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

Abstract

In the title mol­ecule, C₁₄H₁₅NO, the dihedral angle between the benzene and pyrrole rings is 1.99 (12)°. The cyclo­heptene ring adopts a slightly distorted boat conformation.

Related literature

For the inter­est and importance of indole derivatives, see: Csomós et al. (2007 ▶). For pyrido-fused cyclo­hept[b]indole alkaloids, see: Bennasar et al. (1997 ▶). For crystallographic studies of cyclo­hept[b]indoles, see: Archana et al. (2010 ▶).

Experimental

Crystal data

• C₁₄H₁₅NO

• M _r = 213.27

• Orthorhombic,

• a = 8.6999 (2) Å

• b = 14.1805 (3) Å

• c = 9.1392 (3) Å

• V = 1127.49 (5) ų

• Z = 4

• Cu Kα radiation

• μ = 0.62 mm⁻¹

• T = 295 K

• 0.47 × 0.35 × 0.20 mm

Data collection

• Oxford Diffraction Xcalibur Ruby Gemini diffractometer

• Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010 ▶) T _min = 0.803, T _max = 1.000

• 1184 measured reflections

• 1184 independent reflections

• 1148 reflections with I > 2σ(I)

• R _int = 0.020

Refinement

• R[F ² > 2σ(F ²)] = 0.037

• wR(F ²) = 0.106

• S = 1.07

• 1184 reflections

• 147 parameters

• 1 restraint

• H-atom parameters constrained

• Δρ_max = 0.14 e Å⁻³

• Δρ_min = −0.13 e Å⁻³

Data collection: CrysAlis PRO (Oxford Diffraction, 2010 ▶); 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 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811016229/hg5032Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Indole derivatives condensed with different heterocycles are physiologically active compounds found in abundance in materials such as pharmaceuticals, alkaloids and potential therapeutic agents (Csomós et al., 2007). Ervitsine and Ervatamine (Bennasar et al., 1997) were important class of pyrido fused cyclohept[b]indole alkaloids. Recently we have reported crystallographic studies for some cyclohept[b]indoles in our laboratory (Archana et al., 2010).

The molecular structure of the title compound, with atomic numbering scheme, is shown in Fig. 1. In the title molecule, C₁₄H₁₅NO, the dihedral angle between the benzene and pyrrole rings is 1.99 (12)°. The cycloheptene ring adopts a slightly distorted boat conformation.

Experimental

To a solution of 7,8,9,10-tetrahydrocyclohepta[b]indol-6(5H)-one (0.199 g, 0.001 mol) in 5 ml acetone added powdered KOH (0.280 g, 0.005 mol) in ice cold condition. After few minutes methyl iodide (0.13 ml, 0.002 mol) was added drop by drop with vigorous stirring and the reaction mixture was stirrired for 15 min at room temperature. Benzene was added to the reaction mixture and insoluble materials are removed by filtration. The benzene solution was washed with saturated NaCl solution, dried by using Na₂SO₄ and evaporation yielded the title compound (0.191 g, 90%). This was recrystallized from benzene and ethyl acetate mixture.

Refinement

Owing to the absence of any anamalous scatterers in the molecule, the Friedel pairs were merged. The absolute structure in the present model have been chosen arbitrarily. H atoms were positioned geometrically and allowed to ride on their parent atoms, with C—H = 0.93 - 0.97 Å and U_iso(H) = 1.2 - 1.5 times U_eq(C).

Figures

Fig. 1.

The molecular structure of the title compound, showing the atom-numbering scheme and displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.

Crystal data

C14H15NO	Dx = 1.256 Mg m−3
Mr = 213.27	Melting point: 338 K
Orthorhombic, Pca21	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2c -2ac	Cell parameters from 2006 reflections
a = 8.6999 (2) Å	θ = 4.8–73.4°
b = 14.1805 (3) Å	µ = 0.62 mm−1
c = 9.1392 (3) Å	T = 295 K
V = 1127.49 (5) Å3	Chunk, pale-yellow
Z = 4	0.47 × 0.35 × 0.20 mm
F(000) = 456

Data collection

Oxford Diffraction Xcalibur Ruby Gemini diffractometer	1184 independent reflections
Radiation source: Enhance (Cu) X-ray Source	1148 reflections with I > 2σ(I)
graphite	Rint = 0.020
Detector resolution: 10.5081 pixels mm-1	θmax = 73.6°, θmin = 6.0°
ω scans	h = 0→10
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2010)	k = 0→17
Tmin = 0.803, Tmax = 1.000	l = 0→11
1184 measured reflections

Refinement

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.037	w = 1/[σ2(Fo2) + (0.0678P)2 + 0.0651P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.106	(Δ/σ)max = 0.001
S = 1.07	Δρmax = 0.14 e Å−3
1184 reflections	Δρmin = −0.13 e Å−3
147 parameters	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
1 restraint	Extinction coefficient: 0.018 (2)
Primary atom site location: structure-invariant direct methods	Absolute structure: see Refinement section in Supplementary materials
Secondary atom site location: difference Fourier map

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O6	0.5677 (3)	0.05292 (17)	0.4636 (4)	0.1141 (10)
N5	0.4250 (2)	0.18603 (13)	0.6610 (2)	0.0514 (5)
C1	0.4932 (3)	0.42768 (16)	0.7515 (3)	0.0607 (8)
C2	0.3719 (3)	0.4495 (2)	0.8403 (4)	0.0792 (10)
C3	0.2600 (4)	0.3822 (2)	0.8755 (4)	0.0826 (10)
C4	0.2661 (3)	0.2923 (2)	0.8220 (3)	0.0686 (9)
C4A	0.3895 (2)	0.26879 (16)	0.7301 (2)	0.0512 (7)
C5	0.3392 (3)	0.09825 (18)	0.6805 (4)	0.0791 (10)
C5A	0.5637 (3)	0.19791 (14)	0.5882 (2)	0.0471 (6)
C6	0.6360 (4)	0.12408 (16)	0.4995 (3)	0.0637 (9)
C7	0.7989 (3)	0.13870 (18)	0.4529 (3)	0.0669 (9)
C8	0.9072 (3)	0.1731 (2)	0.5724 (3)	0.0713 (9)
C9	0.9058 (3)	0.2786 (2)	0.6046 (3)	0.0647 (8)
C10	0.7621 (3)	0.33087 (14)	0.5528 (3)	0.0533 (6)
C10A	0.6154 (2)	0.28910 (14)	0.6081 (2)	0.0431 (5)
C10B	0.5048 (2)	0.33542 (14)	0.6960 (2)	0.0458 (6)
H1	0.56661	0.47293	0.72821	0.0728*
H2	0.36341	0.51021	0.87808	0.0950*
H3	0.17945	0.39907	0.93704	0.0989*
H4	0.19098	0.24819	0.84567	0.0823*
H5A	0.25845	0.10790	0.75052	0.1184*
H5B	0.29541	0.07936	0.58858	0.1184*
H5C	0.40722	0.04986	0.71507	0.1184*
H7A	0.83814	0.07958	0.41476	0.0803*
H7B	0.80020	0.18409	0.37351	0.0803*
H8A	0.88223	0.13988	0.66208	0.0856*
H8B	1.01113	0.15535	0.54543	0.0856*
H9A	0.91596	0.28753	0.70940	0.0776*
H9B	0.99487	0.30708	0.55857	0.0776*
H10A	0.76018	0.33072	0.44669	0.0640*
H10B	0.76828	0.39599	0.58476	0.0640*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
O6	0.131 (2)	0.0782 (13)	0.133 (2)	−0.0248 (14)	0.030 (2)	−0.0505 (16)
N5	0.0472 (9)	0.0535 (9)	0.0534 (10)	−0.0053 (7)	−0.0045 (8)	0.0057 (8)
C1	0.0620 (13)	0.0556 (12)	0.0644 (14)	0.0153 (10)	−0.0049 (12)	−0.0035 (11)
C2	0.0837 (19)	0.0764 (16)	0.0774 (18)	0.0354 (15)	0.0030 (16)	−0.0123 (16)
C3	0.0671 (15)	0.111 (2)	0.0696 (17)	0.0405 (18)	0.0133 (15)	0.0049 (17)
C4	0.0442 (12)	0.0964 (17)	0.0652 (15)	0.0115 (12)	0.0043 (11)	0.0162 (15)
C4A	0.0408 (10)	0.0643 (12)	0.0486 (12)	0.0048 (9)	−0.0069 (9)	0.0089 (10)
C5	0.0732 (17)	0.0691 (14)	0.095 (2)	−0.0234 (13)	−0.0062 (17)	0.0152 (16)
C5A	0.0508 (11)	0.0484 (10)	0.0421 (10)	0.0017 (8)	−0.0035 (9)	0.0048 (9)
C6	0.0855 (18)	0.0514 (12)	0.0541 (14)	0.0054 (11)	−0.0011 (13)	−0.0046 (10)
C7	0.0838 (18)	0.0654 (13)	0.0514 (13)	0.0252 (12)	0.0133 (13)	0.0021 (11)
C8	0.0639 (14)	0.0833 (17)	0.0668 (16)	0.0278 (13)	0.0048 (13)	0.0131 (15)
C9	0.0421 (11)	0.0857 (16)	0.0663 (15)	0.0022 (11)	0.0033 (11)	0.0069 (14)
C10	0.0538 (11)	0.0519 (9)	0.0542 (13)	−0.0005 (9)	0.0045 (10)	0.0087 (9)
C10A	0.0436 (10)	0.0438 (8)	0.0418 (10)	0.0050 (7)	−0.0036 (8)	0.0043 (8)
C10B	0.0421 (10)	0.0506 (10)	0.0448 (11)	0.0083 (7)	−0.0055 (8)	0.0029 (8)

Geometric parameters (Å, °)

O6—C6	1.216 (4)	C10A—C10B	1.415 (3)
N5—C4A	1.368 (3)	C1—H1	0.9300
N5—C5	1.462 (3)	C2—H2	0.9300
N5—C5A	1.388 (3)	C3—H3	0.9300
C1—C2	1.367 (4)	C4—H4	0.9300
C1—C10B	1.407 (3)	C5—H5A	0.9600
C2—C3	1.401 (4)	C5—H5B	0.9600
C3—C4	1.366 (4)	C5—H5C	0.9600
C4—C4A	1.403 (3)	C7—H7A	0.9700
C4A—C10B	1.413 (3)	C7—H7B	0.9700
C5A—C6	1.466 (3)	C8—H8A	0.9700
C5A—C10A	1.381 (3)	C8—H8B	0.9700
C6—C7	1.494 (4)	C9—H9A	0.9700
C7—C8	1.523 (4)	C9—H9B	0.9700
C8—C9	1.525 (4)	C10—H10A	0.9700
C9—C10	1.529 (4)	C10—H10B	0.9700
C10—C10A	1.495 (3)
C4A—N5—C5	123.97 (19)	C2—C3—H3	119.00
C4A—N5—C5A	108.26 (17)	C4—C3—H3	119.00
C5—N5—C5A	127.26 (19)	C3—C4—H4	121.00
C2—C1—C10B	118.7 (2)	C4A—C4—H4	121.00
C1—C2—C3	121.3 (3)	N5—C5—H5A	109.00
C2—C3—C4	121.8 (3)	N5—C5—H5B	109.00
C3—C4—C4A	117.8 (3)	N5—C5—H5C	110.00
N5—C4A—C4	130.8 (2)	H5A—C5—H5B	109.00
N5—C4A—C10B	108.16 (16)	H5A—C5—H5C	109.00
C4—C4A—C10B	121.1 (2)	H5B—C5—H5C	109.00
N5—C5A—C6	123.5 (2)	C6—C7—H7A	108.00
N5—C5A—C10A	109.49 (18)	C6—C7—H7B	108.00
C6—C5A—C10A	127.0 (2)	C8—C7—H7A	108.00
O6—C6—C5A	122.2 (3)	C8—C7—H7B	108.00
O6—C6—C7	120.1 (3)	H7A—C7—H7B	107.00
C5A—C6—C7	117.7 (2)	C7—C8—H8A	108.00
C6—C7—C8	115.3 (2)	C7—C8—H8B	108.00
C7—C8—C9	116.6 (2)	C9—C8—H8A	108.00
C8—C9—C10	115.0 (2)	C9—C8—H8B	108.00
C9—C10—C10A	113.67 (19)	H8A—C8—H8B	107.00
C5A—C10A—C10	127.19 (19)	C8—C9—H9A	109.00
C5A—C10A—C10B	106.73 (17)	C8—C9—H9B	109.00
C10—C10A—C10B	126.05 (18)	C10—C9—H9A	108.00
C1—C10B—C4A	119.44 (18)	C10—C9—H9B	108.00
C1—C10B—C10A	133.24 (19)	H9A—C9—H9B	108.00
C4A—C10B—C10A	107.31 (17)	C9—C10—H10A	109.00
C2—C1—H1	121.00	C9—C10—H10B	109.00
C10B—C1—H1	121.00	C10A—C10—H10A	109.00
C1—C2—H2	119.00	C10A—C10—H10B	109.00
C3—C2—H2	119.00	H10A—C10—H10B	108.00
C5—N5—C4A—C4	−4.8 (4)	N5—C5A—C6—O6	12.5 (4)
C5—N5—C4A—C10B	174.5 (2)	N5—C5A—C6—C7	−167.6 (2)
C5A—N5—C4A—C4	−177.2 (2)	C10A—C5A—C6—O6	−164.4 (3)
C5A—N5—C4A—C10B	2.2 (2)	C10A—C5A—C6—C7	15.4 (4)
C4A—N5—C5A—C6	−178.7 (2)	N5—C5A—C10A—C10	177.9 (2)
C4A—N5—C5A—C10A	−1.3 (2)	N5—C5A—C10A—C10B	−0.1 (2)
C5—N5—C5A—C6	9.3 (4)	C6—C5A—C10A—C10	−4.8 (4)
C5—N5—C5A—C10A	−173.3 (2)	C6—C5A—C10A—C10B	177.2 (2)
C10B—C1—C2—C3	−0.4 (5)	O6—C6—C7—C8	−134.4 (3)
C2—C1—C10B—C4A	1.6 (3)	C5A—C6—C7—C8	45.7 (3)
C2—C1—C10B—C10A	−177.2 (2)	C6—C7—C8—C9	−81.6 (3)
C1—C2—C3—C4	−0.6 (5)	C7—C8—C9—C10	19.9 (3)
C2—C3—C4—C4A	0.3 (5)	C8—C9—C10—C10A	54.1 (3)
C3—C4—C4A—N5	−179.7 (3)	C9—C10—C10A—C5A	−57.7 (3)
C3—C4—C4A—C10B	1.0 (4)	C9—C10—C10A—C10B	119.9 (2)
N5—C4A—C10B—C1	178.60 (19)	C5A—C10A—C10B—C1	−179.6 (2)
N5—C4A—C10B—C10A	−2.3 (2)	C5A—C10A—C10B—C4A	1.5 (2)
C4—C4A—C10B—C1	−2.0 (3)	C10—C10A—C10B—C1	2.4 (4)
C4—C4A—C10B—C10A	177.16 (19)	C10—C10A—C10B—C4A	−176.58 (19)