2-[5-Bromo-1-(3-chloro­benz­yl)-2-methyl-1H-indol-3-yl]acetic acid

Elkady, M.; Keck, P.R.W.E.F.; Schollmeyer, D.; Laufer, S.

doi:10.1107/S1600536812046740

organic compounds

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ISSN: 2056-9890

Volume 68| Part 12| December 2012| Page o3396

doi:10.1107/S1600536812046740

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2-[5-Bromo-1-(3-chlorobenzyl)-2-methyl-1H-indol-3-yl]acetic acid

Mahmoud Elkady,^a Peter R. W. E. F. Keck,^a Dieter Schollmeyer ^b and Stefan Laufer ^a ^*

^aEberhard-Karls-University Tübingen, Auf der Morgenstelle 8, 72076 Tübingen, Germany, and ^bUniversity Mainz, Institut of Organic Chemistry, Duesbergweg 10-14, 55099 Mainz, Germany
^*Correspondence e-mail: stefan.laufer@uni-tuebingen.de

(Received 12 November 2012; accepted 13 November 2012; online 24 November 2012)

In the title compound, C₁₈H₁₅BrClNO₂, the indole ring system forms a dihedral angle of 86.9 (2)° with the 3-chlorobenzyl ring. In the crystal, molecules form inversion dimers connected via pairs of O—H⋯O hydrogen bonds.

Related literature

For biological activity of inhibitors for the microsomal prostaglandin E₂ synthase-1 (mPGES-1) and 5-lipoxygenase (5-LO), see: Elkady et al. (2012 ). For details of the synthesis, see: Maguire et al. (2001 ).

Experimental

Crystal data

C₁₈H₁₅BrClNO₂
M_r = 392.67
Triclinic, $[P \overline 1]$
a = 8.5386 (11) Å
b = 10.0157 (10) Å
c = 11.0821 (12) Å
α = 109.221 (8)°
β = 106.229 (9)°
γ = 101.886 (9)°
V = 811.52 (16) Å³
Z = 2
Mo Kα radiation
μ = 2.71 mm⁻¹
T = 298 K
0.44 × 0.15 × 0.12 mm

Data collection

Stoe IPDS 2T diffractometer
Absorption correction: integration (X-RED; Stoe & Cie, 2010 ) T_min = 0.388, T_max = 0.785
9139 measured reflections
4400 independent reflections
2791 reflections with I > 2σ(I)
R_int = 0.040

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.150
S = 1.02
4400 reflections
209 parameters
H-atom parameters constrained
Δρ_max = 0.72 e Å⁻³
Δρ_min = −0.69 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O18—H18⋯O17ⁱ	0.82	1.87	2.679 (3)	170
Symmetry code: (i) -x+2, -y+1, -z+2.

Data collection: X-AREA (Stoe & Cie, 2010); cell refinement: X-AREA; data reduction: X-RED (Stoe & Cie, 2010); program(s) used to solve structure: SIR97 (Altomare et al., 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: PLATON.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812046740/bt6855sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812046740/bt6855Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812046740/bt6855Isup3.cml

checkCIF report

Comment top

We synthesized and evaluated inhibitors for the microsomal prostaglandin E₂ synthase-1 (mPGES-1) and 5-lipoxygenase (5-LO) (Elkady et al., 2012). The title compound was synthesized to obtain a template which leads to series of different derivates of the indole scaffold.

The indole ring is oriented with dihedral angle of 86.9 (2)° with the 3-chlorobenzyl ring in the crystal structure. Each two molecules form centrosymmetrical dimers connected via O18–H18···O17 hydrogen bridges (O18···O17 2.679 (3) Å) (Tab.1).

Related literature top

For biological activity of inhibitors for the microsomal prostaglandin E₂ synthase-1 (mPGES-1) and 5-lipoxygenase (5-LO), see: Elkady et al. (2012). For details of the synthesis, see: Maguire et al. (2001).

Experimental top

0.2 g (0.74 mmol) of 2-(5-bromo-2-methyl-1H-indol-3-yl) acetic acid were dissolved in 5 ml dry dimethylformamide. Then 60 mg of Sodium hydride were slowly added and the mixture was stirred under argon at 273 K for 30 min (Maguire et al., 2001). Then, 0.18 ml (1.48 mmol) of 3-chlorobenzyl chloride were dissolved in 3 ml of dry dimethylformamide and this was then slowly added to the mixture and stirred for 1 h at 273 K. The reaction was stopped by quenching with ice cooled water; the pH was adjusted to 1 by 5 N aqueous hydrochloric acid. The product was extracted with ethyl acetate three times, dried over anhydrous sodium sulfate and finally concentrated under vacuum. The product was purified by washing with methanol. Crystals of the title compound were obtained by slow evaporation of methanol at room temperature.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2010); cell refinement: X-AREA (Stoe & Cie, 2010); data reduction: X-RED (Stoe & Cie, 2010); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top

Fig. 1. View of compound I. Displacement ellipsoids are drawn at the 50% probability level.

2-[5-Bromo-1-(3-chlorobenzyl)-2-methyl-1H-indol-3-yl]acetic acid top

Crystal data top

C₁₈H₁₅BrClNO₂	Z = 2
M_r = 392.67	F(000) = 396
Triclinic, P1	D_x = 1.607 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.5386 (11) Å	Cell parameters from 6836 reflections
b = 10.0157 (10) Å	θ = 2.4–29.3°
c = 11.0821 (12) Å	µ = 2.71 mm⁻¹
α = 109.221 (8)°	T = 298 K
β = 106.229 (9)°	Block, colourless
γ = 101.886 (9)°	0.44 × 0.15 × 0.12 mm
V = 811.52 (16) Å³

Data collection top

Stoe IPDS 2T diffractometer	4400 independent reflections
Radiation source: sealed Tube	2791 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.040
Detector resolution: 6.67 pixels mm^-1	θ_max = 29.3°, θ_min = 2.4°
rotation method scans	h = −11→11
Absorption correction: integration (X-RED; Stoe & Cie, 2010)	k = −13→12
T_min = 0.388, T_max = 0.785	l = −15→15
9139 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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.150	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.069P)² + 0.4677P] where P = (F_o² + 2F_c²)/3
4400 reflections	(Δ/σ)_max < 0.001
209 parameters	Δρ_max = 0.72 e Å⁻³
0 restraints	Δρ_min = −0.69 e Å⁻³

Crystal data top

C₁₈H₁₅BrClNO₂	γ = 101.886 (9)°
M_r = 392.67	V = 811.52 (16) Å³
Triclinic, P1	Z = 2
a = 8.5386 (11) Å	Mo Kα radiation
b = 10.0157 (10) Å	µ = 2.71 mm⁻¹
c = 11.0821 (12) Å	T = 298 K
α = 109.221 (8)°	0.44 × 0.15 × 0.12 mm
β = 106.229 (9)°

Data collection top

Stoe IPDS 2T diffractometer	4400 independent reflections
Absorption correction: integration (X-RED; Stoe & Cie, 2010)	2791 reflections with I > 2σ(I)
T_min = 0.388, T_max = 0.785	R_int = 0.040
9139 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.150	H-atom parameters constrained
S = 1.02	Δρ_max = 0.72 e Å⁻³
4400 reflections	Δρ_min = −0.69 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
Br1	0.98960 (7)	0.99173 (4)	0.68263 (5)	0.0811 (2)
Cl1	0.82521 (16)	0.14242 (15)	−0.02826 (13)	0.0943 (4)
N1	0.5804 (3)	0.3419 (3)	0.3758 (2)	0.0436 (5)
C1A	0.6557 (4)	0.4936 (3)	0.4301 (3)	0.0398 (6)
C2	0.6079 (4)	0.5993 (4)	0.3871 (3)	0.0478 (7)
H2	0.5097	0.5714	0.3094	0.057*
C3	0.7091 (5)	0.7457 (4)	0.4622 (3)	0.0520 (8)
H3	0.6801	0.8188	0.4351	0.062*
C4	0.8553 (5)	0.7865 (4)	0.5788 (3)	0.0516 (7)
C5	0.9056 (4)	0.6835 (4)	0.6232 (3)	0.0465 (7)
H5	1.0037	0.7130	0.7015	0.056*
C5A	0.8048 (4)	0.5337 (3)	0.5472 (3)	0.0396 (6)
C6	0.8162 (4)	0.3989 (3)	0.5604 (3)	0.0426 (6)
C7	0.6776 (4)	0.2843 (3)	0.4540 (3)	0.0458 (7)
C8	0.4319 (4)	0.2570 (4)	0.2463 (3)	0.0527 (7)
H8A	0.3432	0.3038	0.2471	0.063*
H8B	0.3848	0.1564	0.2387	0.063*
C9	0.4776 (4)	0.2482 (4)	0.1228 (3)	0.0476 (7)
C10	0.6134 (4)	0.2012 (4)	0.1056 (3)	0.0521 (7)
H10	0.6778	0.1724	0.1692	0.063*
C11	0.6520 (5)	0.1976 (4)	−0.0080 (3)	0.0602 (9)
C12	0.5554 (6)	0.2388 (5)	−0.1038 (3)	0.0733 (12)
H12	0.5833	0.2366	−0.1797	0.088*
C13	0.4217 (6)	0.2818 (5)	−0.0869 (4)	0.0765 (12)
H13	0.3560	0.3083	−0.1519	0.092*
C14	0.3804 (5)	0.2871 (5)	0.0259 (3)	0.0644 (9)
H14	0.2871	0.3169	0.0367	0.077*
C15	0.9604 (5)	0.3856 (4)	0.6627 (3)	0.0514 (7)
H15A	1.0681	0.4430	0.6646	0.062*
H15B	0.9548	0.2816	0.6302	0.062*
C16	0.9669 (4)	0.4356 (3)	0.8074 (3)	0.0436 (6)
O17	0.8593 (3)	0.4791 (3)	0.8448 (2)	0.0632 (7)
O18	1.1017 (3)	0.4268 (4)	0.8893 (2)	0.0717 (8)
H18	1.1012	0.4549	0.9675	0.108*
C19	0.6253 (6)	0.1216 (4)	0.4211 (4)	0.0663 (10)
H19A	0.7000	0.1043	0.4928	0.099*
H19B	0.6339	0.0682	0.3349	0.099*
H19C	0.5083	0.0871	0.4141	0.099*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.1083 (4)	0.0471 (2)	0.0743 (3)	0.0105 (2)	0.0368 (3)	0.01569 (18)
Cl1	0.0830 (8)	0.0973 (8)	0.0888 (8)	0.0194 (6)	0.0543 (7)	0.0096 (6)
N1	0.0509 (14)	0.0486 (13)	0.0299 (10)	0.0130 (11)	0.0149 (10)	0.0167 (10)
C1A	0.0468 (15)	0.0489 (15)	0.0299 (11)	0.0190 (12)	0.0183 (11)	0.0185 (11)
C2	0.0545 (18)	0.0626 (18)	0.0394 (14)	0.0274 (15)	0.0207 (13)	0.0289 (14)
C3	0.071 (2)	0.0532 (17)	0.0516 (17)	0.0312 (16)	0.0327 (17)	0.0310 (15)
C4	0.067 (2)	0.0444 (15)	0.0469 (16)	0.0165 (14)	0.0307 (15)	0.0172 (13)
C5	0.0494 (17)	0.0543 (17)	0.0339 (13)	0.0152 (14)	0.0171 (12)	0.0160 (12)
C5A	0.0476 (16)	0.0494 (15)	0.0287 (11)	0.0198 (12)	0.0188 (11)	0.0184 (11)
C6	0.0575 (18)	0.0530 (16)	0.0280 (12)	0.0266 (14)	0.0198 (12)	0.0213 (11)
C7	0.0638 (19)	0.0467 (15)	0.0363 (13)	0.0209 (14)	0.0264 (13)	0.0201 (12)
C8	0.0466 (17)	0.0630 (19)	0.0382 (14)	0.0075 (15)	0.0134 (13)	0.0171 (14)
C9	0.0476 (17)	0.0497 (16)	0.0304 (12)	0.0046 (13)	0.0091 (12)	0.0103 (11)
C10	0.0514 (18)	0.0563 (18)	0.0382 (14)	0.0070 (14)	0.0151 (13)	0.0149 (13)
C11	0.061 (2)	0.0509 (17)	0.0470 (17)	−0.0009 (15)	0.0243 (16)	0.0027 (14)
C12	0.092 (3)	0.074 (2)	0.0359 (16)	0.000 (2)	0.0260 (19)	0.0160 (16)
C13	0.091 (3)	0.094 (3)	0.0468 (19)	0.026 (3)	0.023 (2)	0.037 (2)
C14	0.072 (2)	0.076 (2)	0.0431 (17)	0.0236 (19)	0.0166 (16)	0.0258 (16)
C15	0.064 (2)	0.068 (2)	0.0361 (14)	0.0342 (17)	0.0225 (14)	0.0267 (14)
C16	0.0503 (17)	0.0512 (16)	0.0351 (13)	0.0191 (13)	0.0156 (12)	0.0235 (12)
O17	0.0651 (15)	0.104 (2)	0.0362 (11)	0.0458 (15)	0.0230 (11)	0.0328 (12)
O18	0.0711 (17)	0.121 (2)	0.0421 (12)	0.0550 (17)	0.0221 (12)	0.0410 (14)
C19	0.096 (3)	0.0489 (18)	0.059 (2)	0.0244 (19)	0.032 (2)	0.0248 (16)

Geometric parameters (Å, º) top

Br1—C4	1.897 (3)	C8—H8B	0.9700
Cl1—C11	1.727 (4)	C9—C10	1.376 (5)
N1—C1A	1.365 (4)	C9—C14	1.380 (5)
N1—C7	1.378 (4)	C10—C11	1.379 (5)
N1—C8	1.458 (4)	C10—H10	0.9300
C1A—C2	1.384 (4)	C11—C12	1.384 (6)
C1A—C5A	1.411 (4)	C12—C13	1.340 (7)
C2—C3	1.364 (5)	C12—H12	0.9300
C2—H2	0.9300	C13—C14	1.379 (5)
C3—C4	1.391 (5)	C13—H13	0.9300
C3—H3	0.9300	C14—H14	0.9300
C4—C5	1.375 (5)	C15—C16	1.495 (4)
C5—C5A	1.390 (4)	C15—H15A	0.9700
C5—H5	0.9300	C15—H15B	0.9700
C5A—C6	1.425 (4)	C16—O17	1.210 (4)
C6—C7	1.370 (4)	C16—O18	1.291 (4)
C6—C15	1.485 (4)	O18—H18	0.8200
C7—C19	1.485 (4)	C19—H19A	0.9600
C8—C9	1.506 (4)	C19—H19B	0.9600
C8—H8A	0.9700	C19—H19C	0.9600

C1A—N1—C7	109.2 (2)	C10—C9—C8	120.8 (3)
C1A—N1—C8	123.7 (3)	C14—C9—C8	119.1 (3)
C7—N1—C8	126.7 (3)	C9—C10—C11	118.6 (3)
N1—C1A—C2	130.6 (3)	C9—C10—H10	120.7
N1—C1A—C5A	107.6 (2)	C11—C10—H10	120.7
C2—C1A—C5A	121.8 (3)	C10—C11—C12	121.0 (4)
C3—C2—C1A	118.1 (3)	C10—C11—Cl1	118.8 (3)
C3—C2—H2	121.0	C12—C11—Cl1	120.2 (3)
C1A—C2—H2	121.0	C13—C12—C11	119.7 (3)
C2—C3—C4	120.6 (3)	C13—C12—H12	120.1
C2—C3—H3	119.7	C11—C12—H12	120.1
C4—C3—H3	119.7	C12—C13—C14	120.6 (4)
C5—C4—C3	122.4 (3)	C12—C13—H13	119.7
C5—C4—Br1	118.3 (3)	C14—C13—H13	119.7
C3—C4—Br1	119.3 (2)	C13—C14—C9	119.9 (4)
C4—C5—C5A	117.8 (3)	C13—C14—H14	120.0
C4—C5—H5	121.1	C9—C14—H14	120.0
C5A—C5—H5	121.1	C6—C15—C16	117.1 (3)
C5—C5A—C1A	119.4 (3)	C6—C15—H15A	108.0
C5—C5A—C6	133.6 (3)	C16—C15—H15A	108.0
C1A—C5A—C6	107.0 (3)	C6—C15—H15B	108.0
C7—C6—C5A	106.9 (2)	C16—C15—H15B	108.0
C7—C6—C15	127.0 (3)	H15A—C15—H15B	107.3
C5A—C6—C15	125.8 (3)	O17—C16—O18	123.3 (3)
C6—C7—N1	109.2 (3)	O17—C16—C15	124.6 (3)
C6—C7—C19	129.3 (3)	O18—C16—C15	112.0 (3)
N1—C7—C19	121.4 (3)	C16—O18—H18	109.5
N1—C8—C9	112.4 (3)	C7—C19—H19A	109.5
N1—C8—H8A	109.1	C7—C19—H19B	109.5
C9—C8—H8A	109.1	H19A—C19—H19B	109.5
N1—C8—H8B	109.1	C7—C19—H19C	109.5
C9—C8—H8B	109.1	H19A—C19—H19C	109.5
H8A—C8—H8B	107.9	H19B—C19—H19C	109.5
C10—C9—C14	120.1 (3)

C7—N1—C1A—C2	179.0 (3)	C15—C6—C7—C19	6.7 (5)
C8—N1—C1A—C2	5.5 (5)	C1A—N1—C7—C6	0.5 (3)
C7—N1—C1A—C5A	−0.5 (3)	C8—N1—C7—C6	173.8 (3)
C8—N1—C1A—C5A	−174.1 (3)	C1A—N1—C7—C19	178.9 (3)
N1—C1A—C2—C3	−179.9 (3)	C8—N1—C7—C19	−7.8 (5)
C5A—C1A—C2—C3	−0.4 (4)	C1A—N1—C8—C9	71.6 (4)
C1A—C2—C3—C4	−0.3 (5)	C7—N1—C8—C9	−100.8 (4)
C2—C3—C4—C5	0.5 (5)	N1—C8—C9—C10	51.7 (4)
C2—C3—C4—Br1	−178.6 (2)	N1—C8—C9—C14	−128.7 (3)
C3—C4—C5—C5A	0.1 (5)	C14—C9—C10—C11	1.6 (5)
Br1—C4—C5—C5A	179.2 (2)	C8—C9—C10—C11	−178.8 (3)
C4—C5—C5A—C1A	−0.8 (4)	C9—C10—C11—C12	−0.7 (5)
C4—C5—C5A—C6	179.5 (3)	C9—C10—C11—Cl1	178.7 (3)
N1—C1A—C5A—C5	−179.4 (2)	C10—C11—C12—C13	−0.5 (6)
C2—C1A—C5A—C5	1.0 (4)	Cl1—C11—C12—C13	−179.8 (3)
N1—C1A—C5A—C6	0.3 (3)	C11—C12—C13—C14	0.7 (7)
C2—C1A—C5A—C6	−179.2 (3)	C12—C13—C14—C9	0.1 (7)
C5—C5A—C6—C7	179.6 (3)	C10—C9—C14—C13	−1.3 (6)
C1A—C5A—C6—C7	−0.1 (3)	C8—C9—C14—C13	179.1 (4)
C5—C5A—C6—C15	−5.5 (5)	C7—C6—C15—C16	−109.5 (4)
C1A—C5A—C6—C15	174.9 (3)	C5A—C6—C15—C16	76.6 (4)
C5A—C6—C7—N1	−0.2 (3)	C6—C15—C16—O17	3.5 (5)
C15—C6—C7—N1	−175.1 (3)	C6—C15—C16—O18	−176.6 (3)
C5A—C6—C7—C19	−178.5 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O18—H18···O17ⁱ	0.82	1.87	2.679 (3)	170

Symmetry code: (i) −x+2, −y+1, −z+2.

Experimental details

Crystal data
Chemical formula	C₁₈H₁₅BrClNO₂
M_r	392.67
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.5386 (11), 10.0157 (10), 11.0821 (12)
α, β, γ (°)	109.221 (8), 106.229 (9), 101.886 (9)
V (Å³)	811.52 (16)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	2.71
Crystal size (mm)	0.44 × 0.15 × 0.12

Data collection
Diffractometer	Stoe IPDS 2T diffractometer
Absorption correction	Integration (X-RED; Stoe & Cie, 2010)
T_min, T_max	0.388, 0.785
No. of measured, independent and observed [I > 2σ(I)] reflections	9139, 4400, 2791
R_int	0.040
(sin θ/λ)_max (Å⁻¹)	0.689

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.150, 1.02
No. of reflections	4400
No. of parameters	209
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.72, −0.69

Computer programs: X-AREA (Stoe & Cie, 2010), X-RED (Stoe & Cie, 2010), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O18—H18···O17ⁱ	0.82	1.87	2.679 (3)	170

Symmetry code: (i) −x+2, −y+1, −z+2.

Acknowledgements

This research was supported financially by the Landesgraduiertenförderung program of the Ministry of Science, Research and Arts of the state of Baden-Württemberg, Germany.

References

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