.0005 (7)0.0030 (6)0.0018 (6)
C80.0260 (9)0.0184 (8)0.0196 (7)0.0012 (7)0.0007 (6)0.0027 (6)
C90.0256 (9)0.0229 (8)0.0189 (7)0.0011 (7)0.0029 (6)0.0031 (6)
N10.0334 (9)0.0212 (7)0.0243 (7)0.0046 (6)0.0004 (6)0.0003 (6)
O10.0258 (6)0.0172 (6)0.0171 (5)0.0027 (5)0.0029 (4)0.0009 (4)
O20.0281 (6)0.0196 (6)0.0174 (5)0.0000 (5)0.0033 (4)0.0002 (4)
Geometric parameters (Å, º) top
C2—C11.404 (2)C8—H8C0.9800
C2—C31.384 (2)C8—H8B0.9800
C3—C41.395 (2)C8—H8A0.9800
C3—H30.9500C9—H9C0.9800
C4—H40.9500C9—H9B0.9800
C5—C41.389 (2)C9—H9A0.9800
C5—C61.390 (2)O1—C81.4381 (18)
C6—C11.391 (2)O1—C21.3616 (17)
C6—H60.9500O2—C91.4370 (18)
C7—N11.1492 (19)O2—C51.3700 (17)
C7—C11.439 (2)
C1—C6—H6119.9H8A—C8—H8B109.5
C2—C1—C7119.92 (13)H8B—C8—H8C109.5
C2—C3—C4120.75 (14)H9A—C9—H9C109.5
C2—C3—H3119.6H9A—C9—H9B109.5
C2—O1—C8117.18 (11)H9B—C9—H9C109.5
C3—C4—H4119.8N1—C7—C1179.12 (16)
C3—C2—C1118.65 (13)O1—C8—H8C109.5
C4—C3—H3119.6O1—C8—H8B109.5
C4—C5—C6119.42 (13)O1—C8—H8A109.5
C5—C4—H4119.8O1—C2—C1115.77 (13)
C5—C4—C3120.35 (14)O1—C2—C3125.57 (14)
C5—C6—C1120.16 (14)O2—C9—H9C109.5
C5—C6—H6119.9O2—C9—H9B109.5
C5—O2—C9117.39 (11)O2—C9—H9A109.5
C6—C1—C7119.42 (13)O2—C5—C4125.03 (13)
C6—C1—C2120.67 (14)O2—C5—C6115.55 (13)
H8A—C8—H8C109.5
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8B···O1i0.982.653.428 (2)136
C8—H8B···N1i0.982.733.504 (2)136
C9—H9B···N1ii0.982.713.640 (2)158
Symmetry codes: (i) x+3, y+2, z+1; (ii) x+5/2, y+1/2, z+1/2.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8B···O1i0.982.653.428 (2)136
C8—H8B···N1i0.982.733.504 (2)136
C9—H9B···N1ii0.982.713.640 (2)158
Symmetry codes: (i) x+3, y+2, z+1; (ii) x+5/2, y+1/2, z+1/2.
 
Acknowledgements top

no acknowledgements