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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 64| Part 9| September 2008| Page o1681
doi:10.1107/S1600536808024318

9-Ethyl-2,3-di­hydro-9H-carbazol-4(1H)-one

S. Murugavel,a G. Ganesh,b A. Subbiah Pandi,c* Ramalingam Murugand and S. Sriman Narayanand

aDepartment of Physics, Thanthai Periyar Government Institute of Technology, Vellore 632 002, India, bDepartment of Physics, SMK Fomra Institute of Technology, Thaiyur, Chennai 603 103, India, cDepartment of Physics, Presidency College (Autonomous), Chennai 600 005, India, and dDepartment of Analytical Chemistry, University of Madras, Guindy Campus, Chennai 600 025, India
*Correspondence e-mail: a_spandian@yahoo.com

(Received 11 July 2008; accepted 30 July 2008; online 6 August 2008)

In the title compound, C28H30N2O2, the cyclo­hexene ring system adopts a sofa conformation. The crystal structure is stabilized by C—H⋯O inter­actions between methyl H atoms of the ethyl substituents and the O atoms of carbonyl groups of adjacent mol­ecules, and by an inter­molecular carbon­yl–carbonyl inter­actions [3.207 (2) Å]

Related literature

For related literature, see: Abraham (1975[Abraham, D. J. (1975). The Catharanthus Alkaloids, edited by W. I. Taylor & N. R. Farnsworth, ch. 7 and 8. New York: Marcel Decker.]); Govindasamy et al. (1999[Govindasamy, L., Velmurugan, D. & Ramasubbu, N. (1999). Cryst. Res. Technol. 34, 1229-1234.]); Hewlins et al. (1984[Hewlins, J. M. E., Oliveira- Campos, A. M. & Shannon, P. V. R. (1984). Synthesis, 289-302.]); Kansal et al. (1986[Kansal, V. K. & Potier, P. (1986). Tetrahedron, 42, 2389-2408.]); Mi et al. (2003[Mi, B. X., Wang, P. F., Liu, M. W., Kwong, H. L., Wong, N. B., Lee, C. S. & Lee, S. T. (2003). Chem Mater. 15, 3148-3151.]); Nardelli (1983[Nardelli, M. (1983). Acta Cryst. C39, 1141-1142.]); Phillipson & Zenk (1980[Phillipson, J. D. & Zenk, M. H. (1980). Editors. Indole and Biogenitically Related Alkaloids, Ch. 3. New York: Academic Press.]); Saxton (1983[Saxton, J. E. (1983). Editor. Heterocyclic Compounds, Vol. 25, The Monoterpenoid Indole Alkaloids, ch. 8 and 11. New York: Wiley.]); Allen et al. (1998[Allen, F. H., Baalham, C. A., Lommerse, J. P. M. & Raithby, P. R. (1998). Acta Cryst. B54, 320-329.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Mohanakrishnan & Srinivasasan (1995[Mohanakrishnan, A. K. & Srinivasasan, P. C. (1995). J. Org. Chem. 60, 1939-1946.][Mohanakrishnan, A. K. & Srinivasasan, P. C. (1995). Indian J. Chem. Sect. B, 35, 838-841.], 1995[Mohanakrishnan, A. K. & Srinivasasan, P. C. (1995). J. Org. Chem. 60, 1939-1946.][Mohanakrishnan, A. K. & Srinivasasan, P. C. (1995). Indian J. Chem. Sect. B, 35, 838-841.]).

[Scheme 1]

Experimental

Crystal data

  • C14H15NO

  • Mr = 213.27

  • Monoclinic, P 21 /n

  • a = 8.3742 (6) Å

  • b = 17.033 (1) Å

  • c = 8.6083 (5) Å

  • β = 116.432 (3)°

  • V = 1099.51 (12) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 293 (2) K

  • 0.21 × 0.19 × 0.17 mm
Data collection

  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: none

  • 11070 measured reflections

  • 2334 independent reflections

  • 1898 reflections with I > 2σ(I)

  • Rint = 0.029
Refinement

  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.105

  • S = 1.03

  • 2334 reflections

  • 146 parameters

  • H-atom parameters constrained

  • Δρmax = 0.15 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C14—H14A⋯O1i 0.96 2.60 3.549 (2) 170
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: APEX2; data reduction: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); 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.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808024318/lx2064sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808024318/lx2064Isup2.hkl

checkCIF report


Comment top

Carbazole derivatives exhibit good charge transfer and hole transporting properties, which are being explored for a multitude of optoelectronic and photocatalytic applications, including organic light emitting diodes (OLEDs) (Mi et al., 2003). In carbazole derivatives, the preliminary study shows that the presence of oxygenated substituents increases their biological activity (Hewlins, Oliveira-Campos & Shannon, 1984). The 2,3-disubstituted indoles have been used as bidentate synthons for the synthesis of various medicinally important carbazole alkaloids (Mohanakrishnan & Srinivasan, 1995). Intercalation between the base pairs in DNA has been implicated for their anticancer activity. It was conceived that the benzo[b] carbazoles as isosteric analogs of pyrido[4,3-b]carbazoles, with oxygenated D-ring could mimic the anti-cancer activity of ellipticine. So it was of interest to study the anticancer activity of D-ring oxygenated benzo[b]carbazoles as it is believed that these molecules could form a stable intercalation complex with DNA (Kansal & Potier, 1986). Tetrahydrocarbazole derivatives are present in the framework of indole-type alkaloids of biological interest (Phillipson & Zenk, 1980; Saxton, 1983; Abraham, 1975). Here we report the crystal and molecular structure of the title compound, 9-ethyl-1,2,3-trihydrocarbazol-4(2H)-one (Fig. 1).

The planarities of rings A and C are fairly good. The bond lengths C8—O1, N1—C5 and N1—C12 are normal and comparable with the corresponding values observed in the related structure. (Govindasamy et al., 1999). The atom O1 deviates by -0.033 (1) Å from the least-squares plane of the ring C. The cyclohexane ring of the carbazole moiety adopts sofa conformation, with lowest displacement asymmetric parameter (Nardelli, 1983), ΔCs(C7) = 2.26 (1) °, and puckering parameter (Cremer & Popple, 1975) q2 = 0.373 (2) Å and ϕ = 359.1 (2) °. The crystal packing (Fig. 2) is stabilized by a C—H···O interaction between a methyl H atom of the ethyl substituent and the oxygen of the carbonyl group of an adjacent molecule, with a C14—H14A···O1i separation of 2.60 Å (Fig. 2 and Table 1; symmetry code as in Fig. 2). The molecular packing (Fig. 2) is further stabilized by a type-II carbonyl-carbonyl interaction (Allen et al., 1998), with C8···O1ii and O1···C8ii distance of 3.207 (2) Å (symmetry code as in Fig. 2).

Related literature top

For related literature, see: Abraham (1975); Govindasamy et al. (1999); Hewlins et al. (1984); Kansal et al. (1986); Mi et al. (2003); Nardelli (1983); Phillipson & Zenk (1980); Saxton (1983); Allen et al. (1998); Cremer & Popple (1975); Mohanakrishnan & Srinivasasan (1995, 1995).

Experimental top

A mixture of (0.5 g, 1.0 mol), ethyl bromide (0.18 g, 1.0 mol) and potassium carbonate (2.0 g) in 1,4-dioxane (10 ml) was refluxed for ca. 5.0 h. Then the reaction mixture was poured in water and then the crude solid was filtered. Single crystals suitable for X-ray diffraction were obtained by slow evaporation of a solution of the title compound in ethanol at room temperature.

Refinement top

All H atoms were fixed geometrically and allowed to ride on their parent C atoms, with C—H distances fixed in the range 0.93–0.98 Å with Uiso(H) = 1.5Ueq(C) for methyl H 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: APEX2 (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Ferrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The molecular structure of title compound showing 30% probability displacement ellipsoids.
[Figure 2] Fig. 2. C—H···O and C···O interaction(dotted lines) in the title compound. [Symmetry code: (i) -x+1, -y+1, -z+1; (ii) -x+1, -y+1, -z+2; (iii) x, y, z-1.]
9-Ethyl-2,3-dihydro-9H-carbazol-4(1H)-one top
Crystal data top
C14H15NOF(000) = 456
Mr = 213.27Dx = 1.288 Mg m−3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2850 reflections
a = 8.3742 (6) Åθ = 20.0–26.8°
b = 17.033 (1) ŵ = 0.08 mm−1
c = 8.6083 (5) ÅT = 293 K
β = 116.432 (3)°Block, colourless
V = 1099.51 (12) Å30.21 × 0.19 × 0.17 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1898 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.029
Graphite monochromatorθmax = 26.8°, θmin = 2.4°
Detector resolution: 10 pixels mm-1h = −10→10
ω scansk = −21→21
11070 measured reflectionsl = −10→10
2334 independent reflections
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)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0497P)2 + 0.2126P]
where P = (Fo2 + 2Fc2)/3
2334 reflections(Δ/σ)max < 0.001
146 parametersΔρmax = 0.15 e Å−3
0 restraintsΔρmin = −0.20 e Å−3
Crystal data top
C14H15NOV = 1099.51 (12) Å3
Mr = 213.27Z = 4
Monoclinic, P21/nMo Kα radiation
a = 8.3742 (6) ŵ = 0.08 mm−1
b = 17.033 (1) ÅT = 293 K
c = 8.6083 (5) Å0.21 × 0.19 × 0.17 mm
β = 116.432 (3)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer		1898 reflections with I > 2σ(I)
11070 measured reflectionsRint = 0.029
2334 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.105H-atom parameters constrained
S = 1.03Δρmax = 0.15 e Å−3
2334 reflectionsΔρmin = −0.20 e Å−3
146 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.

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 > 2sigma(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
C10.41850 (18)0.62548 (8)0.62150 (18)0.0419 (3)
H10.52000.63880.72170.050*
C20.3279 (2)0.68137 (8)0.4981 (2)0.0506 (4)
H20.36850.73300.51600.061*
C30.1766 (2)0.66211 (9)0.3472 (2)0.0527 (4)
H30.11860.70110.26590.063*
C40.11103 (19)0.58687 (8)0.31534 (17)0.0457 (3)
H40.01020.57410.21400.055*
C50.20092 (16)0.53077 (8)0.44009 (15)0.0359 (3)
C60.35512 (16)0.54847 (7)0.59327 (15)0.0343 (3)
C70.40707 (16)0.47683 (7)0.69054 (15)0.0350 (3)
C80.55752 (16)0.45924 (8)0.85455 (16)0.0392 (3)
C90.56815 (19)0.37540 (9)0.91598 (19)0.0490 (4)
H9A0.62180.37521.04170.059*
H9B0.64620.34610.88110.059*
C100.38967 (19)0.33358 (9)0.84713 (19)0.0509 (4)
H10A0.31780.35740.89700.061*
H10B0.40910.27900.88320.061*
C110.28888 (19)0.33744 (8)0.65050 (19)0.0465 (3)
H11A0.34760.30490.59890.056*
H11B0.16820.31820.61230.056*
C120.28502 (16)0.42042 (7)0.59547 (16)0.0364 (3)
C130.01251 (17)0.41064 (8)0.30768 (17)0.0431 (3)
H13A−0.07910.44830.24000.052*
H13B−0.03880.37400.35930.052*
C140.0697 (2)0.36655 (11)0.1896 (2)0.0595 (4)
H14A0.12500.40220.14180.089*
H14B−0.03260.34290.09730.089*
H14C0.15340.32640.25430.089*
N10.16080 (13)0.45195 (6)0.44527 (13)0.0372 (3)
O10.67261 (13)0.50731 (6)0.93817 (12)0.0530 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0411 (7)0.0438 (7)0.0420 (7)−0.0052 (6)0.0196 (6)−0.0026 (6)
C20.0601 (9)0.0400 (7)0.0568 (9)−0.0026 (7)0.0307 (8)0.0030 (6)
C30.0602 (9)0.0474 (8)0.0506 (8)0.0113 (7)0.0248 (7)0.0144 (7)
C40.0426 (8)0.0533 (8)0.0364 (7)0.0082 (6)0.0134 (6)0.0042 (6)
C50.0341 (6)0.0409 (7)0.0335 (6)0.0027 (5)0.0158 (5)−0.0019 (5)
C60.0321 (6)0.0397 (7)0.0331 (6)0.0006 (5)0.0164 (5)−0.0013 (5)
C70.0314 (6)0.0387 (7)0.0336 (6)0.0000 (5)0.0133 (5)−0.0012 (5)
C80.0312 (6)0.0514 (8)0.0344 (6)0.0007 (6)0.0140 (5)−0.0014 (6)
C90.0422 (8)0.0549 (9)0.0430 (7)0.0080 (6)0.0128 (6)0.0090 (6)
C100.0509 (9)0.0447 (8)0.0546 (8)0.0030 (6)0.0213 (7)0.0113 (6)
C110.0443 (8)0.0370 (7)0.0535 (8)−0.0003 (6)0.0176 (6)−0.0008 (6)
C120.0327 (6)0.0393 (7)0.0362 (6)0.0019 (5)0.0145 (5)−0.0018 (5)
C130.0311 (7)0.0491 (8)0.0415 (7)−0.0042 (6)0.0093 (5)−0.0086 (6)
C140.0462 (9)0.0782 (11)0.0497 (8)−0.0101 (8)0.0172 (7)−0.0251 (8)
N10.0318 (5)0.0389 (6)0.0346 (6)−0.0001 (4)0.0092 (4)−0.0041 (4)
O10.0399 (5)0.0643 (7)0.0420 (5)−0.0092 (5)0.0067 (4)−0.0038 (5)
Geometric parameters (Å, º) top
C1—C21.376 (2)C9—H9A0.9700
C1—C61.395 (2)C9—H9B0.9700
C1—H10.9300C10—C111.520 (2)
C2—C31.391 (2)C10—H10A0.9700
C2—H20.9300C10—H10B0.9700
C3—C41.373 (2)C11—C121.486 (2)
C3—H30.9300C11—H11A0.9700
C4—C51.383 (2)C11—H11B0.9700
C4—H40.9300C12—N11.358 (2)
C5—N11.390 (2)C13—N11.460 (2)
C5—C61.408 (2)C13—C141.503 (2)
C6—C71.434 (2)C13—H13A0.9700
C7—C121.376 (2)C13—H13B0.9700
C7—C81.445 (2)C14—H14A0.9600
C8—O11.225 (2)C14—H14B0.9600
C8—C91.512 (2)C14—H14C0.9600
C9—C101.518 (2)
C2—C1—C6118.67 (13)C9—C10—C11112.13 (12)
C2—C1—H1120.7C9—C10—H10A109.2
C6—C1—H1120.7C11—C10—H10A109.2
C1—C2—C3121.19 (14)C9—C10—H10B109.2
C1—C2—H2119.4C11—C10—H10B109.2
C3—C2—H2119.4H10A—C10—H10B107.9
C4—C3—C2121.57 (13)C12—C11—C10108.58 (11)
C4—C3—H3119.2C12—C11—H11A110.0
C2—C3—H3119.2C10—C11—H11A110.0
C3—C4—C5117.31 (13)C12—C11—H11B110.0
C3—C4—H4121.3C10—C11—H11B110.0
C5—C4—H4121.3H11A—C11—H11B108.4
C4—C5—N1129.54 (12)N1—C12—C7109.97 (11)
C4—C5—C6122.31 (12)N1—C12—C11125.32 (11)
N1—C5—C6108.12 (10)C7—C12—C11124.71 (11)
C1—C6—C5118.94 (12)N1—C13—C14112.16 (11)
C1—C6—C7134.87 (12)N1—C13—H13A109.2
C5—C6—C7106.15 (11)C14—C13—H13A109.2
C12—C7—C6107.16 (11)N1—C13—H13B109.2
C12—C7—C8122.03 (12)C14—C13—H13B109.2
C6—C7—C8130.79 (12)H13A—C13—H13B107.9
O1—C8—C7123.48 (13)C13—C14—H14A109.5
O1—C8—C9121.17 (12)C13—C14—H14B109.5
C7—C8—C9115.32 (11)H14A—C14—H14B109.5
C8—C9—C10114.35 (11)C13—C14—H14C109.5
C8—C9—H9A108.7H14A—C14—H14C109.5
C10—C9—H9A108.7H14B—C14—H14C109.5
C8—C9—H9B108.7C12—N1—C5108.60 (10)
C10—C9—H9B108.7C12—N1—C13126.60 (11)
H9A—C9—H9B107.6C5—N1—C13124.77 (11)
C6—C1—C2—C3−0.4 (2)C7—C8—C9—C10−26.10 (17)
C1—C2—C3—C40.3 (2)C8—C9—C10—C1153.43 (17)
C2—C3—C4—C50.3 (2)C9—C10—C11—C12−50.05 (16)
C3—C4—C5—N1177.12 (13)C6—C7—C12—N10.19 (14)
C3—C4—C5—C6−0.9 (2)C8—C7—C12—N1−178.24 (11)
C2—C1—C6—C5−0.11 (18)C6—C7—C12—C11−179.46 (12)
C2—C1—C6—C7−177.39 (13)C8—C7—C12—C112.1 (2)
C4—C5—C6—C10.80 (18)C10—C11—C12—N1−155.43 (12)
N1—C5—C6—C1−177.59 (11)C10—C11—C12—C724.16 (19)
C4—C5—C6—C7178.79 (12)C7—C12—N1—C50.06 (14)
N1—C5—C6—C70.40 (13)C11—C12—N1—C5179.71 (12)
C1—C6—C7—C12177.16 (14)C7—C12—N1—C13178.10 (11)
C5—C6—C7—C12−0.36 (13)C11—C12—N1—C13−2.2 (2)
C1—C6—C7—C8−4.6 (2)C4—C5—N1—C12−178.53 (13)
C5—C6—C7—C8177.88 (12)C6—C5—N1—C12−0.29 (13)
C12—C7—C8—O1176.58 (12)C4—C5—N1—C133.4 (2)
C6—C7—C8—O1−1.4 (2)C6—C5—N1—C13−178.38 (11)
C12—C7—C8—C9−1.59 (18)C14—C13—N1—C12−80.84 (17)
C6—C7—C8—C9−179.60 (13)C14—C13—N1—C596.90 (16)
O1—C8—C9—C10155.68 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C14—H14A···O1i0.962.603.549 (2)170
Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formulaC14H15NO
Mr213.27
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)8.3742 (6), 17.033 (1), 8.6083 (5)
β (°) 116.432 (3)
V (Å3)1099.51 (12)
Z4
Radiation typeMo Kα
µ (mm−1)0.08
Crystal size (mm)0.21 × 0.19 × 0.17
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correction–
No. of measured, independent and
observed [I > 2σ(I)] reflections		11070, 2334, 1898
Rint0.029
(sin θ/λ)max (Å−1)0.634
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.040, 0.105, 1.03
No. of reflections2334
No. of parameters146
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.15, −0.20

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Ferrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C14—H14A···O1i0.962.603.549 (2)169.7
Symmetry code: (i) −x+1, −y+1, −z+1.
 

Acknowledgements

The authors are greatful to Dr S. Pandi, Head of the Department of Physics, Presidency College (Autonomous), Chennai, for providing the necessary facilities. Dr Babu Varghese, SAIF, IIT, Madras, India, is thanked for collecting the X-ray intensity data.

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ISSN: 2056-9890
Volume 64| Part 9| September 2008| Page o1681
doi:10.1107/S1600536808024318
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