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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 66| Part 9| September 2010| Page o2429
https://doi.org/10.1107/S1600536810034100

2-(3-Nitro­phen­­oxy)quinoxaline

Noor Doha Hassan,a Zanariah Abdullah,a‡ Hairul Anuar Tajuddin,a Zainal A. Fairuz,a Seik Weng Nga and Edward R. T. Tiekinka*

aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com

(Received 19 August 2010; accepted 24 August 2010; online 28 August 2010)

In the title mol­ecule, C14H9N3O3, the dihedral angle between the quinoxaline and benzene rings is 77.13 (9)°. The mol­ecule is twisted about the ether–benzene O—C bond, with a C—O—C—C torsion angle of −102.8 (2)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, forming layers in the ab plane, with one nitro O atom accepting two such inter­actions. The layers stack along the c-axis direction via weak C—H⋯π inter­actions.

Related literature

For background to the fluorescence properties of compounds related to the title compound, see: Kawai et al. (2001[Kawai, M., Lee, M. J., Evans, K. O. & Norlund, T. (2001). J. Fluoresc. 11, 23-32.]); Abdullah (2005[Abdullah, Z. (2005). Int. J. Chem. Sci. 3, 9-15.]). For the structures of the polymorphic phenyl quinoxalin-2-yl ether compound, see: Hassan et al. (2008[Hassan, N. D., Tajuddin, H. A., Abdullah, Z. & Ng, S. W. (2008). Acta Cryst. E64, o1820.]); Abdullah & Ng (2008[Abdullah, Z. & Ng, S. W. (2008). Acta Cryst. E64, o2165.]).

[Scheme 1]

Experimental

Crystal data

  • C14H9N3O3

  • Mr = 267.24

  • Monoclinic, P 21

  • a = 6.0643 (6) Å

  • b = 5.3676 (5) Å

  • c = 18.2443 (17) Å

  • β = 91.780 (1)°

  • V = 593.58 (10) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.11 mm−1

  • T = 100 K

  • 0.35 × 0.25 × 0.15 mm
Data collection

  • Bruker SMART APEX CCD diffractometer

  • 5637 measured reflections

  • 1502 independent reflections

  • 1403 reflections with I > 2σ(I)

  • Rint = 0.028
Refinement

  • R[F2 > 2σ(F2)] = 0.034

  • wR(F2) = 0.093

  • S = 1.04

  • 1501 reflections

  • 181 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.22 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C3–C8 ring.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C10—H10⋯O2i 0.95 2.34 3.282 (3) 173
C12—H12⋯O2ii 0.95 2.44 3.159 (2) 133
C5—H5⋯Cg1iii 0.95 2.99 3.696 (2) 133
Symmetry codes: (i) x+1, y-1, z; (ii) [-x+1, y-{\script{1\over 2}}, -z+1]; (iii) [-x+2, y-{\script{1\over 2}}, -z].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and DIAMOND (Brandenburg, 2006[Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: publCIF (Westrip, 2010[Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810034100/hb5615sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810034100/hb5615Isup2.hkl

checkCIF report


Comment top

Quinoxaline derivatives show interesting fluorescence properties (Kawai et al. 2001; Abdullah, 2005) and this observation prompted the synthesis and characterization of the title compound, (I).

The molecule in (I), Fig. 1, is bent as the quinoxaline ring [r.m.s. deviation = 0.025 Å] forms a dihedral angle of 77.13 (9) ° with the benzene molecule. The twist in the molecule is seen in the value of the C1–O1–C9–C14 torsion angle of -102.8 (2) °. Overall the conformation of the molecule matches those found in the polymorphic phenyl quinoxalin-2-yl ether compound (Hassan et al., 2008; Abdullah & Ng, 2008). In (I), the nitro group is slightly twisted out of the plane of the benzene ring to which it is bonded as seen in the O2–N3–C13–C12 torsion angle of 12.6 (3) °.

The bifurcated nitro-O2 atom is pivotal in the crystal packing, forming two close C–H···O interactions, Table 1, leading to the formation of layers in the ab plane, Fig. 2. These stack along the c axis, being connected by C–H···π interactions, Fig. 3.

Related literature top

For background to the fluorescence properties of compounds related to the title compound, see: Kawai et al. (2001); Abdullah (2005). For the structures of the polymorphic phenyl quinoxalin-2-yl ether compound, see: Hassan et al. (2008); Abdullah & Ng (2008).

Experimental top

3-Nitrophenol (5 mmol) was dissolved in tetrahydrofuran (100 ml) to which was added 2-chloroquinoxaline with a stoichiometric amount of NaOH. The solution was refluxed for 4 h. The mixture was extracted using 5% sodium hydroxide solution (5 ml), then chloroform (20 ml), washed with distilled water (30 ml), and dried over anhydrous sodium hydroxide. Evaporation of the solvent gave a red solid and recrystallization was from its ethanol solution to yield red prisms of (I).

Refinement top

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 Å) and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Uequiv(C). In the absence of significant anomalous scattering effects, 1199 Friedel pairs were averaged in the final refinement. In the final refinement a low angle reflection evidently effected by the beam stop were omitted, i.e. 0 0 1.

Structure description top

Quinoxaline derivatives show interesting fluorescence properties (Kawai et al. 2001; Abdullah, 2005) and this observation prompted the synthesis and characterization of the title compound, (I).

The molecule in (I), Fig. 1, is bent as the quinoxaline ring [r.m.s. deviation = 0.025 Å] forms a dihedral angle of 77.13 (9) ° with the benzene molecule. The twist in the molecule is seen in the value of the C1–O1–C9–C14 torsion angle of -102.8 (2) °. Overall the conformation of the molecule matches those found in the polymorphic phenyl quinoxalin-2-yl ether compound (Hassan et al., 2008; Abdullah & Ng, 2008). In (I), the nitro group is slightly twisted out of the plane of the benzene ring to which it is bonded as seen in the O2–N3–C13–C12 torsion angle of 12.6 (3) °.

The bifurcated nitro-O2 atom is pivotal in the crystal packing, forming two close C–H···O interactions, Table 1, leading to the formation of layers in the ab plane, Fig. 2. These stack along the c axis, being connected by C–H···π interactions, Fig. 3.

For background to the fluorescence properties of compounds related to the title compound, see: Kawai et al. (2001); Abdullah (2005). For the structures of the polymorphic phenyl quinoxalin-2-yl ether compound, see: Hassan et al. (2008); Abdullah & Ng (2008).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 50% probability level.
[Figure 2] Fig. 2. Supramolecular layer in the ab plane mediated by C–H···O interactions, shown as orange dashed lines, in (I).
[Figure 3] Fig. 3. Unit-cell contents shown in projection down the a axis in (I), highlighting the stacking of layers along the c direction. The C–H···O and C–H···π interactions are shown as orange and purple dashed lines, respectively.
2-(3-Nitrophenoxy)quinoxaline top
Crystal data top
C14H9N3O3F(000) = 276
Mr = 267.24Dx = 1.495 Mg m−3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 2560 reflections
a = 6.0643 (6) Åθ = 2.2–28.3°
b = 5.3676 (5) ŵ = 0.11 mm−1
c = 18.2443 (17) ÅT = 100 K
β = 91.780 (1)°Prism, red
V = 593.58 (10) Å30.35 × 0.25 × 0.15 mm
Z = 2
Data collection top
Bruker SMART APEX CCD
diffractometer		1403 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.028
Graphite monochromatorθmax = 27.5°, θmin = 1.1°
ω scansh = −7→7
5637 measured reflectionsk = −6→6
1502 independent reflectionsl = −23→23
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.034H-atom parameters constrained
wR(F2) = 0.093 w = 1/[σ2(Fo2) + (0.0584P)2 + 0.098P]
where P = (Fo2 + 2Fc2)/3
S = 1.04(Δ/σ)max < 0.001
1501 reflectionsΔρmax = 0.24 e Å−3
181 parametersΔρmin = −0.22 e Å−3
1 restraintAbsolute structure: nd
Primary atom site location: structure-invariant direct methods
Crystal data top
C14H9N3O3V = 593.58 (10) Å3
Mr = 267.24Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.0643 (6) ŵ = 0.11 mm−1
b = 5.3676 (5) ÅT = 100 K
c = 18.2443 (17) Å0.35 × 0.25 × 0.15 mm
β = 91.780 (1)°
Data collection top
Bruker SMART APEX CCD
diffractometer		1403 reflections with I > 2σ(I)
5637 measured reflectionsRint = 0.028
1502 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0341 restraint
wR(F2) = 0.093H-atom parameters constrained
S = 1.04Δρmax = 0.24 e Å−3
1501 reflectionsΔρmin = −0.22 e Å−3
181 parametersAbsolute structure: nd
Special details top

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 > 2σ(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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O11.2692 (2)0.5001 (3)0.29144 (7)0.0241 (3)
O20.4391 (2)0.8540 (4)0.41409 (8)0.0309 (4)
O30.5748 (2)0.9758 (3)0.31197 (9)0.0309 (4)
N11.1038 (2)0.1916 (4)0.22012 (8)0.0203 (4)
N21.4817 (3)0.2107 (4)0.13226 (9)0.0242 (4)
N30.5762 (3)0.8419 (4)0.36598 (9)0.0224 (4)
C11.2685 (3)0.3411 (4)0.23292 (10)0.0201 (4)
C21.4591 (3)0.3556 (4)0.18864 (11)0.0229 (4)
H21.57130.47350.20070.028*
C31.3147 (3)0.0427 (4)0.11749 (10)0.0212 (4)
C41.3319 (3)−0.1261 (5)0.05877 (11)0.0261 (5)
H41.4576−0.12160.02900.031*
C51.1678 (3)−0.2970 (5)0.04435 (11)0.0281 (5)
H51.1817−0.41130.00500.034*
C60.9785 (3)−0.3042 (5)0.08741 (11)0.0268 (5)
H60.8666−0.42430.07740.032*
C70.9563 (3)−0.1377 (5)0.14384 (10)0.0227 (4)
H70.8263−0.13930.17160.027*
C81.1248 (3)0.0355 (4)0.16091 (10)0.0194 (4)
C91.0867 (3)0.4856 (4)0.33663 (10)0.0198 (4)
C101.0743 (3)0.2998 (4)0.38865 (11)0.0228 (4)
H101.18660.17690.39300.027*
C110.8952 (3)0.2945 (4)0.43471 (11)0.0229 (4)
H110.88670.16900.47120.027*
C120.7295 (3)0.4715 (4)0.42751 (10)0.0200 (4)
H120.60510.46710.45790.024*
C130.7504 (3)0.6547 (4)0.37477 (10)0.0181 (4)
C140.9282 (3)0.6693 (4)0.32869 (10)0.0193 (4)
H140.94020.79890.29360.023*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0166 (6)0.0277 (8)0.0286 (7)−0.0011 (6)0.0085 (5)−0.0071 (7)
O20.0254 (7)0.0371 (9)0.0307 (8)0.0124 (7)0.0081 (6)−0.0029 (7)
O30.0265 (7)0.0290 (9)0.0372 (8)0.0069 (7)0.0003 (6)0.0113 (7)
N10.0184 (7)0.0230 (9)0.0198 (7)0.0034 (7)0.0028 (6)0.0005 (7)
N20.0211 (8)0.0274 (10)0.0244 (8)0.0027 (7)0.0074 (6)0.0035 (8)
N30.0192 (7)0.0220 (9)0.0260 (8)0.0050 (7)0.0011 (6)−0.0017 (8)
C10.0166 (8)0.0204 (10)0.0233 (9)0.0038 (8)0.0033 (7)0.0004 (9)
C20.0188 (9)0.0241 (11)0.0262 (10)0.0003 (9)0.0056 (7)0.0011 (9)
C30.0222 (9)0.0231 (11)0.0183 (9)0.0061 (8)0.0035 (7)0.0025 (8)
C40.0285 (10)0.0294 (12)0.0208 (9)0.0081 (10)0.0062 (7)0.0013 (9)
C50.0327 (11)0.0308 (12)0.0210 (9)0.0080 (10)0.0006 (8)−0.0042 (9)
C60.0286 (10)0.0272 (12)0.0245 (10)0.0019 (9)−0.0024 (8)−0.0005 (10)
C70.0227 (9)0.0262 (11)0.0193 (9)0.0010 (9)0.0017 (7)0.0013 (9)
C80.0196 (8)0.0211 (11)0.0177 (8)0.0045 (8)0.0018 (6)0.0026 (8)
C90.0134 (8)0.0234 (10)0.0228 (9)−0.0010 (8)0.0041 (6)−0.0058 (9)
C100.0182 (9)0.0205 (11)0.0296 (10)0.0048 (8)−0.0001 (7)−0.0018 (8)
C110.0244 (9)0.0202 (11)0.0240 (10)0.0004 (8)0.0016 (7)0.0023 (8)
C120.0176 (8)0.0228 (11)0.0198 (9)0.0003 (8)0.0032 (6)−0.0015 (8)
C130.0167 (8)0.0181 (10)0.0196 (8)0.0025 (7)0.0003 (6)−0.0032 (8)
C140.0193 (9)0.0202 (10)0.0186 (8)−0.0001 (8)0.0014 (6)−0.0007 (8)
Geometric parameters (Å, º) top
O1—C11.367 (2)C5—H50.9500
O1—C91.402 (2)C6—C71.373 (3)
O2—N31.229 (2)C6—H60.9500
O3—N31.219 (2)C7—C81.410 (3)
N1—C11.297 (3)C7—H70.9500
N1—C81.376 (3)C9—C101.380 (3)
N2—C21.300 (3)C9—C141.382 (3)
N2—C31.376 (3)C10—C111.394 (3)
N3—C131.463 (2)C10—H100.9500
C1—C21.433 (2)C11—C121.386 (3)
C2—H20.9500C11—H110.9500
C3—C41.409 (3)C12—C131.384 (3)
C3—C81.419 (2)C12—H120.9500
C4—C51.373 (3)C13—C141.390 (3)
C4—H40.9500C14—H140.9500
C5—C61.411 (3)
C1—O1—C9116.22 (15)C6—C7—C8120.51 (18)
C1—N1—C8115.37 (16)C6—C7—H7119.7
C2—N2—C3116.86 (16)C8—C7—H7119.7
O3—N3—O2123.90 (18)N1—C8—C7119.41 (16)
O3—N3—C13118.70 (16)N1—C8—C3121.23 (17)
O2—N3—C13117.40 (17)C7—C8—C3119.35 (18)
N1—C1—O1120.68 (16)C10—C9—C14122.35 (16)
N1—C1—C2124.22 (18)C10—C9—O1120.34 (17)
O1—C1—C2115.10 (17)C14—C9—O1117.25 (18)
N2—C2—C1121.36 (19)C9—C10—C11119.30 (18)
N2—C2—H2119.3C9—C10—H10120.3
C1—C2—H2119.3C11—C10—H10120.3
N2—C3—C4119.93 (17)C12—C11—C10120.34 (19)
N2—C3—C8120.91 (17)C12—C11—H11119.8
C4—C3—C8119.17 (18)C10—C11—H11119.8
C5—C4—C3120.34 (18)C13—C12—C11118.07 (17)
C5—C4—H4119.8C13—C12—H12121.0
C3—C4—H4119.8C11—C12—H12121.0
C4—C5—C6120.6 (2)C12—C13—C14123.39 (18)
C4—C5—H5119.7C12—C13—N3118.84 (16)
C6—C5—H5119.7C14—C13—N3117.76 (18)
C7—C6—C5120.0 (2)C9—C14—C13116.51 (18)
C7—C6—H6120.0C9—C14—H14121.7
C5—C6—H6120.0C13—C14—H14121.7
C8—N1—C1—O1−178.20 (17)C4—C3—C8—N1178.05 (18)
C8—N1—C1—C22.1 (3)N2—C3—C8—C7179.52 (18)
C9—O1—C1—N11.7 (3)C4—C3—C8—C7−0.8 (3)
C9—O1—C1—C2−178.60 (17)C1—O1—C9—C1079.9 (2)
C3—N2—C2—C1−0.3 (3)C1—O1—C9—C14−102.8 (2)
N1—C1—C2—N2−1.8 (3)C14—C9—C10—C110.5 (3)
O1—C1—C2—N2178.42 (18)O1—C9—C10—C11177.72 (17)
C2—N2—C3—C4−177.78 (19)C9—C10—C11—C121.1 (3)
C2—N2—C3—C81.9 (3)C10—C11—C12—C13−1.5 (3)
N2—C3—C4—C5178.96 (19)C11—C12—C13—C140.3 (3)
C8—C3—C4—C5−0.7 (3)C11—C12—C13—N3179.51 (17)
C3—C4—C5—C60.8 (3)O3—N3—C13—C12−167.50 (18)
C4—C5—C6—C70.7 (3)O2—N3—C13—C1212.5 (3)
C5—C6—C7—C8−2.2 (3)O3—N3—C13—C1411.8 (3)
C1—N1—C8—C7178.47 (18)O2—N3—C13—C14−168.20 (18)
C1—N1—C8—C3−0.4 (3)C10—C9—C14—C13−1.7 (3)
C6—C7—C8—N1−176.59 (19)O1—C9—C14—C13−178.92 (16)
C6—C7—C8—C32.3 (3)C12—C13—C14—C91.3 (3)
N2—C3—C8—N1−1.6 (3)N3—C13—C14—C9−177.99 (16)
Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C3–C8 ring.
D—H···AD—HH···AD···AD—H···A
C10—H10···O2i0.952.343.282 (3)173
C12—H12···O2ii0.952.443.159 (2)133
C5—H5···Cg1iii0.952.993.696 (2)133
Symmetry codes: (i) x+1, y−1, z; (ii) −x+1, y−1/2, −z+1; (iii) −x+2, y−1/2, −z.

Experimental details

Crystal data
Chemical formulaC14H9N3O3
Mr267.24
Crystal system, space groupMonoclinic, P21
Temperature (K)100
a, b, c (Å)6.0643 (6), 5.3676 (5), 18.2443 (17)
β (°) 91.780 (1)
V (Å3)593.58 (10)
Z2
Radiation typeMo Kα
µ (mm−1)0.11
Crystal size (mm)0.35 × 0.25 × 0.15
Data collection
DiffractometerBruker SMART APEX CCD
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		5637, 1502, 1403
Rint0.028
(sin θ/λ)max (Å−1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.034, 0.093, 1.04
No. of reflections1501
No. of parameters181
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.24, −0.22
Absolute structureNd

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top
Cg1 is the centroid of the C3–C8 ring.
D—H···AD—HH···AD···AD—H···A
C10—H10···O2i0.952.343.282 (3)173
C12—H12···O2ii0.952.443.159 (2)133
C5—H5···Cg1iii0.952.993.696 (2)133
Symmetry codes: (i) x+1, y−1, z; (ii) −x+1, y−1/2, −z+1; (iii) −x+2, y−1/2, −z.
 

Footnotes

‡Additional correspondence author, e-mail: zana@um.edu.my.

Acknowledgements

AZ thanks the Ministry of Higher Education for research grants (FP047/2008 C, RG080/09AFR and RG027/09AFR). The authors are also grateful to the University of Malaya for support of the crystallographic facility.

References

First citationAbdullah, Z. (2005). Int. J. Chem. Sci. 3, 9–15.  CAS Google Scholar
 First citationAbdullah, Z. & Ng, S. W. (2008). Acta Cryst. E64, o2165.  Web of Science CSD CrossRef IUCr Journals Google Scholar
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ISSN: 2056-9890
Volume 66| Part 9| September 2010| Page o2429
https://doi.org/10.1107/S1600536810034100
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