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ISSN: 2056-9890

11H-Indeno­[1,2-b]quinoxalin-11-one

aSchool of Industrial Technology, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
*Correspondence e-mail: hkfun@usm.my

(Received 22 May 2010; accepted 22 May 2010; online 29 May 2010)

In the title compound, C15H8N2O, the fused ring system is approximately planar, with a maximum deviation of 0.039 (1) Å. In the crystal, weak inter­molecular C—H⋯O inter­actions help to establish the packing.

Related literature

For applications of and background to indeno­quinoxaline, see: Gazit et al. (1996[Gazit, A., App, H., Mc Mahon, G., Chen, J., Levitzki, A. & Bohmer, F. D. (1996). J. Med. Chem. 39, 2170-2177.]); Sehlstedt et al. (1998[Sehlstedt, U., Aich, P., Bergman, J., Vallberg, E. I., Norden, B. & Graslund, A. (1998). J. Mol. Biol. 278, 31-56.]). For a related structure, see: Leslie et al. (1993[Leslie, W. D., José, D. & Andrew, C. R. (1993). Tetrahedron, 49, 9823-9828.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C15H8N2O

  • Mr = 232.23

  • Orthorhombic, P c a 21

  • a = 23.688 (3) Å

  • b = 3.7862 (5) Å

  • c = 11.5730 (16) Å

  • V = 1038.0 (2) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.65 × 0.17 × 0.09 mm

Data collection
  • Bruker APEXII DUO CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.940, Tmax = 0.991

  • 8012 measured reflections

  • 2004 independent reflections

  • 1879 reflections with I > 2σ(I)

  • Rint = 0.031

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.096

  • S = 1.05

  • 2004 reflections

  • 195 parameters

  • 1 restraint

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.35 e Å−3

  • Δρmin = −0.23 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3A⋯O1i 0.96 (2) 2.55 (2) 3.401 (2) 148.3 (19)
C9—H9A⋯O1ii 0.97 (3) 2.49 (3) 3.2458 (18) 134.0 (18)
Symmetry codes: (i) [-x+1, -y+1, z-{\script{1\over 2}}]; (ii) [-x+{\script{1\over 2}}, y-1, z-{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Indenoquinoxaline derivatives are important classes of nitrogen containing heterocycles and they constitute useful intermediates in organic synthesis (Gazit et al., 1996). They have been reported for their applications in dyes and have also been used as building blocks for the synthesis of organic semiconductors. More interestingly, research has revealed that these compounds exhibit diverse medicinal functions such as antimetabolism and antitubercular properties (Sehlstedt et al., 1998). In view of the biological importance of indenoquinoxalines, we report here the crystal structure of the title compound, (I).

The molecule of indeno[1,2-b]quinoxalin-11-one (Fig. 1) is approximately planar with maximum deviation of 0.039 (1) Å for atom C14. It contains three ring systems, viz., indene (C7–C15), pyrazine (N1/N2/C6–C7/C1/C15) and benzene (C1–C6). The C–N bond distances and C—N—C angles are C15—N1 = 1.3070 (17) Å, C1—N1 = 1.3793 (18) Å, C7—N2 = 1.3142 (17) Å, C6—N2 = 1.3800 (17) Å, C15—N1—C1 = 113.99 (12)° and C7—N2—C6 = 114.00 (12)°. These values agree with those reported in the related structure of 11H-indeno[1,2-b]quinoxalin-11-ones (Leslie et al., 1993). The pyrazine (N1/N2/C6–C7/C1/C15) ring makes dihedral angles of 0.48 (5)° and 1.34 (6)° with the indene (C7–C15) ring and the benzene (C1–C6) ring, respectively. The dihedral angle between the indene (C7–C15) ring and benzene (C1–C6) ring is 0.88 (6)°.

In the crystal structure, molecules are linked by weak intermolecular C3—H3A···O1 and C9—H9A···O1 hydrogen bonds (Table 1) interactions which help to stabilize the crystal structure.

Related literature top

For applications of and background to indenoquinoxaline, see: Gazit et al. (1996); Sehlstedt et al. (1998). For a related structure, see: Leslie et al. (1993). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

The title compound, has been synthesized by two routes: a mixture of ninhydrin (1.78 g) and o-phenylenediamine (1.08 g) in molar ratio 1:1 were [a] stirred in distilled water for 15 minutes and [b] refluxed in THF for 1 hour in presence of HCl. Both these mixtures were separately dried on rota-vapor at low pressure and then crystallized from chloroform-n-hexane (1:1) to give yellowish needles of (I).

Refinement top

Anomalous dispersion was negligible and 1465 Friedel pairs were merged for the final refinement. All the H atoms were located in a difference Fourier map and allowed to refine freely [C—H = 0.96 (2)–1.00 (2) Å].

Structure description top

Indenoquinoxaline derivatives are important classes of nitrogen containing heterocycles and they constitute useful intermediates in organic synthesis (Gazit et al., 1996). They have been reported for their applications in dyes and have also been used as building blocks for the synthesis of organic semiconductors. More interestingly, research has revealed that these compounds exhibit diverse medicinal functions such as antimetabolism and antitubercular properties (Sehlstedt et al., 1998). In view of the biological importance of indenoquinoxalines, we report here the crystal structure of the title compound, (I).

The molecule of indeno[1,2-b]quinoxalin-11-one (Fig. 1) is approximately planar with maximum deviation of 0.039 (1) Å for atom C14. It contains three ring systems, viz., indene (C7–C15), pyrazine (N1/N2/C6–C7/C1/C15) and benzene (C1–C6). The C–N bond distances and C—N—C angles are C15—N1 = 1.3070 (17) Å, C1—N1 = 1.3793 (18) Å, C7—N2 = 1.3142 (17) Å, C6—N2 = 1.3800 (17) Å, C15—N1—C1 = 113.99 (12)° and C7—N2—C6 = 114.00 (12)°. These values agree with those reported in the related structure of 11H-indeno[1,2-b]quinoxalin-11-ones (Leslie et al., 1993). The pyrazine (N1/N2/C6–C7/C1/C15) ring makes dihedral angles of 0.48 (5)° and 1.34 (6)° with the indene (C7–C15) ring and the benzene (C1–C6) ring, respectively. The dihedral angle between the indene (C7–C15) ring and benzene (C1–C6) ring is 0.88 (6)°.

In the crystal structure, molecules are linked by weak intermolecular C3—H3A···O1 and C9—H9A···O1 hydrogen bonds (Table 1) interactions which help to stabilize the crystal structure.

For applications of and background to indenoquinoxaline, see: Gazit et al. (1996); Sehlstedt et al. (1998). For a related structure, see: Leslie et al. (1993). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of (I), showing 50% probability displacement ellipsoids.
[Figure 2] Fig. 2. The crystal packing of (I), showing the hydrogen-bond (dashed lines) network.
11H-Indeno[1,2-b]quinoxalin-11-one top
Crystal data top
C15H8N2OF(000) = 480
Mr = 232.23Dx = 1.486 Mg m3
Orthorhombic, Pca21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2c -2acCell parameters from 3067 reflections
a = 23.688 (3) Åθ = 3.4–32.7°
b = 3.7862 (5) ŵ = 0.10 mm1
c = 11.5730 (16) ÅT = 100 K
V = 1038.0 (2) Å3Needle, yellow
Z = 40.65 × 0.17 × 0.09 mm
Data collection top
Bruker APEXII DUO CCD
diffractometer
2004 independent reflections
Radiation source: fine-focus sealed tube1879 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.031
φ and ω scansθmax = 32.9°, θmin = 3.4°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 3435
Tmin = 0.940, Tmax = 0.991k = 55
8012 measured reflectionsl = 1714
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.096H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.0723P)2]
where P = (Fo2 + 2Fc2)/3
2004 reflections(Δ/σ)max < 0.001
195 parametersΔρmax = 0.35 e Å3
1 restraintΔρmin = 0.23 e Å3
Crystal data top
C15H8N2OV = 1038.0 (2) Å3
Mr = 232.23Z = 4
Orthorhombic, Pca21Mo Kα radiation
a = 23.688 (3) ŵ = 0.10 mm1
b = 3.7862 (5) ÅT = 100 K
c = 11.5730 (16) Å0.65 × 0.17 × 0.09 mm
Data collection top
Bruker APEXII DUO CCD
diffractometer
2004 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
1879 reflections with I > 2σ(I)
Tmin = 0.940, Tmax = 0.991Rint = 0.031
8012 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0361 restraint
wR(F2) = 0.096H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.35 e Å3
2004 reflectionsΔρmin = 0.23 e Å3
195 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
O10.33655 (5)0.7879 (3)1.04339 (10)0.0172 (2)
N10.42154 (5)0.4986 (3)0.87194 (11)0.0133 (2)
N20.35873 (5)0.1857 (3)0.68337 (10)0.0133 (2)
C10.44805 (5)0.3540 (4)0.77697 (12)0.0124 (2)
C20.50791 (6)0.3630 (4)0.77183 (14)0.0159 (2)
C30.53554 (6)0.2296 (4)0.67669 (15)0.0181 (3)
C40.50483 (6)0.0792 (4)0.58433 (14)0.0178 (3)
C50.44661 (6)0.0648 (4)0.58754 (13)0.0161 (2)
C60.41693 (6)0.2018 (3)0.68361 (12)0.0129 (2)
C70.33505 (5)0.3278 (3)0.77494 (12)0.0113 (2)
C80.27433 (5)0.3583 (3)0.80211 (12)0.0117 (2)
C90.22743 (6)0.2529 (4)0.73926 (13)0.0141 (2)
C100.17415 (6)0.3143 (4)0.78798 (14)0.0162 (3)
C110.16835 (6)0.4757 (4)0.89631 (14)0.0166 (3)
C120.21568 (6)0.5858 (4)0.95898 (14)0.0145 (2)
C130.26863 (5)0.5257 (3)0.91037 (13)0.0120 (2)
C140.32527 (5)0.6219 (3)0.95612 (12)0.0122 (2)
C150.36646 (6)0.4822 (3)0.86782 (12)0.0116 (2)
H2A0.5309 (9)0.475 (6)0.834 (3)0.024 (6)*
H3A0.5758 (10)0.236 (6)0.671 (2)0.022 (5)*
H4A0.5277 (11)0.002 (7)0.519 (3)0.033 (7)*
H5A0.4213 (10)0.031 (6)0.527 (3)0.025 (6)*
H9A0.2305 (9)0.133 (6)0.665 (2)0.024 (6)*
H10A0.1405 (11)0.235 (6)0.746 (2)0.024 (6)*
H11A0.1301 (12)0.493 (7)0.927 (2)0.035 (7)*
H12A0.2086 (14)0.697 (8)1.033 (3)0.048 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0188 (4)0.0209 (5)0.0120 (5)0.0003 (4)0.0011 (4)0.0053 (4)
N10.0141 (5)0.0137 (5)0.0121 (5)0.0003 (4)0.0006 (4)0.0002 (4)
N20.0165 (5)0.0125 (5)0.0108 (5)0.0005 (4)0.0005 (4)0.0006 (4)
C10.0136 (5)0.0118 (5)0.0119 (5)0.0001 (4)0.0002 (4)0.0004 (4)
C20.0154 (5)0.0150 (5)0.0173 (6)0.0003 (5)0.0013 (5)0.0007 (5)
C30.0160 (5)0.0164 (6)0.0217 (7)0.0021 (5)0.0039 (5)0.0026 (5)
C40.0197 (6)0.0157 (6)0.0181 (6)0.0021 (5)0.0063 (5)0.0014 (5)
C50.0195 (6)0.0137 (6)0.0150 (6)0.0015 (5)0.0026 (5)0.0010 (4)
C60.0156 (5)0.0117 (5)0.0113 (6)0.0004 (4)0.0006 (5)0.0002 (4)
C70.0132 (5)0.0103 (5)0.0103 (5)0.0007 (4)0.0007 (4)0.0002 (4)
C80.0133 (5)0.0114 (5)0.0106 (5)0.0006 (4)0.0011 (4)0.0001 (4)
C90.0149 (5)0.0135 (5)0.0139 (6)0.0006 (4)0.0027 (4)0.0007 (4)
C100.0138 (5)0.0144 (6)0.0204 (7)0.0012 (4)0.0025 (5)0.0012 (5)
C110.0146 (5)0.0161 (6)0.0193 (7)0.0004 (4)0.0012 (5)0.0012 (5)
C120.0159 (5)0.0142 (5)0.0135 (6)0.0005 (4)0.0021 (5)0.0000 (5)
C130.0132 (5)0.0115 (5)0.0111 (5)0.0001 (4)0.0004 (4)0.0002 (4)
C140.0128 (5)0.0128 (5)0.0112 (5)0.0003 (4)0.0006 (4)0.0002 (4)
C150.0135 (5)0.0121 (5)0.0092 (5)0.0001 (4)0.0007 (4)0.0005 (4)
Geometric parameters (Å, º) top
O1—C141.2193 (18)C7—C151.4321 (19)
N1—C151.3070 (17)C7—C81.4768 (17)
N1—C11.3793 (18)C8—C91.3865 (18)
N2—C71.3142 (17)C8—C131.4106 (19)
N2—C61.3800 (17)C9—C101.402 (2)
C1—C21.4197 (17)C9—H9A0.97 (3)
C1—C61.4292 (18)C10—C111.401 (2)
C2—C31.377 (2)C10—H10A0.98 (3)
C2—H2A0.99 (3)C11—C121.399 (2)
C3—C41.413 (2)C11—H11A0.98 (3)
C3—H3A0.96 (2)C12—C131.3935 (18)
C4—C51.381 (2)C12—H12A0.97 (3)
C4—H4A0.98 (3)C13—C141.4876 (18)
C5—C61.4140 (19)C14—C151.509 (2)
C5—H5A1.00 (3)
C15—N1—C1113.99 (12)C9—C8—C7130.26 (13)
C7—N2—C6114.00 (12)C13—C8—C7108.50 (11)
N1—C1—C2118.59 (13)C8—C9—C10117.57 (14)
N1—C1—C6121.85 (12)C8—C9—H9A122.5 (13)
C2—C1—C6119.55 (13)C10—C9—H9A119.9 (13)
C3—C2—C1119.96 (14)C11—C10—C9121.35 (13)
C3—C2—H2A118.1 (14)C11—C10—H10A119.6 (15)
C1—C2—H2A121.9 (14)C9—C10—H10A119.0 (15)
C2—C3—C4120.54 (13)C12—C11—C10121.02 (13)
C2—C3—H3A121.2 (16)C12—C11—H11A122.4 (16)
C4—C3—H3A118.3 (16)C10—C11—H11A116.5 (16)
C5—C4—C3120.66 (13)C13—C12—C11117.61 (14)
C5—C4—H4A124.1 (17)C13—C12—H12A126 (2)
C3—C4—H4A115.2 (17)C11—C12—H12A117 (2)
C4—C5—C6120.21 (14)C12—C13—C8121.20 (13)
C4—C5—H5A126.7 (15)C12—C13—C14128.92 (14)
C6—C5—H5A113.1 (15)C8—C13—C14109.87 (11)
N2—C6—C5118.62 (13)O1—C14—C13128.22 (13)
N2—C6—C1122.31 (12)O1—C14—C15126.88 (12)
C5—C6—C1119.07 (12)C13—C14—C15104.86 (11)
N2—C7—C15123.41 (13)N1—C15—C7124.43 (13)
N2—C7—C8128.27 (12)N1—C15—C14127.18 (12)
C15—C7—C8108.32 (12)C7—C15—C14108.39 (12)
C9—C8—C13121.23 (12)
C15—N1—C1—C2179.01 (12)C8—C9—C10—C110.1 (2)
C15—N1—C1—C60.06 (18)C9—C10—C11—C120.9 (2)
N1—C1—C2—C3178.21 (13)C10—C11—C12—C130.7 (2)
C6—C1—C2—C30.8 (2)C11—C12—C13—C80.3 (2)
C1—C2—C3—C40.8 (2)C11—C12—C13—C14178.39 (13)
C2—C3—C4—C50.3 (2)C9—C8—C13—C121.12 (19)
C3—C4—C5—C60.2 (2)C7—C8—C13—C12179.14 (12)
C7—N2—C6—C5178.35 (12)C9—C8—C13—C14177.81 (12)
C7—N2—C6—C11.21 (18)C7—C8—C13—C141.93 (14)
C4—C5—C6—N2179.42 (13)C12—C13—C14—O13.7 (2)
C4—C5—C6—C10.1 (2)C8—C13—C14—O1175.12 (13)
N1—C1—C6—N20.9 (2)C12—C13—C14—C15178.69 (14)
C2—C1—C6—N2179.87 (13)C8—C13—C14—C152.50 (14)
N1—C1—C6—C5178.63 (12)C1—N1—C15—C70.42 (19)
C2—C1—C6—C50.32 (19)C1—N1—C15—C14178.69 (12)
C6—N2—C7—C150.74 (18)N2—C7—C15—N10.1 (2)
C6—N2—C7—C8179.53 (12)C8—C7—C15—N1179.70 (12)
N2—C7—C8—C91.1 (2)N2—C7—C15—C14179.18 (12)
C15—C7—C8—C9179.17 (14)C8—C7—C15—C141.05 (14)
N2—C7—C8—C13179.22 (13)O1—C14—C15—N13.7 (2)
C15—C7—C8—C130.53 (14)C13—C14—C15—N1178.64 (12)
C13—C8—C9—C100.89 (19)O1—C14—C15—C7175.53 (13)
C7—C8—C9—C10179.44 (13)C13—C14—C15—C72.13 (14)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···O1i0.96 (2)2.55 (2)3.401 (2)148.3 (19)
C9—H9A···O1ii0.97 (3)2.49 (3)3.2458 (18)134.0 (18)
Symmetry codes: (i) x+1, y+1, z1/2; (ii) x+1/2, y1, z1/2.

Experimental details

Crystal data
Chemical formulaC15H8N2O
Mr232.23
Crystal system, space groupOrthorhombic, Pca21
Temperature (K)100
a, b, c (Å)23.688 (3), 3.7862 (5), 11.5730 (16)
V3)1038.0 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.65 × 0.17 × 0.09
Data collection
DiffractometerBruker APEXII DUO CCD
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.940, 0.991
No. of measured, independent and
observed [I > 2σ(I)] reflections
8012, 2004, 1879
Rint0.031
(sin θ/λ)max1)0.763
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.096, 1.05
No. of reflections2004
No. of parameters195
No. of restraints1
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.35, 0.23

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···O1i0.96 (2)2.55 (2)3.401 (2)148.3 (19)
C9—H9A···O1ii0.97 (3)2.49 (3)3.2458 (18)134.0 (18)
Symmetry codes: (i) x+1, y+1, z1/2; (ii) x+1/2, y1, z1/2.
 

Footnotes

Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

RMG, RH and OS thank Universiti Sains Malaysia (USM) for the University Grant 1001/PTEKIND/8140152. MH and HKF thank the Malaysian Government and USM for the Research University Golden Goose grant No. 1001/PFIZIK/811012. RMG and MH also thank USM for post-doctoral research fellowships.

References

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