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Acta Cryst. (2008). E64, o1712-o1713    [ doi:10.1107/S1600536808024756 ]

9-Methoxy-5-phenylsulfonyl-5H-benzo[b]carbazole

G. Chakkaravarthi, V. Dhayalan, A. K. Mohanakrishnan and V. Manivannan

Abstract top

In the title compound, C23H17NO3S, the mean plane of the benzo[b]carbazole ring system makes a dihedral angle of 77.17 (4)° with the phenyl ring. The S atom is in a distorted tetrahedral configuration. There are three intramolecular C-H...O interactions forming five- and six-membered rings with graph-set motifs S(5) and S(6), respectively.

Comment top

Carbazole derivatives exhibit antitumor (Itoigawa et al., 2000), antioxidative (Tachibana et al., 2001), anti-inflammatory and antimutagenic (Ramsewak et al., 1999) activities. These compounds are thermally and photochemically stable, which makes them useful materials for technological applications. For instance, the carbazole ring is easily funtionalized and covalently linked to other molecules (Diaz et al., 2002). This enables its use as a convenient building block for the design and synthesis of molecular glasses, which are widely studied as components of electroactive and photoactive materials (Zhang et al., 2004).

The geometric parameters in (I), (Fig. 1) agree with the reported similiar structures (Hökelek et al., 1998; Hosomi et al., 2000). The mean planes of the benzo[b]carbazole and phenyl ring form a dihedral angle of 77.17 (4)°. The N1—S1—C1 plane is almost orthogonal to carbazole ring [dihedral angle 89.54 (5)°] and phenyl ring [dihedral angle 86.02 (6)°]. The best plane of pyrrole ring N1/C7/C12/C13/C22 subtends a dihedral angle of 30.13 (8)° with sulfonyl group.

The average S—O, S—C, and S—N distances are comparable with those observed in similiar structures (Chakkaravarthi et al., 2007; Sankaranarayanan et al., 2000). The N—C bond lengths, namely N1—C7 and N1—C22 [1.4352 (17) & 1.4340 (16) Å] deviate slightly from the normal mean value reported in the literature (Allen et al., 1987). This indicates that the substitution of the phenylsulfonyl group at atom N1 results in lengthening of the C—N bond lengths. This may be due to the electron-withdrawing character of the phenylsulfonyl group (Govindasamy et al., 1998).

The S atom exhibits significant deviation from a regular tetrahedron, with the largest deviations being seen for the O1—S1—O2 [120.09 (9)°] and O1—S1—N1 [106.78 (7)°] angles. The widening of the angles may be due to repulsive interactions between the two short S=O bonds, similar to what is observed in related structures (Chakkaravarthi et al., 2008; Rodriguez et al., 1995). The sum of the bond angles around N1 [351.97°] indicate the sp2 hybridized state of the atom N, in the molecule.

The benzene ring C15—C20 is almost coplanar with methoxy group [torsion angle C23—O3—C17—C16 5.4 (2)°]. The torsion angles O1—S1—N1—C7 and O2—S1—N1—C22 [-44.62 (12)° and 41.56 (12)°, respectively] describe the syn conformation of the phenylsulfonyl group with respect to benzocarbazole ring system. This conformation is influenced by the intramolecular C—H··· O hydrogen bonds, C8—H8··· O1 and C21—H21···O2, involving sulfonyl atoms O1 and O2 (Table 1). The intramolecular hydrogen bonds form a six-membered ring with a graph-set motif of S(6) and a five-membered ring with a graph-set motif of S(5) (Etter et al., 1990).

Related literature top

For related literature, see: Allen et al. (1987); Chakkaravarthi et al. (2007, 2008); Diaz et al. (2002); Etter et al. (1990); Govindasamy et al. (1998); Hökelek et al. (1998); Hosomi et al. (2000); Itoigawa et al. (2000); Ramsewak et al. (1999); Rodriguez et al. (1995); Sankaranarayanan et al. (2000); Tachibana et al. (2001); Zhang et al. (2004).

Experimental top

To a solution of diethyl 2-((2-(bromomethyl)-1-(phenylsulfonyl)-1H-indol-3-yl)methylene) malonate (0.57 mmol) in dry 1,2-DCE (10 ml), ZnBr2 (1.15 mmol) and anisole (1.15 mmol) were added. The reaction mixture was then refluxed for 1 h under N2 atmosphere. It was then poured over ice-water (30 ml) containing 1 ml of concentrated HCl, extracted with Chloroform (2 X 10 ml) and dried (Na2SO4). The solvent was removed under vacuo, then crude products was purified by flash column chromatography (silica gel, 230–420 mesh, n-hexane/ethyl acetate 98:2) afforded the title compound suitable for X-ray analysis.

Refinement top

H atoms were positioned geometrically and refined using a riding model with C—H = 0.93 Å and Uiso(H) = 1.2Ueq(C) for aromatic H atoms and C—H = 0.96 Å and Uiso(H) = 1.5Ueq(C) for methyl H atoms.

Computing details top

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

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labeling scheme. Displacement ellipsoids are drawn at 50% probability level. H atoms are presented as a small spheres of arbitrary radius. Intramolecular H-bonds are shown as dashed lines.
9-Methoxy-5-phenylsulfonyl-5H-benzo[b]carbazole top
Crystal data top
C23H17NO3SZ = 2
Mr = 387.44F000 = 404
Triclinic, P1Dx = 1.399 Mg m−3
Hall symbol: -P 1Mo Kα radiation
λ = 0.71073 Å
a = 8.3608 (3) ÅCell parameters from 6534 reflections
b = 9.3103 (3) Åθ = 2.4–30.7º
c = 12.1754 (4) ŵ = 0.20 mm−1
α = 76.061 (2)ºT = 295 (2) K
β = 88.6800 (10)ºBlock, colourless
γ = 88.715 (2)º0.30 × 0.20 × 0.16 mm
V = 919.46 (5) Å3
Data collection top
Bruker Kappa APEX2
diffractometer		5739 independent reflections
Radiation source: fine-focus sealed tube4330 reflections with I > 2σ(I)
Monochromator: graphiteRint = 0.022
T = 295(2) Kθmax = 30.9º
ω and φ scansθmin = 2.3º
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		h = −12→12
Tmin = 0.909, Tmax = 0.969k = −12→13
23200 measured reflectionsl = −17→17
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)] = 0.042H-atom parameters constrained
wR(F2) = 0.134  w = 1/[σ2(Fo2) + (0.0653P)2 + 0.1785P]
where P = (Fo2 + 2Fc2)/3
S = 1.05(Δ/σ)max < 0.001
5739 reflectionsΔρmax = 0.29 e Å−3
254 parametersΔρmin = −0.35 e Å−3
Primary atom site location: structure-invariant direct methodsExtinction correction: none
Crystal data top
C23H17NO3Sγ = 88.715 (2)º
Mr = 387.44V = 919.46 (5) Å3
Triclinic, P1Z = 2
a = 8.3608 (3) ÅMo Kα
b = 9.3103 (3) ŵ = 0.20 mm−1
c = 12.1754 (4) ÅT = 295 (2) K
α = 76.061 (2)º0.30 × 0.20 × 0.16 mm
β = 88.6800 (10)º
Data collection top
Bruker Kappa APEX2
diffractometer		5739 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)		4330 reflections with I > 2σ(I)
Tmin = 0.909, Tmax = 0.969Rint = 0.022
23200 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.042254 parameters
wR(F2) = 0.134H-atom parameters constrained
S = 1.05Δρmax = 0.29 e Å−3
5739 reflectionsΔρmin = −0.35 e Å−3
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
S10.46793 (4)0.47800 (4)0.77672 (3)0.04613 (11)
O10.54144 (15)0.52427 (14)0.66788 (10)0.0629 (3)
O20.55193 (14)0.49026 (13)0.87398 (10)0.0595 (3)
O30.19450 (16)−0.22782 (14)1.37354 (9)0.0650 (3)
N10.42588 (14)0.30123 (12)0.79458 (9)0.0434 (2)
C10.28152 (18)0.56690 (14)0.77467 (12)0.0473 (3)
C20.2064 (2)0.57404 (18)0.87596 (15)0.0616 (4)
H20.25720.53910.94470.074*
C30.0533 (3)0.6349 (2)0.8715 (2)0.0820 (6)
H3−0.00030.64110.93800.098*
C4−0.0204 (3)0.6865 (2)0.7683 (3)0.0895 (7)
H4−0.12430.72460.76630.107*
C50.0581 (3)0.6822 (2)0.6692 (2)0.0845 (7)
H50.00850.71990.60040.101*
C60.2093 (2)0.62243 (18)0.67116 (15)0.0635 (4)
H60.26310.61910.60410.076*
C70.35493 (16)0.24535 (15)0.70734 (11)0.0419 (3)
C80.37507 (19)0.29073 (17)0.59112 (12)0.0512 (3)
H80.43630.37250.55790.061*
C90.3005 (2)0.20949 (19)0.52609 (13)0.0578 (4)
H90.31150.23770.44770.069*
C100.2101 (2)0.0875 (2)0.57509 (13)0.0602 (4)
H100.16200.03470.52940.072*
C110.1905 (2)0.04329 (18)0.69090 (13)0.0540 (4)
H110.1295−0.03880.72370.065*
C120.26309 (16)0.12316 (15)0.75771 (11)0.0427 (3)
C130.27196 (15)0.10092 (14)0.87926 (11)0.0409 (3)
C140.20944 (17)−0.00631 (16)0.96676 (12)0.0457 (3)
H140.1427−0.07770.95210.055*
C150.24777 (16)−0.00676 (15)1.07919 (11)0.0428 (3)
C160.19098 (19)−0.11947 (17)1.17162 (12)0.0504 (3)
H160.1228−0.19111.15890.060*
C170.23668 (18)−0.12252 (17)1.27913 (12)0.0498 (3)
C180.33749 (19)−0.01305 (17)1.29944 (12)0.0516 (3)
H180.3674−0.01601.37310.062*
C190.39146 (19)0.09670 (16)1.21281 (12)0.0486 (3)
H190.45720.16861.22800.058*
C200.34939 (16)0.10378 (14)1.09928 (11)0.0419 (3)
C210.41158 (17)0.21431 (15)1.00847 (12)0.0444 (3)
H210.47740.28741.02160.053*
C220.37207 (15)0.21053 (14)0.90096 (11)0.0398 (3)
C230.1076 (2)−0.3496 (2)1.35768 (15)0.0671 (5)
H23A0.0031−0.31641.33030.101*
H23B0.0974−0.42181.42840.101*
H23C0.1632−0.39321.30360.101*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0454 (2)0.04688 (19)0.04625 (18)−0.01263 (14)0.00349 (13)−0.01082 (13)
O10.0640 (7)0.0674 (7)0.0561 (6)−0.0223 (6)0.0174 (5)−0.0124 (5)
O20.0592 (7)0.0604 (6)0.0604 (6)−0.0184 (5)−0.0094 (5)−0.0151 (5)
O30.0758 (8)0.0647 (7)0.0478 (6)−0.0110 (6)−0.0011 (5)0.0005 (5)
N10.0449 (6)0.0423 (5)0.0435 (5)−0.0045 (5)0.0008 (4)−0.0115 (4)
C10.0536 (8)0.0348 (6)0.0532 (7)−0.0069 (5)0.0004 (6)−0.0094 (5)
C20.0682 (10)0.0485 (8)0.0638 (9)−0.0045 (7)0.0141 (8)−0.0062 (7)
C30.0766 (13)0.0555 (10)0.1082 (17)0.0014 (9)0.0332 (12)−0.0121 (10)
C40.0642 (12)0.0570 (11)0.145 (2)0.0128 (9)−0.0064 (14)−0.0210 (13)
C50.0874 (15)0.0581 (11)0.1115 (18)0.0186 (10)−0.0349 (14)−0.0258 (11)
C60.0789 (12)0.0500 (8)0.0634 (9)0.0034 (8)−0.0149 (8)−0.0160 (7)
C70.0396 (6)0.0440 (6)0.0445 (6)0.0008 (5)0.0015 (5)−0.0154 (5)
C80.0554 (8)0.0526 (8)0.0460 (7)−0.0061 (6)0.0064 (6)−0.0129 (6)
C90.0680 (10)0.0649 (9)0.0428 (7)−0.0058 (8)0.0028 (6)−0.0177 (6)
C100.0701 (11)0.0673 (10)0.0492 (8)−0.0115 (8)−0.0030 (7)−0.0243 (7)
C110.0595 (9)0.0555 (8)0.0503 (7)−0.0133 (7)0.0001 (6)−0.0182 (6)
C120.0406 (7)0.0464 (7)0.0429 (6)−0.0011 (5)0.0010 (5)−0.0146 (5)
C130.0369 (6)0.0435 (6)0.0434 (6)0.0003 (5)−0.0011 (5)−0.0129 (5)
C140.0434 (7)0.0473 (7)0.0474 (7)−0.0078 (5)−0.0011 (5)−0.0127 (5)
C150.0395 (6)0.0437 (6)0.0445 (6)0.0013 (5)−0.0003 (5)−0.0098 (5)
C160.0492 (8)0.0508 (7)0.0490 (7)−0.0055 (6)0.0005 (6)−0.0076 (6)
C170.0495 (8)0.0499 (7)0.0464 (7)0.0041 (6)0.0003 (6)−0.0051 (6)
C180.0587 (9)0.0516 (8)0.0447 (7)0.0086 (6)−0.0078 (6)−0.0121 (6)
C190.0534 (8)0.0458 (7)0.0486 (7)0.0031 (6)−0.0076 (6)−0.0149 (6)
C200.0410 (7)0.0411 (6)0.0446 (6)0.0053 (5)−0.0027 (5)−0.0126 (5)
C210.0455 (7)0.0404 (6)0.0490 (7)−0.0019 (5)−0.0039 (5)−0.0133 (5)
C220.0373 (6)0.0385 (6)0.0438 (6)0.0012 (5)0.0000 (5)−0.0107 (5)
C230.0704 (11)0.0616 (10)0.0617 (10)−0.0096 (8)0.0024 (8)0.0004 (8)
Geometric parameters (Å, °) top
S1—O21.4197 (11)C10—C111.377 (2)
S1—O11.4208 (11)C10—H100.9300
S1—N11.6521 (12)C11—C121.385 (2)
S1—C11.7461 (16)C11—H110.9300
O3—C171.3641 (17)C12—C131.4475 (18)
O3—C231.414 (2)C13—C141.3748 (18)
N1—C221.4340 (16)C13—C221.4107 (18)
N1—C71.4352 (17)C14—C151.4120 (19)
C1—C21.386 (2)C14—H140.9300
C1—C61.388 (2)C15—C201.418 (2)
C2—C31.385 (3)C15—C161.4219 (19)
C2—H20.9300C16—C171.366 (2)
C3—C41.386 (3)C16—H160.9300
C3—H30.9300C17—C181.407 (2)
C4—C51.369 (3)C18—C191.356 (2)
C4—H40.9300C18—H180.9300
C5—C61.368 (3)C19—C201.4200 (19)
C5—H50.9300C19—H190.9300
C6—H60.9300C20—C211.4146 (19)
C7—C81.3833 (19)C21—C221.3662 (18)
C7—C121.3933 (19)C21—H210.9300
C8—C91.386 (2)C23—H23A0.9600
C8—H80.9300C23—H23B0.9600
C9—C101.381 (2)C23—H23C0.9600
C9—H90.9300
O2—S1—O1119.66 (7)C10—C11—H11120.6
O2—S1—N1106.69 (6)C12—C11—H11120.6
O1—S1—N1106.78 (7)C11—C12—C7119.86 (13)
O2—S1—C1109.52 (7)C11—C12—C13131.94 (13)
O1—S1—C1108.60 (8)C7—C12—C13108.10 (12)
N1—S1—C1104.52 (6)C14—C13—C22120.69 (12)
C17—O3—C23117.30 (13)C14—C13—C12131.56 (13)
C22—N1—C7107.12 (10)C22—C13—C12107.65 (11)
C22—N1—S1122.77 (9)C13—C14—C15119.27 (13)
C7—N1—S1122.08 (9)C13—C14—H14120.4
C2—C1—C6121.82 (16)C15—C14—H14120.4
C2—C1—S1119.46 (12)C14—C15—C20119.23 (12)
C6—C1—S1118.64 (13)C14—C15—C16120.91 (13)
C3—C2—C1117.85 (18)C20—C15—C16119.81 (13)
C3—C2—H2121.1C17—C16—C15119.97 (14)
C1—C2—H2121.1C17—C16—H16120.0
C2—C3—C4120.2 (2)C15—C16—H16120.0
C2—C3—H3119.9O3—C17—C16125.14 (15)
C4—C3—H3119.9O3—C17—C18114.46 (13)
C5—C4—C3120.8 (2)C16—C17—C18120.40 (14)
C5—C4—H4119.6C19—C18—C17120.70 (14)
C3—C4—H4119.6C19—C18—H18119.6
C6—C5—C4120.1 (2)C17—C18—H18119.6
C6—C5—H5119.9C18—C19—C20121.16 (14)
C4—C5—H5119.9C18—C19—H19119.4
C5—C6—C1119.11 (19)C20—C19—H19119.4
C5—C6—H6120.4C21—C20—C15120.89 (12)
C1—C6—H6120.4C21—C20—C19121.12 (13)
C8—C7—C12121.66 (13)C15—C20—C19117.95 (13)
C8—C7—N1129.40 (13)C22—C21—C20118.05 (13)
C12—C7—N1108.81 (11)C22—C21—H21121.0
C7—C8—C9117.38 (14)C20—C21—H21121.0
C7—C8—H8121.3C21—C22—C13121.87 (12)
C9—C8—H8121.3C21—C22—N1129.70 (12)
C10—C9—C8121.48 (14)C13—C22—N1108.31 (11)
C10—C9—H9119.3O3—C23—H23A109.5
C8—C9—H9119.3O3—C23—H23B109.5
C11—C10—C9120.74 (15)H23A—C23—H23B109.5
C11—C10—H10119.6O3—C23—H23C109.5
C9—C10—H10119.6H23A—C23—H23C109.5
C10—C11—C12118.87 (14)H23B—C23—H23C109.5
O2—S1—N1—C2241.56 (12)C11—C12—C13—C14−0.7 (3)
O1—S1—N1—C22170.62 (11)C7—C12—C13—C14−176.98 (14)
C1—S1—N1—C22−74.41 (12)C11—C12—C13—C22175.59 (15)
O2—S1—N1—C7−173.68 (10)C7—C12—C13—C22−0.70 (15)
O1—S1—N1—C7−44.62 (12)C22—C13—C14—C15−0.6 (2)
C1—S1—N1—C770.35 (11)C12—C13—C14—C15175.24 (13)
O2—S1—C1—C2−29.51 (14)C13—C14—C15—C200.2 (2)
O1—S1—C1—C2−161.84 (12)C13—C14—C15—C16−177.31 (13)
N1—S1—C1—C284.48 (13)C14—C15—C16—C17176.37 (13)
O2—S1—C1—C6153.51 (12)C20—C15—C16—C17−1.2 (2)
O1—S1—C1—C621.18 (14)C23—O3—C17—C165.4 (2)
N1—S1—C1—C6−92.51 (13)C23—O3—C17—C18−173.41 (14)
C6—C1—C2—C31.9 (2)C15—C16—C17—O3−177.59 (14)
S1—C1—C2—C3−174.97 (13)C15—C16—C17—C181.2 (2)
C1—C2—C3—C4−0.1 (3)O3—C17—C18—C19178.60 (14)
C2—C3—C4—C5−1.8 (3)C16—C17—C18—C19−0.3 (2)
C3—C4—C5—C61.9 (3)C17—C18—C19—C20−0.6 (2)
C4—C5—C6—C1−0.1 (3)C14—C15—C20—C210.4 (2)
C2—C1—C6—C5−1.9 (3)C16—C15—C20—C21177.97 (12)
S1—C1—C6—C5175.06 (14)C14—C15—C20—C19−177.30 (12)
C22—N1—C7—C8−176.94 (14)C16—C15—C20—C190.3 (2)
S1—N1—C7—C833.57 (19)C18—C19—C20—C21−177.08 (13)
C22—N1—C7—C12−1.03 (14)C18—C19—C20—C150.6 (2)
S1—N1—C7—C12−150.52 (10)C15—C20—C21—C22−0.6 (2)
C12—C7—C8—C9−0.2 (2)C19—C20—C21—C22177.01 (12)
N1—C7—C8—C9175.27 (14)C20—C21—C22—C130.2 (2)
C7—C8—C9—C10−0.3 (3)C20—C21—C22—N1−175.36 (12)
C8—C9—C10—C110.4 (3)C14—C13—C22—C210.4 (2)
C9—C10—C11—C12−0.1 (3)C12—C13—C22—C21−176.35 (12)
C10—C11—C12—C7−0.4 (2)C14—C13—C22—N1176.82 (12)
C10—C11—C12—C13−176.35 (15)C12—C13—C22—N10.06 (14)
C8—C7—C12—C110.5 (2)C7—N1—C22—C21176.62 (13)
N1—C7—C12—C11−175.75 (13)S1—N1—C22—C21−34.15 (19)
C8—C7—C12—C13177.36 (13)C7—N1—C22—C130.58 (14)
N1—C7—C12—C131.07 (15)S1—N1—C22—C13149.81 (10)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O10.932.362.951 (2)121
C21—H21···O20.932.362.9460 (18)121
C6—H6···O10.932.542.906 (2)104
Table 1
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
C8—H8···O10.932.362.951 (2)121
C21—H21···O20.932.362.9460 (18)121
C6—H6···O10.932.542.906 (2)104
Acknowledgements top

The authors acknowledge the Sophisticated Analytical Instrument Facility, Indian Institute of Technology, Madras, for the data collection.

references
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