Ethyl 1-phenyl­sulfonyl-1H-indole-2-carboxyl­ate

Ramathilagam, C.; Saravanan, V.; Mohanakrishnan, A.K.; Umarani, P.R.; Manivannan, V.

doi:10.1107/S1600536811035392

organic compounds

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ISSN: 2056-9890

Volume 67| Part 10| October 2011| Page o2549

https://doi.org/10.1107/S1600536811035392

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Ethyl 1-phenylsulfonyl-1H-indole-2-carboxylate

C. Ramathilagam,^a V. Saravanan,^b A. K. Mohanakrishnan,^b P. R. Umarani ^c and V. Manivannan ^d ^*

^aDepartment of Physics, AMET University, Kanathur, Chennai 603 112, India, ^bDepartment of Organic Chemistry, University of Madras, Guindy Campus, Chennai 600 025, India, ^cDepartment of Physics, Presidency College (Autonomous), Chennai 600 005, India, and ^dDepartment of Research and Development, PRIST University, Vallam, Thanjavur 613 403, Tamil Nadu, India
^*Correspondence e-mail: crystallography2010@gmail.com

(Received 19 August 2011; accepted 30 August 2011; online 3 September 2011)

In the title compound, C₁₇H₁₅NO₄S, the six-membered ring of the indole unit makes a dihedral angle of 72.40 (5)° with the phenyl ring. The molecular structure features a short C—H⋯O contact.

Related literature

For the biological activity of Indole derivatives, see: Joshi & Chand (1982 ); Pomarnacka & Kozlarska-Kedra (2003 ); For a related structure, see: Chakkaravarthi et al. (2010 ).

Experimental

Crystal data

C₁₇H₁₅NO₄S
M_r = 329.36
Monoclinic, P 2₁ /n
a = 10.6936 (6) Å
b = 7.5331 (4) Å
c = 19.5654 (12) Å
β = 96.647 (2)°
V = 1565.52 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.23 mm⁻¹
T = 295 K
0.22 × 0.20 × 0.18 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.952, T_max = 0.960
35524 measured reflections
4353 independent reflections
3245 reflections with I > 2σ(I)
R_int = 0.041

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.129
S = 1.02
4353 reflections
209 parameters
H-atom parameters constrained
Δρ_max = 0.33 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1	0.93	2.29	2.839 (2)	117

Data collection: APEX2 (Bruker, 2004 ); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97 .

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536811035392/bt5624sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811035392/bt5624Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536811035392/bt5624Isup3.cml

checkCIF report

Comment top

Compounds containing the indole moiety exhibit antibacterial and fungicidal activities (Joshi & Chand, 1982). In addition, indole derivatives are also known to exhibit anticancer and anti-HIV (Pomarnacka & Kozlarska-Kedra, 2003) activities.

The geometric parameters of the title molecule (Fig. 1) agree well with reported similar structures (Chakkaravarthi et al., 2010) The dihedral angle between the six membered ring of the indole moiety and the benzene ring is 72.40 (5)°. The sum of bond angles around N1 [359.03 (9) °] indicates the sp² hybridization state. The molecular structure is stabilized by weak intramolecular C—H···O interaction.

Related literature top

For the biological activity of Indole derivatives, see: Joshi & Chand (1982); Pomarnacka & Kozlarska-Kedra (2003); For a related structure, see: Chakkaravarthi et al. (2010)

Experimental top

Ethyl-indole-2- carboxylate (1 g,5.29 mmol) was dissolved in distilled benzene (20 ml). To this benzenesulfonyl chloride (0.82 ml,5.82 mmol) and 60% NaOH (2.1 g in3.52 ml) were added along with tetra butyl ammonium hydrogen sulfate (1.0 g). This two phase system was stirred at room temperature for 2 h. It was then diluted with water (50 ml)and the organic layer was separated. The aqueous layer was extracted with benzene (2x20 ml)and the combined organic extracts were dried(Na₂SO₄). The solvent was removed completely and the crude product was recrystallized from methanol afforded ethyl- 1-phenylsulfonyl-indole 2-carboxylate (m.p 395–397 K).

Structure description top

For the biological activity of Indole derivatives, see: Joshi & Chand (1982); Pomarnacka & Kozlarska-Kedra (2003); For a related structure, see: Chakkaravarthi et al. (2010)

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (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: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms.

Ethyl 1-phenylsulfonyl-1H-indole-2-carboxylate top

Crystal data top

C₁₇H₁₅NO₄S	F(000) = 688
M_r = 329.36	D_x = 1.397 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2Yn	Cell parameters from 4353 reflections
a = 10.6936 (6) Å	θ = 2.1–29.5°
b = 7.5331 (4) Å	µ = 0.23 mm⁻¹
c = 19.5654 (12) Å	T = 295 K
β = 96.647 (2)°	Block, colourless
V = 1565.52 (15) Å³	0.22 × 0.20 × 0.18 mm
Z = 4

Data collection top

Bruker Kappa APEXII CCD diffractometer	4353 independent reflections
Radiation source: fine-focus sealed tube	3245 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.041
Detector resolution: 0 pixels mm^-1	θ_max = 29.5°, θ_min = 2.1°
ω and φ scans	h = −14→14
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −10→10
T_min = 0.952, T_max = 0.960	l = −26→27
35524 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)] = 0.042	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.129	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0661P)² + 0.3737P] where P = (F_o² + 2F_c²)/3
4353 reflections	(Δ/σ)_max = 0.001
209 parameters	Δρ_max = 0.33 e Å⁻³
0 restraints	Δρ_min = −0.23 e Å⁻³

Crystal data top

C₁₇H₁₅NO₄S	V = 1565.52 (15) Å³
M_r = 329.36	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.6936 (6) Å	µ = 0.23 mm⁻¹
b = 7.5331 (4) Å	T = 295 K
c = 19.5654 (12) Å	0.22 × 0.20 × 0.18 mm
β = 96.647 (2)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	4353 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3245 reflections with I > 2σ(I)
T_min = 0.952, T_max = 0.960	R_int = 0.041
35524 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.129	H-atom parameters constrained
S = 1.02	Δρ_max = 0.33 e Å⁻³
4353 reflections	Δρ_min = −0.23 e Å⁻³
209 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
C1	0.75477 (14)	0.1614 (2)	0.14296 (8)	0.0459 (3)
C2	0.76555 (18)	0.1553 (3)	0.07299 (10)	0.0595 (4)
H2	0.6951	0.1613	0.0404	0.071*
C3	0.8851 (2)	0.1399 (3)	0.05402 (12)	0.0707 (5)
H3	0.8950	0.1358	0.0075	0.085*
C4	0.99095 (19)	0.1305 (3)	0.10177 (13)	0.0746 (6)
H4	1.0700	0.1195	0.0868	0.090*
C5	0.98078 (17)	0.1371 (3)	0.16998 (12)	0.0667 (5)
H5	1.0523	0.1320	0.2019	0.080*
C6	0.86132 (15)	0.1518 (2)	0.19186 (9)	0.0500 (4)
C7	0.82011 (15)	0.1562 (2)	0.25786 (9)	0.0517 (4)
H7	0.8717	0.1525	0.2995	0.062*
C8	0.69340 (14)	0.1666 (2)	0.25026 (8)	0.0444 (3)
C9	0.61219 (15)	0.1458 (2)	0.30554 (9)	0.0479 (4)
C10	0.6183 (2)	0.1412 (3)	0.42624 (10)	0.0699 (5)
H10A	0.5795	0.0247	0.4225	0.084*
H10B	0.5535	0.2287	0.4314	0.084*
C11	0.7173 (3)	0.1476 (4)	0.48626 (12)	0.0924 (8)
H11A	0.7850	0.0694	0.4783	0.139*
H11B	0.6821	0.1109	0.5269	0.139*
H11C	0.7487	0.2667	0.4922	0.139*
C12	0.42232 (13)	0.0165 (2)	0.14176 (8)	0.0443 (3)
C13	0.31930 (15)	−0.0030 (3)	0.17714 (10)	0.0562 (4)
H13	0.2935	0.0894	0.2038	0.067*
C14	0.25463 (18)	−0.1627 (3)	0.17237 (11)	0.0653 (5)
H14	0.1838	−0.1774	0.1952	0.078*
C15	0.2945 (2)	−0.2984 (3)	0.13425 (11)	0.0682 (5)
H15	0.2515	−0.4060	0.1320	0.082*
C16	0.3978 (2)	−0.2779 (3)	0.09909 (11)	0.0661 (5)
H16	0.4242	−0.3715	0.0733	0.079*
C17	0.46224 (17)	−0.1190 (2)	0.10196 (9)	0.0558 (4)
H17	0.5311	−0.1034	0.0776	0.067*
N1	0.64889 (11)	0.17160 (18)	0.17945 (7)	0.0445 (3)
O1	0.51424 (12)	0.27385 (18)	0.07617 (7)	0.0626 (3)
O2	0.44931 (11)	0.33875 (16)	0.18971 (7)	0.0589 (3)
O3	0.50501 (12)	0.09756 (19)	0.29867 (7)	0.0646 (3)
O4	0.67930 (12)	0.17905 (19)	0.36602 (6)	0.0611 (3)
S1	0.50234 (3)	0.22047 (5)	0.14475 (2)	0.04621 (13)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0410 (8)	0.0423 (7)	0.0540 (9)	0.0003 (6)	0.0037 (6)	0.0018 (6)
C2	0.0572 (10)	0.0664 (11)	0.0551 (10)	−0.0002 (8)	0.0071 (8)	0.0046 (8)
C3	0.0731 (13)	0.0750 (13)	0.0678 (12)	0.0045 (10)	0.0247 (10)	0.0025 (10)
C4	0.0519 (11)	0.0801 (14)	0.0961 (17)	0.0050 (10)	0.0263 (11)	0.0025 (12)
C5	0.0409 (9)	0.0747 (13)	0.0846 (14)	0.0047 (8)	0.0071 (9)	−0.0044 (10)
C6	0.0391 (7)	0.0463 (8)	0.0633 (10)	0.0011 (6)	0.0004 (7)	−0.0017 (7)
C7	0.0412 (8)	0.0554 (9)	0.0554 (9)	0.0053 (7)	−0.0068 (7)	−0.0053 (7)
C8	0.0407 (7)	0.0433 (7)	0.0472 (8)	0.0035 (6)	−0.0035 (6)	−0.0010 (6)
C9	0.0459 (8)	0.0452 (8)	0.0510 (9)	0.0076 (6)	−0.0011 (7)	0.0006 (6)
C10	0.0802 (14)	0.0781 (13)	0.0521 (11)	0.0125 (11)	0.0106 (9)	0.0039 (9)
C11	0.116 (2)	0.1060 (19)	0.0524 (12)	0.0233 (16)	−0.0021 (12)	0.0063 (12)
C12	0.0362 (7)	0.0461 (7)	0.0474 (8)	0.0036 (6)	−0.0083 (6)	0.0005 (6)
C13	0.0407 (8)	0.0596 (10)	0.0672 (11)	0.0006 (7)	0.0012 (7)	−0.0057 (8)
C14	0.0487 (10)	0.0690 (11)	0.0761 (13)	−0.0103 (8)	−0.0017 (9)	0.0078 (10)
C15	0.0701 (12)	0.0534 (10)	0.0747 (13)	−0.0123 (9)	−0.0188 (10)	0.0068 (9)
C16	0.0773 (13)	0.0498 (9)	0.0666 (12)	0.0052 (9)	−0.0111 (10)	−0.0081 (8)
C17	0.0544 (9)	0.0557 (9)	0.0551 (10)	0.0061 (7)	−0.0027 (7)	−0.0051 (7)
N1	0.0352 (6)	0.0516 (7)	0.0452 (7)	0.0011 (5)	−0.0015 (5)	0.0022 (5)
O1	0.0546 (7)	0.0708 (8)	0.0595 (8)	0.0042 (6)	−0.0051 (6)	0.0204 (6)
O2	0.0503 (7)	0.0461 (6)	0.0784 (9)	0.0119 (5)	−0.0001 (6)	−0.0040 (6)
O3	0.0481 (7)	0.0822 (9)	0.0629 (8)	−0.0033 (6)	0.0042 (6)	0.0031 (7)
O4	0.0590 (7)	0.0773 (8)	0.0458 (7)	0.0003 (6)	0.0003 (5)	−0.0031 (6)
S1	0.0382 (2)	0.0439 (2)	0.0542 (2)	0.00539 (14)	−0.00468 (15)	0.00506 (16)

Geometric parameters (Å, º) top

C1—C2	1.388 (2)	C10—H10A	0.9700
C1—C6	1.402 (2)	C10—H10B	0.9700
C1—N1	1.409 (2)	C11—H11A	0.9600
C2—C3	1.376 (3)	C11—H11B	0.9600
C2—H2	0.9300	C11—H11C	0.9600
C3—C4	1.384 (3)	C12—C13	1.375 (2)
C3—H3	0.9300	C12—C17	1.381 (2)
C4—C5	1.352 (3)	C12—S1	1.7567 (16)
C4—H4	0.9300	C13—C14	1.386 (3)
C5—C6	1.398 (2)	C13—H13	0.9300
C5—H5	0.9300	C14—C15	1.363 (3)
C6—C7	1.412 (3)	C14—H14	0.9300
C7—C8	1.348 (2)	C15—C16	1.376 (3)
C7—H7	0.9300	C15—H15	0.9300
C8—N1	1.412 (2)	C16—C17	1.379 (3)
C8—C9	1.472 (2)	C16—H16	0.9300
C9—O3	1.195 (2)	C17—H17	0.9300
C9—O4	1.335 (2)	N1—S1	1.6752 (13)
C10—O4	1.440 (2)	O1—S1	1.4204 (13)
C10—C11	1.488 (3)	O2—S1	1.4159 (13)

C2—C1—C6	121.18 (16)	C10—C11—H11B	109.5
C2—C1—N1	131.69 (15)	H11A—C11—H11B	109.5
C6—C1—N1	107.11 (14)	C10—C11—H11C	109.5
C3—C2—C1	117.02 (18)	H11A—C11—H11C	109.5
C3—C2—H2	121.5	H11B—C11—H11C	109.5
C1—C2—H2	121.5	C13—C12—C17	121.55 (16)
C2—C3—C4	122.4 (2)	C13—C12—S1	119.47 (13)
C2—C3—H3	118.8	C17—C12—S1	118.95 (13)
C4—C3—H3	118.8	C12—C13—C14	118.77 (18)
C5—C4—C3	120.76 (18)	C12—C13—H13	120.6
C5—C4—H4	119.6	C14—C13—H13	120.6
C3—C4—H4	119.6	C15—C14—C13	120.20 (19)
C4—C5—C6	119.07 (19)	C15—C14—H14	119.9
C4—C5—H5	120.5	C13—C14—H14	119.9
C6—C5—H5	120.5	C14—C15—C16	120.64 (18)
C5—C6—C1	119.62 (18)	C14—C15—H15	119.7
C5—C6—C7	132.45 (17)	C16—C15—H15	119.7
C1—C6—C7	107.92 (14)	C15—C16—C17	120.23 (18)
C8—C7—C6	108.45 (15)	C15—C16—H16	119.9
C8—C7—H7	125.8	C17—C16—H16	119.9
C6—C7—H7	125.8	C16—C17—C12	118.60 (18)
C7—C8—N1	109.27 (14)	C16—C17—H17	120.7
C7—C8—C9	125.71 (15)	C12—C17—H17	120.7
N1—C8—C9	124.28 (13)	C1—N1—C8	107.24 (12)
O3—C9—O4	124.55 (16)	C1—N1—S1	125.14 (11)
O3—C9—C8	126.12 (16)	C8—N1—S1	126.64 (11)
O4—C9—C8	109.22 (14)	C9—O4—C10	116.12 (15)
O4—C10—C11	106.90 (19)	O2—S1—O1	119.66 (8)
O4—C10—H10A	110.3	O2—S1—N1	108.04 (7)
C11—C10—H10A	110.3	O1—S1—N1	105.26 (7)
O4—C10—H10B	110.3	O2—S1—C12	110.04 (8)
C11—C10—H10B	110.3	O1—S1—C12	108.23 (8)
H10A—C10—H10B	108.6	N1—S1—C12	104.50 (7)
C10—C11—H11A	109.5

C6—C1—C2—C3	−0.2 (3)	C13—C12—C17—C16	−1.2 (2)
N1—C1—C2—C3	−178.06 (18)	S1—C12—C17—C16	−179.06 (14)
C1—C2—C3—C4	0.1 (3)	C2—C1—N1—C8	177.65 (17)
C2—C3—C4—C5	−0.4 (3)	C6—C1—N1—C8	−0.45 (17)
C3—C4—C5—C6	0.7 (3)	C2—C1—N1—S1	−13.1 (3)
C4—C5—C6—C1	−0.7 (3)	C6—C1—N1—S1	168.80 (11)
C4—C5—C6—C7	177.8 (2)	C7—C8—N1—C1	0.77 (18)
C2—C1—C6—C5	0.5 (3)	C9—C8—N1—C1	−169.90 (14)
N1—C1—C6—C5	178.83 (16)	C7—C8—N1—S1	−168.27 (12)
C2—C1—C6—C7	−178.36 (16)	C9—C8—N1—S1	21.1 (2)
N1—C1—C6—C7	−0.01 (18)	O3—C9—O4—C10	4.4 (2)
C5—C6—C7—C8	−178.14 (19)	C8—C9—O4—C10	−171.90 (15)
C1—C6—C7—C8	0.49 (19)	C11—C10—O4—C9	167.30 (18)
C6—C7—C8—N1	−0.78 (19)	C1—N1—S1—O2	−137.60 (13)
C6—C7—C8—C9	169.72 (15)	C8—N1—S1—O2	29.58 (15)
C7—C8—C9—O3	−153.97 (18)	C1—N1—S1—O1	−8.67 (15)
N1—C8—C9—O3	15.2 (3)	C8—N1—S1—O1	158.50 (13)
C7—C8—C9—O4	22.3 (2)	C1—N1—S1—C12	105.25 (14)
N1—C8—C9—O4	−168.58 (14)	C8—N1—S1—C12	−87.58 (14)
C17—C12—C13—C14	0.0 (2)	C13—C12—S1—O2	3.79 (15)
S1—C12—C13—C14	177.82 (13)	C17—C12—S1—O2	−178.30 (12)
C12—C13—C14—C15	1.2 (3)	C13—C12—S1—O1	−128.64 (13)
C13—C14—C15—C16	−1.2 (3)	C17—C12—S1—O1	49.27 (14)
C14—C15—C16—C17	−0.1 (3)	C13—C12—S1—N1	119.56 (13)
C15—C16—C17—C12	1.3 (3)	C17—C12—S1—N1	−62.53 (14)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1	0.93	2.29	2.839 (2)	117
C13—H13···O2	0.93	2.55	2.923 (2)	105

Experimental details

Crystal data
Chemical formula	C₁₇H₁₅NO₄S
M_r	329.36
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	295
a, b, c (Å)	10.6936 (6), 7.5331 (4), 19.5654 (12)
β (°)	96.647 (2)
V (Å³)	1565.52 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.23
Crystal size (mm)	0.22 × 0.20 × 0.18

Data collection
Diffractometer	Bruker Kappa APEXII CCD
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.952, 0.960
No. of measured, independent and observed [I > 2σ(I)] reflections	35524, 4353, 3245
R_int	0.041
(sin θ/λ)_max (Å⁻¹)	0.693

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.129, 1.02
No. of reflections	4353
No. of parameters	209
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.33, −0.23

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···O1	0.93	2.29	2.839 (2)	116.9
C13—H13···O2	0.93	2.55	2.923 (2)	104.5

Acknowledgements

CR wishes to acknowledge AMET University management, India, for their kind support.

References

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