Methyl 3-[(1-butyl-1H-indol-3-yl)carbonyl­amino]propionate

Huang, G.; Xu, X.Y.; Zeng, X.C.; Tang, G.H.; Li, D.D.

doi:10.1107/S1600536809029973

organic compounds

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ISSN: 2056-9890

Volume 65| Part 9| September 2009| Page o2063

doi:10.1107/S1600536809029973

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Methyl 3-[(1-butyl-1H-indol-3-yl)carbonylamino]propionate

Gang Huang,^a Xing Yan Xu,^a Xiang Chao Zeng,^a ^* Gui Hong Tang ^a and Dong Dong Li ^a

^aDepartment of Chemistry, Jinan University, Guangzhou, Guangdong 510632, People's Republic of China
^*Correspondence e-mail: xczeng@126.com

(Received 22 July 2009; accepted 28 July 2009; online 8 August 2009)

In the title molecule, C₁₇H₂₂N₂O₃, the mean plane of the terminal (C=O)OMe fragment and the indole plane form a dihedral angle of 78.94 (3)°. Intermolecular N—H⋯O hydrogen bonds link the molecules into chains extended along the c axis. The crystal packing exhibits π–π interactions, indicated by the short distance of 3.472 (2) Å between the centroids of the five-membered heterocycles of neighbouring molecules.

Related literature

For the bioactivity of indole derivatives, see: Fabio et al. (2007 ); Sharma et al. (2004 ). For related structures, see: Zeng et al. (2005 ); Siddiquee et al. (2009 ).

Experimental

Crystal data

C₁₇H₂₂N₂O₃
M_r = 302.37
Monoclinic, P 2₁ /c
a = 14.144 (3) Å
b = 12.685 (3) Å
c = 9.198 (2) Å
β = 107.151 (4)°
V = 1576.8 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 173 K
0.46 × 0.42 × 0.17 mm

Data collection

Bruker SMART 1K CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.961, T_max = 0.985
7760 measured reflections
3093 independent reflections
2169 reflections with I > 2σ(I)
R_int = 0.037

Refinement

R[F² > 2σ(F²)] = 0.045
wR(F²) = 0.135
S = 1.05
3093 reflections
201 parameters
H-atom parameters constrained
Δρ_max = 0.23 e Å⁻³
Δρ_min = −0.27 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N2—H2⋯O1ⁱ	0.88	2.07	2.860 (2)	149
Symmetry code: (i) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: SMART (Bruker,1999 ); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809029973/cv2594sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809029973/cv2594Isup2.hkl

checkCIF report

Comment top

Many indole derivatives show important bioactivities, such as metabotropic receptor antagonists (Fabio et al., 2007) and protein kinase inhibiting activity (Sharma et al., 2004). In continuation of our previous structural investigations of 3-trichloroacetylindole (Zeng et al., 2005), we report here the crystal structure of the title compound, (I).

In (I) (Fig.1), all bond lengths and angles are unexceptional and correspond to those observed in the related compounds (Zeng et al., 2005; Siddiquee et al., 2009). In the crystal structure, adjacent molecules are linked through N2—H2A···O1 hydrogen bonds, forming chains extending along the c axis. The crystal packing exhibits π–π interactions proved by short distance of 3.472 (2) Å between the centroids of five-membered heterocycles of the neighbouring molecules.

Related literature top

For the bioactivity of indole derivatives, see: Fabio et al. (2007); Sharma et al. (2004). For related structures, see: Zeng et al. (2005); Siddiquee et al. (2009).

Experimental top

A suspension of potassium carbonate (1.80 g, 13.0 mmol), 1-bromobutane (0.35 ml, 3.25 mmol) and methyl 3-(1H-Indole-3-carbonyl)aminopropionate (0.80 g, 3.25 mmol) in acetonitrile (30 ml) magnetically stirred at 328 K for 72 h. After filtration, the filtrate was evaporated in vacuo, and the residue was recrystallized with ethanol/water solution (1:1 v/v). Then the recrystallized solid was further purified by column chromatography on silica gel (petroleum ether/EtOAc, 1:1 v/v) to yield I (m.p. 367 K, 91.6%). Colourless crystals suitable for X-ray analysis were obtained over a period of five days by slow evaporation at room temperature of a petroleum ether/EtOAc solution (1:1 v/v).

Computing details top

Data collection: SMART (Bruker,1999); cell refinement: SAINT-Plus (Bruker, 1999); data reduction: SAINT-Plus (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of the title compound, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.

Methyl 3-[(1-butyl-1H-indol-3-yl)carbonylamino]propionate top

Crystal data top

C₁₇H₂₂N₂O₃	D_x = 1.274 Mg m⁻³
M_r = 302.37	Melting point: 367 K
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 14.144 (3) Å	Cell parameters from 2799 reflections
b = 12.685 (3) Å	θ = 2.8–26.9°
c = 9.198 (2) Å	µ = 0.09 mm⁻¹
β = 107.151 (4)°	T = 173 K
V = 1576.8 (6) Å³	Plate, colourless
Z = 4	0.46 × 0.42 × 0.17 mm
F(000) = 648

Data collection top

Bruker SMART 1K CCD area-detector diffractometer	3093 independent reflections
Radiation source: fine-focus sealed tube	2169 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.037
ϕ and ω scans	θ_max = 26.0°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −17→9
T_min = 0.961, T_max = 0.985	k = −15→13
7760 measured reflections	l = −11→10

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)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.135	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0677P)² + 0.3821P] where P = (F_o² + 2F_c²)/3
3093 reflections	(Δ/σ)_max = 0.001
201 parameters	Δρ_max = 0.23 e Å⁻³
0 restraints	Δρ_min = −0.27 e Å⁻³

Crystal data top

C₁₇H₂₂N₂O₃	V = 1576.8 (6) Å³
M_r = 302.37	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 14.144 (3) Å	µ = 0.09 mm⁻¹
b = 12.685 (3) Å	T = 173 K
c = 9.198 (2) Å	0.46 × 0.42 × 0.17 mm
β = 107.151 (4)°

Data collection top

Bruker SMART 1K CCD area-detector diffractometer	3093 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	2169 reflections with I > 2σ(I)
T_min = 0.961, T_max = 0.985	R_int = 0.037
7760 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.045	0 restraints
wR(F²) = 0.135	H-atom parameters constrained
S = 1.05	Δρ_max = 0.23 e Å⁻³
3093 reflections	Δρ_min = −0.27 e Å⁻³
201 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
O1	0.32207 (9)	0.17769 (11)	1.18054 (15)	0.0326 (3)
N2	0.27815 (11)	0.22657 (13)	0.93470 (18)	0.0286 (4)
H2	0.2944	0.2301	0.8495	0.034*
N1	0.56995 (11)	0.12769 (12)	0.95991 (17)	0.0271 (4)
O2	0.07347 (10)	0.00166 (12)	0.83159 (18)	0.0431 (4)
C1	0.47775 (13)	0.16910 (14)	0.9284 (2)	0.0255 (4)
H1	0.4419	0.1987	0.8331	0.031*
C2	0.44315 (13)	0.16250 (14)	1.0527 (2)	0.0251 (4)
O3	0.06776 (13)	0.13614 (14)	0.67382 (18)	0.0545 (5)
C3	0.52016 (13)	0.11227 (14)	1.1707 (2)	0.0259 (4)
C9	0.34451 (13)	0.19061 (15)	1.0605 (2)	0.0258 (4)
C4	0.53054 (14)	0.07969 (15)	1.3199 (2)	0.0300 (4)
H4	0.4797	0.0931	1.3659	0.036*
C12	0.08303 (14)	0.10345 (18)	0.8007 (2)	0.0343 (5)
C14	0.62646 (14)	0.11611 (16)	0.8515 (2)	0.0292 (4)
H14A	0.5822	0.1302	0.7479	0.035*
H14B	0.6494	0.0422	0.8539	0.035*
C7	0.68374 (14)	0.03955 (15)	1.1879 (2)	0.0312 (5)
H7	0.7354	0.0266	1.1436	0.037*
C8	0.59785 (13)	0.09149 (14)	1.1080 (2)	0.0255 (4)
C11	0.11220 (14)	0.16838 (17)	0.9426 (2)	0.0328 (5)
H11A	0.1460	0.1225	1.0294	0.039*
H11B	0.0517	0.1965	0.9619	0.039*
C10	0.18006 (13)	0.25988 (16)	0.9350 (2)	0.0310 (5)
H10A	0.1496	0.3012	0.8416	0.037*
H10B	0.1862	0.3068	1.0234	0.037*
C15	0.71526 (14)	0.18848 (16)	0.8815 (2)	0.0300 (5)
H15A	0.7627	0.1708	0.9813	0.036*
H15B	0.6936	0.2623	0.8862	0.036*
C16	0.76656 (15)	0.17862 (17)	0.7580 (2)	0.0364 (5)
H16A	0.7164	0.1870	0.6576	0.044*
H16B	0.8146	0.2371	0.7698	0.044*
C5	0.61526 (15)	0.02801 (16)	1.3987 (2)	0.0345 (5)
H5	0.6227	0.0055	1.4999	0.041*
C6	0.69128 (15)	0.00763 (16)	1.3333 (2)	0.0353 (5)
H6	0.7489	−0.0288	1.3906	0.042*
C17	0.82035 (16)	0.07542 (19)	0.7591 (3)	0.0455 (6)
H17A	0.8722	0.0676	0.8564	0.068*
H17B	0.8504	0.0749	0.6757	0.068*
H17C	0.7734	0.0169	0.7461	0.068*
C13	0.04133 (18)	−0.0678 (2)	0.7031 (3)	0.0564 (7)
H13A	−0.0213	−0.0421	0.6344	0.085*
H13B	0.0319	−0.1389	0.7382	0.085*
H13C	0.0915	−0.0698	0.6489	0.085*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0298 (7)	0.0442 (9)	0.0277 (7)	−0.0011 (6)	0.0144 (6)	−0.0037 (6)
N2	0.0250 (8)	0.0355 (9)	0.0278 (9)	0.0011 (7)	0.0117 (7)	−0.0009 (7)
N1	0.0256 (8)	0.0307 (9)	0.0281 (9)	0.0003 (7)	0.0124 (7)	−0.0005 (7)
O2	0.0347 (8)	0.0382 (9)	0.0536 (10)	−0.0014 (7)	0.0088 (7)	−0.0073 (7)
C1	0.0233 (9)	0.0261 (10)	0.0274 (10)	0.0004 (8)	0.0078 (8)	0.0002 (8)
C2	0.0251 (9)	0.0247 (10)	0.0266 (10)	−0.0027 (8)	0.0095 (8)	−0.0022 (8)
O3	0.0636 (11)	0.0652 (12)	0.0348 (9)	−0.0229 (9)	0.0148 (8)	−0.0042 (8)
C3	0.0255 (10)	0.0233 (9)	0.0301 (10)	−0.0034 (8)	0.0100 (8)	−0.0026 (8)
C9	0.0269 (10)	0.0252 (10)	0.0272 (10)	−0.0047 (8)	0.0107 (8)	−0.0061 (8)
C4	0.0307 (10)	0.0299 (10)	0.0312 (10)	−0.0062 (8)	0.0122 (8)	−0.0014 (8)
C12	0.0216 (10)	0.0450 (13)	0.0387 (12)	−0.0051 (9)	0.0128 (9)	−0.0032 (10)
C14	0.0282 (10)	0.0329 (11)	0.0307 (11)	0.0002 (8)	0.0152 (8)	−0.0041 (8)
C7	0.0273 (10)	0.0287 (10)	0.0385 (12)	0.0001 (8)	0.0109 (9)	−0.0005 (9)
C8	0.0254 (10)	0.0221 (9)	0.0297 (10)	−0.0039 (7)	0.0089 (8)	−0.0034 (8)
C11	0.0255 (10)	0.0413 (12)	0.0341 (11)	−0.0018 (9)	0.0129 (8)	−0.0013 (9)
C10	0.0246 (10)	0.0323 (11)	0.0377 (11)	0.0024 (8)	0.0116 (8)	−0.0032 (9)
C15	0.0303 (10)	0.0304 (10)	0.0333 (11)	−0.0004 (8)	0.0158 (8)	−0.0008 (8)
C16	0.0354 (11)	0.0419 (12)	0.0371 (12)	−0.0047 (9)	0.0187 (9)	0.0014 (9)
C5	0.0388 (12)	0.0337 (11)	0.0293 (11)	−0.0044 (9)	0.0074 (9)	0.0054 (9)
C6	0.0321 (11)	0.0300 (11)	0.0401 (12)	0.0014 (9)	0.0049 (9)	0.0055 (9)
C17	0.0348 (12)	0.0590 (16)	0.0483 (14)	0.0078 (11)	0.0211 (11)	−0.0015 (11)
C13	0.0407 (13)	0.0510 (15)	0.0742 (18)	−0.0051 (11)	0.0118 (12)	−0.0255 (13)

Geometric parameters (Å, º) top

O1—C9	1.247 (2)	C7—C8	1.387 (3)
N2—C9	1.337 (2)	C7—H7	0.9500
N2—C10	1.451 (2)	C11—C10	1.521 (3)
N2—H2	0.8800	C11—H11A	0.9900
N1—C1	1.356 (2)	C11—H11B	0.9900
N1—C8	1.380 (2)	C10—H10A	0.9900
N1—C14	1.458 (2)	C10—H10B	0.9900
O2—C12	1.337 (3)	C15—C16	1.523 (3)
O2—C13	1.436 (3)	C15—H15A	0.9900
C1—C2	1.373 (3)	C15—H15B	0.9900
C1—H1	0.9500	C16—C17	1.513 (3)
C2—C3	1.440 (3)	C16—H16A	0.9900
C2—C9	1.462 (3)	C16—H16B	0.9900
O3—C12	1.197 (2)	C5—C6	1.402 (3)
C3—C4	1.399 (3)	C5—H5	0.9500
C3—C8	1.408 (3)	C6—H6	0.9500
C4—C5	1.371 (3)	C17—H17A	0.9800
C4—H4	0.9500	C17—H17B	0.9800
C12—C11	1.495 (3)	C17—H17C	0.9800
C14—C15	1.514 (3)	C13—H13A	0.9800
C14—H14A	0.9900	C13—H13B	0.9800
C14—H14B	0.9900	C13—H13C	0.9800
C7—C6	1.371 (3)

C9—N2—C10	121.69 (16)	C12—C11—H11B	108.9
C9—N2—H2	119.2	C10—C11—H11B	108.9
C10—N2—H2	119.2	H11A—C11—H11B	107.7
C1—N1—C8	108.50 (15)	N2—C10—C11	113.24 (16)
C1—N1—C14	125.40 (16)	N2—C10—H10A	108.9
C8—N1—C14	125.93 (16)	C11—C10—H10A	108.9
C12—O2—C13	116.39 (19)	N2—C10—H10B	108.9
N1—C1—C2	110.77 (16)	C11—C10—H10B	108.9
N1—C1—H1	124.6	H10A—C10—H10B	107.7
C2—C1—H1	124.6	C14—C15—C16	111.46 (16)
C1—C2—C3	106.16 (16)	C14—C15—H15A	109.3
C1—C2—C9	127.25 (17)	C16—C15—H15A	109.3
C3—C2—C9	126.32 (16)	C14—C15—H15B	109.3
C4—C3—C8	118.55 (17)	C16—C15—H15B	109.3
C4—C3—C2	135.00 (17)	H15A—C15—H15B	108.0
C8—C3—C2	106.41 (16)	C17—C16—C15	114.53 (17)
O1—C9—N2	120.95 (17)	C17—C16—H16A	108.6
O1—C9—C2	120.46 (17)	C15—C16—H16A	108.6
N2—C9—C2	118.54 (16)	C17—C16—H16B	108.6
C5—C4—C3	118.83 (18)	C15—C16—H16B	108.6
C5—C4—H4	120.6	H16A—C16—H16B	107.6
C3—C4—H4	120.6	C4—C5—C6	121.53 (19)
O3—C12—O2	122.8 (2)	C4—C5—H5	119.2
O3—C12—C11	125.8 (2)	C6—C5—H5	119.2
O2—C12—C11	111.45 (18)	C7—C6—C5	121.00 (18)
N1—C14—C15	113.98 (15)	C7—C6—H6	119.5
N1—C14—H14A	108.8	C5—C6—H6	119.5
C15—C14—H14A	108.8	C16—C17—H17A	109.5
N1—C14—H14B	108.8	C16—C17—H17B	109.5
C15—C14—H14B	108.8	H17A—C17—H17B	109.5
H14A—C14—H14B	107.7	C16—C17—H17C	109.5
C6—C7—C8	117.49 (18)	H17A—C17—H17C	109.5
C6—C7—H7	121.3	H17B—C17—H17C	109.5
C8—C7—H7	121.3	O2—C13—H13A	109.5
N1—C8—C7	129.22 (17)	O2—C13—H13B	109.5
N1—C8—C3	108.14 (16)	H13A—C13—H13B	109.5
C7—C8—C3	122.60 (18)	O2—C13—H13C	109.5
C12—C11—C10	113.33 (16)	H13A—C13—H13C	109.5
C12—C11—H11A	108.9	H13B—C13—H13C	109.5
C10—C11—H11A	108.9

C8—N1—C1—C2	0.6 (2)	C1—N1—C8—C7	177.15 (19)
C14—N1—C1—C2	176.18 (16)	C14—N1—C8—C7	1.6 (3)
N1—C1—C2—C3	−0.4 (2)	C1—N1—C8—C3	−0.6 (2)
N1—C1—C2—C9	−174.69 (17)	C14—N1—C8—C3	−176.13 (16)
C1—C2—C3—C4	−177.5 (2)	C6—C7—C8—N1	−177.13 (18)
C9—C2—C3—C4	−3.0 (3)	C6—C7—C8—C3	0.3 (3)
C1—C2—C3—C8	0.0 (2)	C4—C3—C8—N1	178.29 (16)
C9—C2—C3—C8	174.42 (17)	C2—C3—C8—N1	0.3 (2)
C10—N2—C9—O1	4.9 (3)	C4—C3—C8—C7	0.4 (3)
C10—N2—C9—C2	−177.58 (16)	C2—C3—C8—C7	−177.55 (17)
C1—C2—C9—O1	177.91 (18)	O3—C12—C11—C10	−35.6 (3)
C3—C2—C9—O1	4.7 (3)	O2—C12—C11—C10	145.76 (17)
C1—C2—C9—N2	0.4 (3)	C9—N2—C10—C11	−74.0 (2)
C3—C2—C9—N2	−172.86 (17)	C12—C11—C10—N2	−69.1 (2)
C8—C3—C4—C5	−0.6 (3)	N1—C14—C15—C16	−175.70 (16)
C2—C3—C4—C5	176.6 (2)	C14—C15—C16—C17	−70.2 (2)
C13—O2—C12—O3	−1.3 (3)	C3—C4—C5—C6	0.2 (3)
C13—O2—C12—C11	177.36 (17)	C8—C7—C6—C5	−0.7 (3)
C1—N1—C14—C15	110.6 (2)	C4—C5—C6—C7	0.5 (3)
C8—N1—C14—C15	−74.5 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O1ⁱ	0.88	2.07	2.860 (2)	149

Symmetry code: (i) x, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₁₇H₂₂N₂O₃
M_r	302.37
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	173
a, b, c (Å)	14.144 (3), 12.685 (3), 9.198 (2)
β (°)	107.151 (4)
V (Å³)	1576.8 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.46 × 0.42 × 0.17

Data collection
Diffractometer	Bruker SMART 1K CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.961, 0.985
No. of measured, independent and observed [I > 2σ(I)] reflections	7760, 3093, 2169
R_int	0.037
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.045, 0.135, 1.05
No. of reflections	3093
No. of parameters	201
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.23, −0.27

Computer programs: SMART (Bruker,1999), SAINT-Plus (Bruker, 1999), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2···O1ⁱ	0.88	2.07	2.860 (2)	148.6

Symmetry code: (i) x, −y+1/2, z−1/2.

Acknowledgements

We thank the Natural Science Foundation of Guangdong Province, China (grant No. 06300581) for generous support of this study.

References

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