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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 70| Part 12| December 2014| Pages o1283-o1284
doi:10.1107/S1600536814025367

Crystal structure of 9-butyl-3-(9-butyl-9H-carbazol-3-yl)-9H-carbazole

K. Stalindurai,a C. Ramalingan,a B. Sridharb and S. Selvanayagamc*

aDepartment of Chemistry, Kalasalingam University, Krishnankoil 626 126, India, bLaboratory of X-ray Crystallography, Indian Institute of Chemical Technology, Hyderabad 500 067, India, and cDepartment of Physics & International Research Centre, Kalasalingam University, Krishnankoil 626 126, India
*Correspondence e-mail: s_selvanayagam@rediffmail.com

Edited by O. Blacque, University of Zürich, Switzerland (Received 15 November 2014; accepted 19 November 2014; online 21 November 2014)

In the title carbazole derivative, C32H32N2, the mol­ecule resides on a crystallographic twofold axis, which runs through the central C—C bond. The carbazole ring system is almost planar, with a maximum deviation of 0.041 (1) Å for one of the ring-junction C atoms. The crystal packing is stabilized by C—H⋯π inter­actions only, which form a C(7) chain-like arrangement along [110] in the unit cell.

CCDC reference: 1034987

1. Related literature

For general background to carbazole derivatives and their applications, see: Giraud et al. (2014[Giraud, F., Bourhis, M., Nauton, L., Thery, V., Herfindal, L., Doskeland, S. O., Anizon, F. & Moreau, P. (2014). Bioorg. Chem. 57, 108-115.]); Bandgar et al. (2012[Bandgar, B. P., Adsul, L. K., Chavan, H. V., Jalde, S. S., Shringare, S. N., Shaikh, R., Meshram, R. J., Gacche, R. N. & Masand, V. (2012). Bioorg. Med. Chem. Lett. 22, 5839-5844.]); Gu et al. (2014[Gu, W., Qiao, C., Wang, S.-F., Hao, Y. & Miao, T.-T. (2014). Bioorg. Med. Chem. Lett. 24, 328-331.]); Wang et al. (2011[Wang, Y.-Q., Li, X.-H., He, Q., Chen, Y., Xie, Y.-Y., Ding, J., Miao, Z.-H. & Yang, C.-H. (2011). Eur. J. Med. Chem. 46, 5878-5884.]); Thiratmatrakul et al. (2014[Thiratmatrakul, S., Yenjai, C., Waiwut, P., Vajragupta, O., Reubroycharoen, P., Tohda, M. & Boonyarat, C. (2014). Eur. J. Med. Chem. 75, 21-30.]); Shi et al. (2012[Shi, L., Liu, Z., Dong, G., Duan, L., Qiu, Y., Jia, J., Guo, W., Zhao, D., Cui, D. & Tao, X. (2012). Chem. Eur. J. 18, 8092-8099.]); Tavasli et al. (2012[Tavasli, M., Moore, T. N., Zheng, Y., Bryce, M. R., Fox, M. A., Griffiths, G. C., Jankus, V., Al-Attar, H. A. & Monkman, A. P. (2012). J. Mater. Chem. 22, 6419-6428.]); Kim et al. (2011[Kim, S.-J., Zhang, Y., Zuniga, C., Barlow, S., Marder, S. R. & Kippelen, B. (2011). Org. Electron. 12, 492-496.]); Zhuang et al. (2012[Zhuang, J., Su, W., Li, W., Zhou, Y., Shen, Q. & Zhou, M. (2012). Org. Electron. 13, 2210-2219.]). For the preparation of the title compound, see: Ramalingan et al. (2010[Ramalingan, C., Park, S.-J., Lee, I.-S. & Kwak, Y.-W. (2010). Tetrahedron, 66, 2987-2994.]).

[Scheme 1]

2. Experimental

2.1. Crystal data

  • C32H32N2

  • Mr = 444.59

  • Monoclinic, P 21 /n

  • a = 5.6184 (4) Å

  • b = 11.0946 (7) Å

  • c = 19.4673 (13) Å

  • β = 95.982 (1)°

  • V = 1206.86 (14) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 292 K

  • 0.21 × 0.19 × 0.17 mm

2.2. Data collection

  • Bruker SMART APEX CCD area-detector diffractometer

  • 13872 measured reflections

  • 2928 independent reflections

  • 2319 reflections with I > 2σ(I)

  • Rint = 0.026

2.3. Refinement

  • R[F2 > 2σ(F2)] = 0.061

  • wR(F2) = 0.159

  • S = 1.12

  • 2928 reflections

  • 155 parameters

  • H-atom parameters constrained

  • Δρmax = 0.24 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C7–C12 ring.
D—H⋯A D—H H⋯A D⋯A D—H⋯A
C15—H15B⋯Cgi 0.97 2.98 3.838 (2) 148
Symmetry code: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART 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: SHELXL2013 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL2013 and PLATON.

Supporting information

CCDC reference: 1034987

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536814025367/zq2229sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536814025367/zq2229Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536814025367/zq2229Isup3.cml

checkCIF report


Comment top

Carbazole based materials play vital roles in various areas of research. Various carbazole based heterocycles exhibit a diverse range of biological activities including pim kinase inhibitory (Giraud et al., 2014), anti-inflammatory, antioxidant (Bandgar et al., 2012), antimicrobial (Gu et al., 2014), antitumor (Wang et al., 2011), and anti-Alzheimer (Thiratmatrakul et al., 2014) activities etc. On the other hand, this class of materials has been identified as potential ones for OLED applications (Shi et al., 2012.; Tavasli et al., 2012; Kim et al., 2011; Zhuang et al., 2012). As an intermediate for the development of new carbazole based materials for biological/OLED applications, a dibutylbicarbazole has been synthesized and single crystals were grown by slow evaporation in ethanol.

The X-ray study confirmed the molecular structure and atomic connectivity of the title compound, as illustrated in Fig. 1. The bond distance C4—C4i of 1.488 (3) Å [symmetry code: (i) -x,-y+2,-z] confirms the single bond character. The sum of the angles at N1 (358.9°) is in accordance with sp2 hybridization.

The carbazole ring system is planar with a maximum deviation of -0.041 (1) Å for atom C7. The atom C13 attached to the carbazole ring system deviates by 0.250 (1) Å from the best plane of the carbazole ring system.

In addition to the van der Waals interactions, the molecular packing is influenced by intermolecular C—H···π interactions, such that atom H15B is 2.98 Å from the centroid of the phenyl ring (C7-C12) at (1/2-x, -1/2+y, 1/2-z) with a C15—H15B···.centroid angle of 148° and a C15···centroid distance of 3.838 (2) Å. This interactions form a C(7) chain like arrangement in the unit cell (Fig. 2).

Related literature top

For general background to carbazole derivatives and their applications, see: Giraud et al. (2014); Bandgar et al. (2012); Gu et al. (2014); Wang et al. (2011); Thiratmatrakul et al. (2014); Shi et al. (2012); Tavasli et al. (2012); Kim et al. (2011); Zhuang et al. (2012). For the preparation of the title compound, see: Ramalingan et al. (2010).

Experimental top

In a round-bottomed flask (250 ml), iron(III) chloride (44.80 mmol) in chloroform (100 ml) was taken under nitrogen atmosphere. Then, 9-butyl-9H-carbazole (11.20 mmol) (Ramalingan et al., 2010) in chloroform (50 ml) was added in a drop-wise fashion and was stirred at ambient temperature for 1 hour. After the addition of a sodium hydroxide solution (10%), the organic phase was separated and the aqueous phase was extracted with chloroform. The combined organic phases were dried and concentrated to obtain the crude product which was dissolved in chloroform (15 ml) and reprecipitated slowly using methanol (200 ml). The product, thus, obtained was filtered, dried under vacuum at ambient temperature. Single crystals of (I) were obtained by slow evaporation of ethanol solution of the title compound at room temperature.

Refinement top

H atoms were placed in idealized positions and allowed to ride on their parent atoms, with C—H distances of 0.93-0.97 Å, and Uiso(H) = 1.5Ueq(methyl C) and Uiso(H) = 1.2Ueq for other C atoms.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL2013 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
Fig. 1. The molecular structure of the title compound, showing the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

Fig. 2. Molecular packing of the title compound, viewed along the a axis; C—H···π interactions are shown as dashed lines.For the sake of clarity, H atoms, not involved in hydrogen bonds, have been omitted for clarity.
9-Butyl-3-(9-butyl-9H-carbazol-3-yl)-9H-carbazole top
Crystal data top
C32H32N2F(000) = 476
Mr = 444.59Dx = 1.223 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
a = 5.6184 (4) ÅCell parameters from 9858 reflections
b = 11.0946 (7) Åθ = 2.4–27.2°
c = 19.4673 (13) ŵ = 0.07 mm−1
β = 95.982 (1)°T = 292 K
V = 1206.86 (14) Å3Block, colourless
Z = 20.21 × 0.19 × 0.17 mm
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		Rint = 0.026
Radiation source: fine-focus sealed tubeθmax = 28.3°, θmin = 2.1°
ω scansh = −7→7
13872 measured reflectionsk = −14→14
2928 independent reflectionsl = −25→25
2319 reflections with I > 2σ(I)
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.061H-atom parameters constrained
wR(F2) = 0.159 w = 1/[σ2(Fo2) + (0.0782P)2 + 0.1445P]
where P = (Fo2 + 2Fc2)/3
S = 1.12(Δ/σ)max < 0.001
2928 reflectionsΔρmax = 0.24 e Å−3
155 parametersΔρmin = −0.19 e Å−3
Crystal data top
C32H32N2V = 1206.86 (14) Å3
Mr = 444.59Z = 2
Monoclinic, P21/nMo Kα radiation
a = 5.6184 (4) ŵ = 0.07 mm−1
b = 11.0946 (7) ÅT = 292 K
c = 19.4673 (13) Å0.21 × 0.19 × 0.17 mm
β = 95.982 (1)°
Data collection top
Bruker SMART APEX CCD area-detector
diffractometer		2319 reflections with I > 2σ(I)
13872 measured reflectionsRint = 0.026
2928 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0610 restraints
wR(F2) = 0.159H-atom parameters constrained
S = 1.12Δρmax = 0.24 e Å−3
2928 reflectionsΔρmin = −0.19 e Å−3
155 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N10.3407 (2)0.68730 (12)0.15991 (7)0.0515 (4)
C10.2740 (3)0.77442 (13)0.11101 (8)0.0453 (4)
C20.3743 (3)0.80464 (14)0.05125 (9)0.0520 (4)
H20.51120.76590.03950.062*
C30.2664 (3)0.89298 (14)0.00987 (8)0.0498 (4)
H30.33430.9134−0.03010.060*
C40.0581 (3)0.95478 (12)0.02450 (7)0.0432 (3)
C5−0.0317 (3)0.92638 (13)0.08650 (8)0.0464 (4)
H5−0.16440.96770.09910.056*
C60.0733 (3)0.83737 (14)0.12995 (7)0.0445 (4)
C70.0185 (3)0.78577 (14)0.19467 (8)0.0487 (4)
C8−0.1572 (3)0.80724 (17)0.23854 (9)0.0601 (5)
H8−0.26880.86850.22890.072*
C9−0.1633 (4)0.7361 (2)0.29660 (9)0.0711 (5)
H9−0.28010.74960.32630.085*
C100.0034 (4)0.64469 (19)0.31106 (10)0.0718 (6)
H10−0.00450.59800.35040.086*
C110.1792 (4)0.62115 (17)0.26904 (9)0.0627 (5)
H110.29000.55980.27930.075*
C120.1855 (3)0.69250 (14)0.21042 (8)0.0502 (4)
C130.5130 (3)0.59184 (15)0.15104 (9)0.0572 (4)
H13A0.55330.55180.19500.069*
H13B0.65840.62750.13720.069*
C140.4206 (3)0.49911 (16)0.09770 (9)0.0580 (4)
H14A0.39290.53860.05310.070*
H14B0.54390.43880.09440.070*
C150.1935 (3)0.43619 (18)0.11230 (10)0.0661 (5)
H15A0.06790.49570.11430.079*
H15B0.21910.39730.15710.079*
C160.1125 (4)0.3428 (2)0.05817 (12)0.0911 (7)
H16A0.09760.37970.01330.137*
H16B−0.03960.31070.06740.137*
H16C0.22810.27890.05950.137*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0529 (7)0.0499 (8)0.0513 (8)0.0010 (6)0.0039 (6)0.0007 (6)
C10.0430 (7)0.0437 (8)0.0487 (8)−0.0055 (6)0.0015 (6)−0.0043 (6)
C20.0426 (8)0.0532 (9)0.0618 (10)0.0013 (7)0.0127 (7)0.0005 (7)
C30.0476 (8)0.0525 (9)0.0511 (9)−0.0050 (7)0.0130 (7)0.0015 (7)
C40.0439 (7)0.0388 (7)0.0468 (8)−0.0065 (6)0.0050 (6)−0.0071 (6)
C50.0473 (8)0.0457 (8)0.0467 (8)0.0007 (6)0.0077 (6)−0.0086 (6)
C60.0469 (8)0.0437 (8)0.0428 (8)−0.0066 (6)0.0049 (6)−0.0089 (6)
C70.0543 (9)0.0495 (8)0.0420 (8)−0.0086 (7)0.0035 (6)−0.0092 (7)
C80.0673 (11)0.0648 (11)0.0494 (9)−0.0063 (8)0.0124 (8)−0.0130 (8)
C90.0836 (13)0.0846 (14)0.0484 (10)−0.0165 (11)0.0218 (9)−0.0116 (9)
C100.0935 (14)0.0744 (13)0.0483 (10)−0.0190 (11)0.0109 (10)0.0034 (9)
C110.0759 (12)0.0602 (10)0.0511 (10)−0.0085 (9)0.0019 (8)0.0033 (8)
C120.0558 (9)0.0498 (9)0.0441 (8)−0.0093 (7)0.0015 (7)−0.0056 (6)
C130.0491 (9)0.0559 (10)0.0651 (10)0.0031 (7)−0.0010 (7)0.0033 (8)
C140.0574 (10)0.0579 (10)0.0594 (10)0.0074 (8)0.0090 (8)0.0012 (8)
C150.0651 (11)0.0693 (11)0.0643 (11)−0.0039 (9)0.0089 (9)−0.0126 (9)
C160.0988 (17)0.0948 (16)0.0795 (14)−0.0229 (13)0.0083 (12)−0.0273 (13)
Geometric parameters (Å, º) top
N1—C11.381 (2)C9—C101.389 (3)
N1—C121.382 (2)C9—H90.9300
N1—C131.457 (2)C10—C111.372 (3)
C1—C21.385 (2)C10—H100.9300
C1—C61.408 (2)C11—C121.392 (2)
C2—C31.369 (2)C11—H110.9300
C2—H20.9300C13—C141.515 (2)
C3—C41.411 (2)C13—H13A0.9700
C3—H30.9300C13—H13B0.9700
C4—C51.392 (2)C14—C151.507 (3)
C4—C4i1.488 (3)C14—H14A0.9700
C5—C61.391 (2)C14—H14B0.9700
C5—H50.9300C15—C161.514 (3)
C6—C71.446 (2)C15—H15A0.9700
C7—C81.392 (2)C15—H15B0.9700
C7—C121.409 (2)C16—H16A0.9600
C8—C91.382 (3)C16—H16B0.9600
C8—H80.9300C16—H16C0.9600
C1—N1—C12108.37 (13)C9—C10—H10119.0
C1—N1—C13124.27 (14)C10—C11—C12117.53 (19)
C12—N1—C13126.23 (14)C10—C11—H11121.2
N1—C1—C2130.04 (14)C12—C11—H11121.2
N1—C1—C6109.51 (13)N1—C12—C11129.16 (16)
C2—C1—C6120.44 (14)N1—C12—C7109.34 (14)
C3—C2—C1118.26 (14)C11—C12—C7121.50 (16)
C3—C2—H2120.9N1—C13—C14112.98 (14)
C1—C2—H2120.9N1—C13—H13A109.0
C2—C3—C4123.69 (15)C14—C13—H13A109.0
C2—C3—H3118.2N1—C13—H13B109.0
C4—C3—H3118.2C14—C13—H13B109.0
C5—C4—C3116.63 (14)H13A—C13—H13B107.8
C5—C4—C4i122.27 (17)C15—C14—C13114.95 (15)
C3—C4—C4i121.10 (17)C15—C14—H14A108.5
C6—C5—C4121.26 (14)C13—C14—H14A108.5
C6—C5—H5119.4C15—C14—H14B108.5
C4—C5—H5119.4C13—C14—H14B108.5
C5—C6—C1119.57 (13)H14A—C14—H14B107.5
C5—C6—C7134.08 (14)C14—C15—C16112.63 (16)
C1—C6—C7106.31 (14)C14—C15—H15A109.1
C8—C7—C12119.42 (15)C16—C15—H15A109.1
C8—C7—C6134.10 (16)C14—C15—H15B109.1
C12—C7—C6106.44 (14)C16—C15—H15B109.1
C9—C8—C7118.93 (18)H15A—C15—H15B107.8
C9—C8—H8120.5C15—C16—H16A109.5
C7—C8—H8120.5C15—C16—H16B109.5
C8—C9—C10120.59 (18)H16A—C16—H16B109.5
C8—C9—H9119.7C15—C16—H16C109.5
C10—C9—H9119.7H16A—C16—H16C109.5
C11—C10—C9122.02 (18)H16B—C16—H16C109.5
C11—C10—H10119.0
C12—N1—C1—C2179.62 (16)C1—C6—C7—C12−1.41 (16)
C13—N1—C1—C2−11.9 (2)C12—C7—C8—C90.0 (2)
C12—N1—C1—C60.15 (16)C6—C7—C8—C9177.40 (16)
C13—N1—C1—C6168.63 (13)C7—C8—C9—C100.1 (3)
N1—C1—C2—C3177.59 (14)C8—C9—C10—C110.0 (3)
C6—C1—C2—C3−3.0 (2)C9—C10—C11—C12−0.1 (3)
C1—C2—C3—C4−0.2 (2)C1—N1—C12—C11178.61 (16)
C2—C3—C4—C53.2 (2)C13—N1—C12—C1110.4 (3)
C2—C3—C4—C4i−176.60 (16)C1—N1—C12—C7−1.07 (17)
C3—C4—C5—C6−2.9 (2)C13—N1—C12—C7−169.27 (14)
C4i—C4—C5—C6176.86 (15)C10—C11—C12—N1−179.47 (16)
C4—C5—C6—C1−0.1 (2)C10—C11—C12—C70.2 (2)
C4—C5—C6—C7−177.52 (15)C8—C7—C12—N1179.62 (14)
N1—C1—C6—C5−177.26 (13)C6—C7—C12—N11.54 (17)
C2—C1—C6—C53.2 (2)C8—C7—C12—C11−0.1 (2)
N1—C1—C6—C70.79 (16)C6—C7—C12—C11−178.17 (14)
C2—C1—C6—C7−178.73 (14)C1—N1—C13—C14−69.5 (2)
C5—C6—C7—C8−1.4 (3)C12—N1—C13—C1496.88 (19)
C1—C6—C7—C8−179.08 (17)N1—C13—C14—C15−58.5 (2)
C5—C6—C7—C12176.24 (15)C13—C14—C15—C16−178.80 (17)
Symmetry code: (i) −x, −y+2, −z.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C7–C12 ring.
D—H···AD—HH···AD···AD—H···A
C15—H15B···Cgii0.972.983.838 (2)148
Symmetry code: (ii) −x+1/2, y−1/2, −z+1/2.
Hydrogen-bond geometry (Å, º) top
Cg is the centroid of the C7–C12 ring.
D—H···AD—HH···AD···AD—H···A
C15—H15B···Cgi0.972.983.838 (2)148
Symmetry code: (i) −x+1/2, y−1/2, −z+1/2.
 

Acknowledgements

CR and SS thank the Vice Chancellor and management of Kalasalingam University, Krishnankoil, for their support and encouragement.

References

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ISSN: 2056-9890
Volume 70| Part 12| December 2014| Pages o1283-o1284
doi:10.1107/S1600536814025367
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