supplementary materials


ff2123 scheme

Acta Cryst. (2014). E70, o28    [ doi:10.1107/S1600536813032704 ]

1-Nitro-9H-carbazole

P. Kautny and B. Stöger

Abstract top

In the title mol­ecule, C12H8N2O2, the nitro group is tilted slightly with respect to the carbazole moiety [angle between the least-squares planes = 4.43 (9)°]. In the crystal, the mol­ecules are connected via pairs of N-H...O hydrogen bonds into dimers with -1 symmetry. The dimers in turn are arranged into layers parallel to (10-1).

Comment top

In the last years, arylamines have been widely employed as electron donors in materials for organo-electronic applications as for example organic light emitting diodes (OLEDs) (Shirota and Kageyama, 2007; Tao et al., 2011; Yook and Lee, 2012). In the course of systematic investigations of the impact of planarized arylamine moieties on the photo-physical and electro-chemical properties of bipolar host materials for phosphorescent OLEDs (Kautny, et al., 2013), we synthesized the title compound 1-nitro-9H-carbazole (I) starting from 2-bromo-N-(2-nitrophenyl)benzenamine. Single crystals of (I) grown from CDCl3 were subjected to X-ray diffraction for structure elucidation. To our knowledge, (I) is the first structurally characterized nitrocarbazole.

(I) crystallizes in the space group P21/n with one molecule in the asymmetric unit. As expected, due to the conjugated π-electron system, the molecule is virtually flat. The largest distance from the least-squares (LS) plane defined by the atoms of the carbazole ring (N1, C1–C12) is only 0.1420 (10) Å, as observed for the O1 atom of the nitro group. The N2 atom of the nitro group is located at 0.0512 (10) Å from the plane, all other atoms are closer than 0.04 Å. The plane defined by the three atoms of the nitro group (N2, O1, O2) is inclined to the LS plane of the carbazole ring by 4.43 (9)°.

The molecules are connected via medium-strength N—H···O hydrogen bonds (N···O: 2.9940 (10) Å) to dimers with 1 symmetry (Fig. 1). The packing of the dimers, on the other hand, is solely controlled by van-der-Waals interactions. The dimers are arranged into distinct crystallo-chemical layers parallel to (101), whereby adjacent dimers are related by the n-glide (Fig. 2).

Related literature top

For application of arylamines as electron donors, see: Shirota & Kageyama (2007); Tao et al. (2011); Yook & Lee (2012); Kautny et al. (2013). For synthesis of the catalyst (NHC)Pd(allyl)Cl, see: Marion et al. (2006).

Experimental top

2-Bromo-N-(2-nitrophenyl)benzenamine (147 mg, 0.50 mmol, 1 eq.), K2CO3 (138 mg, 1 mmol, 2 eq.) and (NHC)Pd(allyl)Cl (Marion et al., 2006) (6 mg, 10 µmol, 2 mol%) in DMAc (2.5 ml) were heated at 140 °C for 150 h in a capped vial using a heating block. After cooling the reaction mixture was poured on water and extracted with Et2O. The combined organic layers were dried over anhydrous Na2SO4 and concentrated under reduced pressure. Column chromatography (light petroleum:CH2Cl2 75:25 60:40) yielded 1-nitro-9H-carbazole (18 mg, 0.08 mmol, 17%) as a yellow solid. 1H NMR (200 MHz, CDCl3): δ = 10.01 (bs, 1H), 8.37–8.31 (m, 2H), 8.10 (d, J=7.8 Hz, 1H), 7.60–7.50 (m, 2H), 7.39–7.26 (m, 2H) p.p.m.. 13C NMR (50 MHz, CDCl3): δ = 139.7 (s), 133.7 (s), 132.1 (s), 127.7 (d), 127.5 (d), 127.4 (s), 122.2 (s), 121.9 (d), 121.2 (d), 120.6 (d), 118.7 (d), 111.6 (d) p.p.m.. Crystals suitable for single-crystal diffraction were grown by slow evaporation of a CDCl3 solution.

Refinement top

The structure was refined against F values using the Jana2006 software package (Petříček et al., 2006). The non-H atoms were located in the electron density map obtained by charge-flipping and refined with anisotropic displacement parameters. The H atoms were located in difference Fourier maps and freely refined.

Computing details top

Data collection: APEX2 (Bruker, 2013); cell refinement: SAINT-Plus (Bruker, 2013); data reduction: SAINT-Plus (Bruker, 2013); program(s) used to solve structure: SUPERFLIP (Palatinus & Chapuis, 2007); program(s) used to refine structure: JANA2006 (Petříček et al., 2006); molecular graphics: ATOMS (Dowty, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures top
[Figure 1] Fig. 1. Dimer of (I) molecules related by inversion and connected via N—O···H hydrogen bonds. C, N and O atoms are represented by grey, blue and red ellipsoids drawn at the 75% probability level, H atoms by white spheres of arbitrary radius. Hydrogen bonds are indicated by dashed lines.
[Figure 2] Fig. 2. The crystal structure of (I) viewed down [010]. Atoms are represented by spheres of arbitrary radius. Colour codes as in Fig. 1.
1-Nitro-9H-carbazole top
Crystal data top
C12H8N2O2F(000) = 440
Mr = 212.2Dx = 1.493 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 17802 reflections
a = 10.4400 (3) Åθ = 2.4–30.1°
b = 5.3148 (2) ŵ = 0.11 mm1
c = 17.2638 (6) ÅT = 100 K
β = 99.7460 (16)°Plate, dark yellow
V = 944.08 (6) Å30.76 × 0.42 × 0.20 mm
Z = 4
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2794 independent reflections
Radiation source: X-ray tube2397 reflections with I > 3σ(I)
Graphite monochromatorRint = 0.021
ω and φ scansθmax = 30.2°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
h = 1414
Tmin = 0.95, Tmax = 0.98k = 77
30130 measured reflectionsl = 2424
Refinement top
Refinement on F0 constraints
R[F2 > 2σ(F2)] = 0.040All H-atom parameters refined
wR(F2) = 0.068Weighting scheme based on measured s.u.'s w = 1/(σ2(F) + 0.0009F2)
S = 1.89(Δ/σ)max = 0.015
2794 reflectionsΔρmax = 0.32 e Å3
177 parametersΔρmin = 0.21 e Å3
0 restraints
Crystal data top
C12H8N2O2V = 944.08 (6) Å3
Mr = 212.2Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.4400 (3) ŵ = 0.11 mm1
b = 5.3148 (2) ÅT = 100 K
c = 17.2638 (6) Å0.76 × 0.42 × 0.20 mm
β = 99.7460 (16)°
Data collection top
Bruker Kappa APEXII CCD
diffractometer
2794 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2013)
2397 reflections with I > 3σ(I)
Tmin = 0.95, Tmax = 0.98Rint = 0.021
30130 measured reflectionsθmax = 30.2°
Refinement top
R[F2 > 2σ(F2)] = 0.040All H-atom parameters refined
wR(F2) = 0.068Δρmax = 0.32 e Å3
S = 1.89Δρmin = 0.21 e Å3
2794 reflectionsAbsolute structure: ?
177 parametersAbsolute structure parameter: ?
0 restraintsRogers parameter: ?
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
O10.89295 (6)0.40415 (13)0.03186 (4)0.0210 (2)
O20.72187 (8)0.32391 (14)0.08415 (4)0.0262 (2)
N10.94574 (7)0.15206 (14)0.09492 (4)0.0148 (2)
N20.79470 (7)0.27907 (15)0.03678 (4)0.0172 (2)
C10.84182 (8)0.02688 (16)0.07504 (5)0.0136 (2)
C20.76585 (8)0.07065 (16)0.01702 (5)0.0155 (2)
C30.66091 (8)0.08542 (18)0.01060 (5)0.0190 (3)
C40.62951 (9)0.28368 (19)0.06284 (6)0.0210 (3)
C50.70463 (9)0.33376 (17)0.12071 (6)0.0184 (3)
C60.81094 (8)0.18269 (16)0.12662 (5)0.0145 (2)
C70.90505 (8)0.17966 (16)0.17915 (5)0.0148 (2)
C80.92934 (10)0.33696 (17)0.24006 (5)0.0193 (3)
C91.03157 (10)0.27687 (19)0.27885 (6)0.0226 (3)
C101.10889 (9)0.06296 (19)0.25785 (6)0.0222 (3)
C111.08747 (9)0.09238 (17)0.19688 (6)0.0187 (3)
C120.98542 (8)0.03034 (16)0.15802 (5)0.0145 (2)
H111.1422 (11)0.232 (3)0.1779 (8)0.028 (3)*
H50.6817 (11)0.477 (2)0.1571 (7)0.019 (3)*
H40.5546 (13)0.390 (2)0.0614 (8)0.027 (3)*
H80.8730 (12)0.480 (2)0.2542 (8)0.020 (3)*
H91.0526 (14)0.384 (3)0.3211 (10)0.039 (4)*
H30.6077 (12)0.069 (2)0.0296 (8)0.026 (3)*
H101.1776 (11)0.026 (2)0.2858 (7)0.018 (3)*
Hn10.9851 (12)0.275 (3)0.0690 (9)0.029 (3)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0207 (3)0.0221 (4)0.0196 (3)0.0021 (3)0.0017 (3)0.0039 (3)
O20.0301 (4)0.0324 (4)0.0187 (4)0.0068 (3)0.0117 (3)0.0020 (3)
N10.0153 (3)0.0140 (4)0.0157 (4)0.0019 (3)0.0041 (3)0.0018 (3)
N20.0185 (4)0.0198 (4)0.0132 (4)0.0041 (3)0.0026 (3)0.0014 (3)
C10.0124 (4)0.0148 (4)0.0133 (4)0.0004 (3)0.0010 (3)0.0016 (3)
C20.0141 (4)0.0184 (4)0.0137 (4)0.0018 (3)0.0017 (3)0.0012 (3)
C30.0138 (4)0.0248 (5)0.0187 (4)0.0012 (3)0.0033 (3)0.0059 (3)
C40.0158 (4)0.0226 (5)0.0242 (5)0.0035 (3)0.0018 (3)0.0064 (4)
C50.0177 (4)0.0170 (4)0.0187 (4)0.0024 (3)0.0017 (3)0.0033 (3)
C60.0149 (4)0.0141 (4)0.0135 (4)0.0003 (3)0.0005 (3)0.0014 (3)
C70.0163 (4)0.0146 (4)0.0127 (4)0.0016 (3)0.0007 (3)0.0013 (3)
C80.0246 (5)0.0171 (4)0.0151 (4)0.0053 (3)0.0001 (3)0.0013 (3)
C90.0279 (5)0.0244 (5)0.0160 (4)0.0102 (4)0.0053 (3)0.0004 (3)
C100.0237 (4)0.0246 (5)0.0201 (4)0.0095 (4)0.0089 (3)0.0064 (3)
C110.0177 (4)0.0182 (4)0.0215 (4)0.0026 (3)0.0067 (3)0.0045 (3)
C120.0152 (4)0.0140 (4)0.0144 (4)0.0024 (3)0.0030 (3)0.0018 (3)
Geometric parameters (Å, º) top
O1—N21.2372 (11)C5—C61.3875 (13)
O2—N21.2305 (12)C5—H50.991 (11)
N1—C11.3651 (12)C6—C71.4456 (13)
N1—C121.3890 (12)C7—C81.3997 (13)
N1—Hn10.857 (13)C7—C121.4068 (12)
N2—C21.4442 (11)C8—C91.3898 (15)
C1—C21.3984 (13)C8—H80.969 (13)
C1—C61.4283 (12)C9—C101.4058 (14)
C2—C31.3935 (13)C9—H90.981 (16)
C3—C41.3897 (14)C10—C111.3854 (14)
C3—H30.964 (15)C10—H100.951 (13)
C4—C51.3962 (15)C11—C121.3914 (14)
C4—H40.967 (13)C11—H110.960 (13)
C1—N1—C12108.99 (7)C1—C6—C5120.29 (8)
C1—N1—Hn1124.9 (10)C1—C6—C7106.06 (7)
C12—N1—Hn1125.8 (10)C5—C6—C7133.60 (8)
O1—N2—O2123.66 (8)C6—C7—C8133.90 (8)
O1—N2—C2116.94 (8)C6—C7—C12106.56 (7)
O2—N2—C2119.40 (8)C8—C7—C12119.52 (8)
N1—C1—C2132.09 (8)C7—C8—C9118.44 (8)
N1—C1—C6109.18 (8)C7—C8—H8118.6 (8)
C2—C1—C6118.73 (8)C9—C8—H8122.9 (8)
N2—C2—C1120.43 (8)C8—C9—C10121.06 (9)
N2—C2—C3119.11 (8)C8—C9—H9120.8 (9)
C1—C2—C3120.46 (8)C10—C9—H9118.1 (9)
C2—C3—C4120.13 (9)C9—C10—C11121.22 (10)
C2—C3—H3124.0 (7)C9—C10—H10119.1 (7)
C4—C3—H3115.9 (7)C11—C10—H10119.7 (7)
C3—C4—C5120.64 (9)C10—C11—C12117.41 (8)
C3—C4—H4121.8 (9)C10—C11—H11123.9 (8)
C5—C4—H4117.5 (9)C12—C11—H11118.6 (8)
C4—C5—C6119.70 (8)N1—C12—C7109.20 (8)
C4—C5—H5119.7 (7)N1—C12—C11128.47 (8)
C6—C5—H5120.6 (7)C7—C12—C11122.32 (8)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—Hn1···O1i0.857 (13)2.159 (13)2.9940 (10)164.6 (14)
Symmetry code: (i) x+2, y+1, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—Hn1···O1i0.857 (13)2.159 (13)2.9940 (10)164.6 (14)
Symmetry code: (i) x+2, y+1, z.
Acknowledgements top

The X-ray centre (XRC) of the Vienna University of Technology is acknowledged for providing access to the single-crystal diffractometer and for financial support.

references
References top

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