2-Chloro-7,8,9,10-tetra­hydro­cyclo­hepta­[b]indol-6(5H)-one

Archana, R.; Yamuna, E.; Rajendra Prasad, K.J.; Thiruvalluvar, A.; Butcher, R.J.; Gupta, S.K.; Öztürk Yildirim, S.

doi:10.1107/S1600536812022945

organic compounds

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ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page o1887

doi:10.1107/S1600536812022945

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2-Chloro-7,8,9,10-tetrahydrocyclohepta[b]indol-6(5H)-one

R. Archana,^a E. Yamuna,^b K. J. Rajendra Prasad,^b A. Thiruvalluvar,^a ^* R. J. Butcher,^c Sushil K. Gupta ^d and Sema Öztürk Yildirim ^e,^f

^aPG Research Department of Physics, Rajah Serfoji Government College (Autonomous), Thanjavur 613 005, Tamilnadu, India, ^bDepartment of Chemistry, Bharathiar University, Coimbatore 641 046, Tamilnadu, India, ^cDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA, ^dSchool of Studies in Chemistry, Jiwaji University, Gwalior 474 011, MP, India, ^eChemistry Department, Howard University, Washington, DC 20059, USA, and ^fDepartment of Physics, Faculty of Sciences, Erciyes University, 38039 Kayseri, Turkey
^*Correspondence e-mail: thiruvalluvar.a@gmail.com

(Received 18 May 2012; accepted 19 May 2012; online 26 May 2012)

In the title molecule, C₁₃H₁₂ClNO, the dihedral angle between the benzene and pyrrole rings is 1.38 (9)°. The cycloheptene ring adopts a distorted twist chair and sofa conformation. Intermolecular N—H⋯O hydrogen bonds form an R₂²(10) loop in the crystal packing. Further, weak C—H⋯O and C—H⋯π (involving the benzene ring) interactions are found in the crystal structure.

Related literature

For the biological activity of indole derivatives, see: Gribble (2000 ); Knölker & Reddy (2002 ); Kawasaki & Higuchi (2005 ); Bennasar et al. (1993 ); Hong et al. (2006 ); Lacoume et al. (1972 ); Joseph et al. (1998 , 2000 ). For related crystallographic studies of cyclohept[b]indoles, see: Archana et al. (2010 , 2011 ). For hydrogen-bond motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₃H₁₂ClNO
M_r = 233.69
Monoclinic, P 2₁ /n
a = 11.6354 (4) Å
b = 6.3798 (2) Å
c = 14.4513 (5) Å
β = 92.767 (3)°
V = 1071.49 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.33 mm⁻¹
T = 150 K
0.40 × 0.30 × 0.30 mm

Data collection

Agilent Xcalibur Ruby Gemini diffractometer
Absorption correction: multi-scan CrysAlis PRO (Agilent, 2011 ) T_min = 0.879, T_max = 0.907
4977 measured reflections
2274 independent reflections
1836 reflections with I > 2σ(I)
R_int = 0.026

Refinement

R[F² > 2σ(F²)] = 0.039
wR(F²) = 0.096
S = 1.04
2274 reflections
149 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.26 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 is the centroid of the C1–C4,C4A,C10B ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N5—H5⋯O6ⁱ	0.837 (19)	2.13 (2)	2.904 (2)	153.2 (19)
C9—H9A⋯O6ⁱⁱ	0.99	2.55	3.228 (2)	125
C7—H7A⋯Cg2ⁱⁱⁱ	0.99	2.95	3.7969 (19)	144
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) x, y-1, z; (iii) -x+1, -y, -z+1.

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812022945/tk5099sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812022945/tk5099Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812022945/tk5099Isup3.cdx

Supporting information file. DOI: 10.1107/S1600536812022945/tk5099Isup4.cml

checkCIF report

Comment top

An indole nucleus coupled with prenylated indoles, carbazoles, indoloquinoline and cyclohept[b]indole alkaloids show high levels of biological activities including anti-fungal, anti-bacterial, anti-tumour and anti-HIV activities, as well as DNA interaction properties (Gribble, 2000; Knölker & Reddy, 2002; Kawasaki & Higuchi, 2005; Bennasar et al., 1993; Hong et al., 2006; Lacoume et al., 1972; Joseph et al., 1998; Joseph et al., 2000). Recently, we reported related crystallographic studies for some cyclohept[b]indoles from our laboratory (Archana et al., 2010; Archana et al., 2011).

In the title molecule, Fig. 1, the dihedral angle between the benzene and pyrrole rings is 1.38 (9)°. The cycloheptene ring adopts a distorted twist chair and sofa conformation. Intermolecular N5—H5···O6 hydrogen bonds form a R²₂(10) (Bernstein et al., 1995) rings in the crystal structure. A weak C9—H9A···O6 intermolecular hydrogen bond along with a C7—H7A···π interaction, involving the benzene (C1–C4,C4A,C10B) ring, are also found in the crystal structure, Fig. 2 and Table 1.

Related literature top

For the biological activity of indole derivatives, see: Gribble (2000); Knölker & Reddy (2002); Kawasaki & Higuchi (2005); Bennasar et al. (1993); Hong et al. (2006); Lacoume et al. (1972); Joseph et al. (1998, 2000). For related crystallographic studies of cyclohept[b]indoles, see: Archana et al. (2010, 2011). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

A solution of 2-(2-(4-chlorophenyl)hydrazono)cycloheptanone (0.486 g, 0.001 mol) in a mixture of acetic acid (20 ml) and hydrochloric acid (5 ml) was refluxed on an oil bath pre-heated to 398 K for 2 h. The contents were then cooled and poured onto cold water with stirring. The brown solid which was separated by passing through a column of silica gel and eluted with (98:2, v/v) petroleum ether-ethyl acetate mixture yielded the title compound (0.167 g, 72%). This was recrystallized from ethanol.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. The crystal structure of (I), viewed down the b axis, showing the formation of a R²₂(10) ring by N—H···O hydrogen bonding (dashed lines). H atoms not involved in hydrogen bonding have been omitted.

2-Chloro-7,8,9,10-tetrahydrocyclohepta[b]indol-6(5H)-one top

Crystal data top

C₁₃H₁₂ClNO	F(000) = 488
M_r = 233.69	D_x = 1.449 Mg m⁻³
Monoclinic, P2₁/n	Melting point: 389 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 11.6354 (4) Å	Cell parameters from 2495 reflections
b = 6.3798 (2) Å	θ = 3.2–28.4°
c = 14.4513 (5) Å	µ = 0.33 mm⁻¹
β = 92.767 (3)°	T = 150 K
V = 1071.49 (6) Å³	Block, colourless
Z = 4	0.40 × 0.30 × 0.30 mm

Data collection top

Agilent Xcalibur Ruby Gemini diffractometer	2274 independent reflections
Radiation source: Enhance (Mo) X-ray Source	1836 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.026
Detector resolution: 10.5081 pixels mm^-1	θ_max = 28.4°, θ_min = 3.5°
ω scans	h = −14→15
Absorption correction: multi-scan CrysAlis PRO (Agilent, 2011)	k = −8→7
T_min = 0.879, T_max = 0.907	l = −12→19
4977 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.039	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ²(F_o²) + (0.0373P)² + 0.4689P] where P = (F_o² + 2F_c²)/3
2274 reflections	(Δ/σ)_max = 0.001
149 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.26 e Å⁻³

Crystal data top

C₁₃H₁₂ClNO	V = 1071.49 (6) Å³
M_r = 233.69	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 11.6354 (4) Å	µ = 0.33 mm⁻¹
b = 6.3798 (2) Å	T = 150 K
c = 14.4513 (5) Å	0.40 × 0.30 × 0.30 mm
β = 92.767 (3)°

Data collection top

Agilent Xcalibur Ruby Gemini diffractometer	2274 independent reflections
Absorption correction: multi-scan CrysAlis PRO (Agilent, 2011)	1836 reflections with I > 2σ(I)
T_min = 0.879, T_max = 0.907	R_int = 0.026
4977 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.039	0 restraints
wR(F²) = 0.096	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	Δρ_max = 0.27 e Å⁻³
2274 reflections	Δρ_min = −0.26 e Å⁻³
149 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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

	x	y	z	U_iso*/U_eq
Cl2	0.59361 (4)	−0.24239 (8)	0.08648 (3)	0.0357 (2)
O6	0.57812 (10)	0.3697 (2)	0.60006 (8)	0.0280 (4)
N5	0.56976 (12)	0.2648 (3)	0.42004 (10)	0.0225 (5)
C1	0.63668 (14)	−0.1524 (3)	0.26774 (12)	0.0244 (5)
C2	0.58717 (14)	−0.0838 (3)	0.18511 (12)	0.0262 (5)
C3	0.53084 (14)	0.1108 (3)	0.17503 (12)	0.0275 (6)
C4	0.52189 (15)	0.2416 (3)	0.24985 (12)	0.0256 (5)
C4A	0.56937 (14)	0.1720 (3)	0.33521 (12)	0.0223 (5)
C5A	0.62720 (14)	0.1378 (3)	0.48468 (11)	0.0211 (5)
C6	0.63461 (14)	0.2152 (3)	0.58029 (12)	0.0229 (5)
C7	0.71201 (15)	0.1148 (3)	0.65476 (12)	0.0273 (5)
C8	0.80230 (15)	−0.0440 (3)	0.62766 (12)	0.0258 (5)
C9	0.75353 (15)	−0.2421 (3)	0.58213 (12)	0.0254 (5)
C10	0.73457 (16)	−0.2246 (3)	0.47726 (12)	0.0254 (5)
C10A	0.66477 (13)	−0.0419 (3)	0.44109 (12)	0.0214 (5)
C10B	0.62718 (14)	−0.0218 (3)	0.34549 (12)	0.0220 (5)
H1	0.67583	−0.28293	0.27228	0.0293*
H3	0.49882	0.15197	0.11609	0.0330*
H4	0.48492	0.37398	0.24388	0.0307*
H5	0.5389 (17)	0.380 (3)	0.4311 (14)	0.031 (6)*
H7A	0.66192	0.04481	0.69880	0.0328*
H7B	0.75270	0.22911	0.68916	0.0328*
H8A	0.85431	0.02420	0.58455	0.0309*
H8B	0.84908	−0.08411	0.68393	0.0309*
H9A	0.67922	−0.27558	0.60929	0.0305*
H9B	0.80688	−0.35980	0.59647	0.0305*
H10A	0.81089	−0.21821	0.44992	0.0305*
H10B	0.69653	−0.35477	0.45448	0.0305*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl2	0.0376 (3)	0.0460 (3)	0.0233 (2)	0.0078 (2)	0.0001 (2)	−0.0094 (2)
O6	0.0322 (7)	0.0244 (7)	0.0275 (7)	0.0012 (5)	0.0032 (5)	−0.0036 (6)
N5	0.0242 (8)	0.0205 (8)	0.0229 (8)	0.0027 (7)	0.0009 (6)	−0.0004 (7)
C1	0.0213 (8)	0.0259 (9)	0.0261 (9)	0.0005 (8)	0.0008 (7)	−0.0003 (8)
C2	0.0241 (9)	0.0336 (10)	0.0209 (9)	−0.0007 (8)	0.0026 (7)	−0.0058 (8)
C3	0.0219 (9)	0.0382 (11)	0.0222 (9)	0.0016 (8)	0.0002 (7)	0.0042 (8)
C4	0.0231 (8)	0.0269 (10)	0.0267 (9)	0.0039 (8)	0.0013 (7)	0.0035 (8)
C4A	0.0182 (8)	0.0245 (9)	0.0242 (9)	−0.0027 (7)	0.0016 (7)	−0.0005 (8)
C5A	0.0187 (8)	0.0209 (9)	0.0235 (8)	−0.0033 (7)	0.0003 (6)	0.0007 (7)
C6	0.0224 (8)	0.0220 (9)	0.0245 (9)	−0.0069 (7)	0.0031 (7)	−0.0008 (7)
C7	0.0322 (9)	0.0287 (10)	0.0208 (9)	−0.0034 (8)	−0.0011 (7)	0.0004 (8)
C8	0.0255 (9)	0.0280 (10)	0.0234 (9)	−0.0028 (8)	−0.0037 (7)	0.0025 (8)
C9	0.0259 (9)	0.0229 (9)	0.0269 (9)	0.0003 (7)	−0.0039 (8)	0.0035 (8)
C10	0.0272 (9)	0.0222 (9)	0.0265 (9)	0.0021 (7)	−0.0023 (7)	−0.0013 (8)
C10A	0.0175 (8)	0.0236 (9)	0.0230 (9)	−0.0036 (7)	0.0005 (6)	−0.0005 (7)
C10B	0.0177 (8)	0.0244 (9)	0.0238 (8)	−0.0024 (7)	0.0009 (7)	0.0002 (8)

Geometric parameters (Å, º) top

Cl2—C2	1.7525 (19)	C8—C9	1.522 (3)
O6—C6	1.226 (2)	C9—C10	1.525 (2)
N5—C4A	1.361 (2)	C10—C10A	1.500 (3)
N5—C5A	1.384 (2)	C10A—C10B	1.435 (2)
N5—H5	0.837 (19)	C1—H1	0.9500
C1—C10B	1.407 (3)	C3—H3	0.9500
C1—C2	1.372 (2)	C4—H4	0.9500
C2—C3	1.408 (3)	C7—H7A	0.9900
C3—C4	1.374 (3)	C7—H7B	0.9900
C4—C4A	1.399 (2)	C8—H8A	0.9900
C4A—C10B	1.412 (3)	C8—H8B	0.9900
C5A—C6	1.466 (2)	C9—H9A	0.9900
C5A—C10A	1.389 (3)	C9—H9B	0.9900
C6—C7	1.512 (2)	C10—H10A	0.9900
C7—C8	1.524 (3)	C10—H10B	0.9900

C4A—N5—C5A	109.50 (16)	C1—C10B—C10A	133.14 (17)
C4A—N5—H5	124.8 (14)	C2—C1—H1	121.00
C5A—N5—H5	125.7 (14)	C10B—C1—H1	121.00
C2—C1—C10B	117.39 (17)	C2—C3—H3	120.00
Cl2—C2—C3	117.57 (13)	C4—C3—H3	120.00
Cl2—C2—C1	119.41 (14)	C3—C4—H4	121.00
C1—C2—C3	123.02 (17)	C4A—C4—H4	121.00
C2—C3—C4	120.45 (16)	C6—C7—H7A	107.00
C3—C4—C4A	117.35 (17)	C6—C7—H7B	107.00
N5—C4A—C4	129.78 (18)	C8—C7—H7A	107.00
N5—C4A—C10B	107.77 (15)	C8—C7—H7B	107.00
C4—C4A—C10B	122.44 (17)	H7A—C7—H7B	107.00
N5—C5A—C6	116.33 (16)	C7—C8—H8A	109.00
C6—C5A—C10A	134.44 (16)	C7—C8—H8B	109.00
N5—C5A—C10A	109.23 (15)	C9—C8—H8A	109.00
O6—C6—C7	118.84 (16)	C9—C8—H8B	109.00
C5A—C6—C7	122.28 (16)	H8A—C8—H8B	108.00
O6—C6—C5A	118.86 (16)	C8—C9—H9A	109.00
C6—C7—C8	119.54 (15)	C8—C9—H9B	109.00
C7—C8—C9	114.57 (15)	C10—C9—H9A	109.00
C8—C9—C10	113.70 (15)	C10—C9—H9B	109.00
C9—C10—C10A	116.94 (15)	H9A—C9—H9B	108.00
C5A—C10A—C10B	105.96 (15)	C9—C10—H10A	108.00
C10—C10A—C10B	122.67 (16)	C9—C10—H10B	108.00
C5A—C10A—C10	131.32 (16)	C10A—C10—H10A	108.00
C4A—C10B—C10A	107.53 (16)	C10A—C10—H10B	108.00
C1—C10B—C4A	119.33 (16)	H10A—C10—H10B	107.00

C5A—N5—C4A—C4	−180.00 (18)	N5—C5A—C6—C7	−168.77 (16)
C5A—N5—C4A—C10B	0.65 (19)	C10A—C5A—C6—O6	−169.76 (18)
C4A—N5—C5A—C6	−179.61 (15)	C10A—C5A—C6—C7	12.0 (3)
C4A—N5—C5A—C10A	−0.2 (2)	N5—C5A—C10A—C10	177.14 (17)
C10B—C1—C2—Cl2	−178.65 (13)	N5—C5A—C10A—C10B	−0.37 (19)
C10B—C1—C2—C3	1.6 (3)	C6—C5A—C10A—C10	−3.6 (3)
C2—C1—C10B—C4A	−0.8 (2)	C6—C5A—C10A—C10B	178.93 (18)
C2—C1—C10B—C10A	178.53 (18)	O6—C6—C7—C8	−166.26 (16)
Cl2—C2—C3—C4	179.40 (14)	C5A—C6—C7—C8	12.0 (3)
C1—C2—C3—C4	−0.8 (3)	C6—C7—C8—C9	−63.1 (2)
C2—C3—C4—C4A	−0.8 (3)	C7—C8—C9—C10	88.01 (18)
C3—C4—C4A—N5	−177.70 (17)	C8—C9—C10—C10A	−52.9 (2)
C3—C4—C4A—C10B	1.6 (3)	C9—C10—C10A—C5A	11.6 (3)
N5—C4A—C10B—C1	178.59 (15)	C9—C10—C10A—C10B	−171.28 (16)
N5—C4A—C10B—C10A	−0.87 (19)	C5A—C10A—C10B—C1	−178.59 (18)
C4—C4A—C10B—C1	−0.8 (3)	C5A—C10A—C10B—C4A	0.75 (19)
C4—C4A—C10B—C10A	179.72 (16)	C10—C10A—C10B—C1	3.6 (3)
N5—C5A—C6—O6	9.5 (2)	C10—C10A—C10B—C4A	−177.02 (15)

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C1–C4,C4A,C10B ring.

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5···O6ⁱ	0.837 (19)	2.13 (2)	2.904 (2)	153.2 (19)
C9—H9A···O6ⁱⁱ	0.99	2.55	3.228 (2)	125
C7—H7A···Cg2ⁱⁱⁱ	0.99	2.95	3.7969 (19)	144

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, y−1, z; (iii) −x+1, −y, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₂ClNO
M_r	233.69
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	150
a, b, c (Å)	11.6354 (4), 6.3798 (2), 14.4513 (5)
β (°)	92.767 (3)
V (Å³)	1071.49 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.33
Crystal size (mm)	0.40 × 0.30 × 0.30

Data collection
Diffractometer	Agilent Xcalibur Ruby Gemini diffractometer
Absorption correction	Multi-scan CrysAlis PRO (Agilent, 2011)
T_min, T_max	0.879, 0.907
No. of measured, independent and observed [I > 2σ(I)] reflections	4977, 2274, 1836
R_int	0.026
(sin θ/λ)_max (Å⁻¹)	0.670

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.039, 0.096, 1.04
No. of reflections	2274
No. of parameters	149
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.26

Computer programs: CrysAlis PRO (Agilent, 2011), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

Cg2 is the centroid of the C1–C4,C4A,C10B ring.

D—H···A	D—H	H···A	D···A	D—H···A
N5—H5···O6ⁱ	0.837 (19)	2.13 (2)	2.904 (2)	153.2 (19)
C9—H9A···O6ⁱⁱ	0.99	2.55	3.228 (2)	125
C7—H7A···Cg2ⁱⁱⁱ	0.99	2.95	3.7969 (19)	144

Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x, y−1, z; (iii) −x+1, −y, −z+1.

Acknowledgements

RJB acknowledges the NSF MRI program (grant No. CHE-0619278) for funds to purchase an X-ray diffractometer.

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