Ethyl 2-benzoyl-6-methyl­indolizine-7-carboxyl­ate

Liao, S.-T.

doi:10.1107/S1600536812016212

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 5| May 2012| Page o1457

doi:10.1107/S1600536812016212

Open

access

Ethyl 2-benzoyl-6-methylindolizine-7-carboxylate

Shang-Tie Liao ^a ^*

^aSchool of New Energy Science and Engineering, Xinyu University, Xinyu 338000, People's Republic of China, and, Key Laboratory of Jiangxi University for Silicon Materials, Xinyu 338000, People's Republic of China
^*Correspondence e-mail: liaoshangtie@163.com

(Received 30 March 2012; accepted 14 April 2012; online 21 April 2012)

The title compound, C₁₉H₁₇NO₃, was synthesized using a tandem annulation reaction between 4-benzoyl-1H-pyrrole-2-carbaldehyde and (E)-ethyl 4-bromobut-2-enoate under mild conditions. The dihedral angle between the benzene ring and the indolizine ring system is 41.73 (4)°.

Related literature

For background to indolizines, see:Ge et al. (2009a , 2011 ). For bond lengths and angles in related structures, see: Ge et al. (2009b ). For the synthesis of imidazo[1,2-a]pyridines via a tandem reaction, see: Jia et al. (2010 ).

Experimental

Crystal data

C₁₉H₁₇NO₃
M_r = 307.34
Monoclinic, P 2₁ /n
a = 8.177 (5) Å
b = 17.243 (5) Å
c = 11.191 (5) Å
β = 102.070 (5)°
V = 1543.0 (13) Å³
Z = 4
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 K
0.18 × 0.15 × 0.14 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2005 ) T_min = 0.983, T_max = 0.990
8583 measured reflections
3150 independent reflections
2434 reflections with I > 2σ(I)
R_int = 0.124

Refinement

R[F² > 2σ(F²)] = 0.056
wR(F²) = 0.166
S = 1.04
3150 reflections
211 parameters
H-atom parameters constrained
Δρ_max = 0.30 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536812016212/hg5204sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812016212/hg5204Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812016212/hg5204Isup3.cml

checkCIF report

Comment top

Indolizines have attracted considerable attention from medicinal and organic chemists because of the interesting similarities and diversions in structure to indole (Ge et al.; 2009a, 2011). Synthetic indolizines play important roles as calcium entry blockers, potential central nervous system depressants, 5-HT3 receptor antagonist, histamine H3 receptor antagonists, cardiovascular agents, and PLA2 inhibitors. They have also drawn much attention owing to their possible usage as dyes and chemosensors. The title indolizine (I) (Fig. 1) was synthesized in order to study its biological properties. (I) was screened for anticancer activities and found to be inactive. We report here the crystal structure of the title compound. In the title compound, C₁₉H₁₇NO₃, all bond lengths and angles show normal values (Ge et al., 2009b). The dihedral angle between the benzene and indolizine rings is 41.73 (4)°.

Related literature top

For background to indolizines, see:Ge et al. (2009a, 2011). For bond lengths and angles in related structures, see: Ge et al. (2009b). For the synthesis of imidazo[1,2-a]pyridines via a tandem reaction, see: Jia et al. (2010).

Experimental top

To a 50 ml round-bottomed flask were added 4-benzoyl-1H-pyrrole-2-carbaldehyde (1.00 mmol), (E)-ethyl 4-bromobut-2-enoate (2.00 mmol), potassium carbonate (0.28 g, 2.05 mmol) and dry DMF (10 ml). The mixture was stirred at room temperature for 8 h. The solvent was removed under reduced pressure and an product was isolated by column chromatography on silica gel (yield 76%). Crystals of (I) suitable for X-ray diffraction were obtained by allowing a refluxed solution of the product in ethyl acetate to cool slowly to room temperature (without temperature control) and allowing the solvent to evaporate for 10 d.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure of (I), showing displacement ellipsoids drawn at the 50% probability level.

Ethyl 2-benzoyl-6-methylindolizine-7-carboxylate top

Crystal data top

C₁₉H₁₇NO₃	F(000) = 648
M_r = 307.34	D_x = 1.323 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2yn	Cell parameters from 4026 reflections
a = 8.177 (5) Å	θ = 2.4–28.4°
b = 17.243 (5) Å	µ = 0.09 mm⁻¹
c = 11.191 (5) Å	T = 293 K
β = 102.070 (5)°	Block, yellow
V = 1543.0 (13) Å³	0.18 × 0.15 × 0.14 mm
Z = 4

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3150 independent reflections
Radiation source: fine-focus sealed tube	2434 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.124
phi and ω scans	θ_max = 26.4°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −10→10
T_min = 0.983, T_max = 0.990	k = −17→21
8583 measured reflections	l = −13→9

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.056	H-atom parameters constrained
wR(F²) = 0.166	w = 1/[σ²(F_o²) + (0.0781P)² + 0.2178P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
3150 reflections	Δρ_max = 0.30 e Å⁻³
211 parameters	Δρ_min = −0.22 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.023 (4)

Crystal data top

C₁₉H₁₇NO₃	V = 1543.0 (13) Å³
M_r = 307.34	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.177 (5) Å	µ = 0.09 mm⁻¹
b = 17.243 (5) Å	T = 293 K
c = 11.191 (5) Å	0.18 × 0.15 × 0.14 mm
β = 102.070 (5)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3150 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2005)	2434 reflections with I > 2σ(I)
T_min = 0.983, T_max = 0.990	R_int = 0.124
8583 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.056	0 restraints
wR(F²) = 0.166	H-atom parameters constrained
S = 1.04	Δρ_max = 0.30 e Å⁻³
3150 reflections	Δρ_min = −0.22 e Å⁻³
211 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	0.5745 (2)	0.16484 (10)	1.05807 (18)	0.0509 (5)
H1	0.6122	0.1859	0.9922	0.061*
C2	0.4798 (3)	0.09802 (12)	1.0431 (2)	0.0657 (6)
H2	0.4536	0.0743	0.9668	0.079*
C3	0.4235 (3)	0.06598 (12)	1.1396 (2)	0.0694 (7)
H3	0.3572	0.0217	1.1282	0.083*
C4	0.4657 (3)	0.09960 (13)	1.2523 (2)	0.0649 (6)
H4	0.4298	0.0773	1.3180	0.078*
C5	0.5610 (2)	0.16633 (11)	1.26986 (19)	0.0522 (5)
H5	0.5901	0.1884	1.3472	0.063*
C6	0.61349 (19)	0.20050 (9)	1.17163 (16)	0.0419 (4)
C7	0.7090 (2)	0.27484 (10)	1.19416 (16)	0.0430 (4)
C8	0.6858 (2)	0.33474 (9)	1.09863 (16)	0.0411 (4)
C9	0.5640 (2)	0.33689 (9)	0.99243 (17)	0.0430 (4)
H9	0.4831	0.2992	0.9663	0.052*
C10	0.7812 (2)	0.40322 (9)	1.10421 (16)	0.0432 (4)
H10	0.8712	0.4169	1.1662	0.052*
C11	0.71730 (19)	0.44609 (9)	1.00163 (15)	0.0397 (4)
C12	0.7536 (2)	0.51834 (9)	0.95286 (17)	0.0426 (4)
H12	0.8394	0.5488	0.9967	0.051*
C13	0.4925 (2)	0.43088 (10)	0.82315 (17)	0.0459 (4)
H13	0.4036	0.4015	0.7811	0.055*
C14	0.5288 (2)	0.49875 (10)	0.77489 (16)	0.0454 (4)
C15	0.6659 (2)	0.54404 (9)	0.84358 (16)	0.0432 (4)
C16	0.4222 (3)	0.52534 (12)	0.6562 (2)	0.0625 (6)
H16A	0.3335	0.4888	0.6298	0.094*
H16B	0.4894	0.5290	0.5955	0.094*
H16C	0.3756	0.5753	0.6672	0.094*
C17	0.7185 (2)	0.61723 (11)	0.79141 (19)	0.0533 (5)
C18	0.8515 (2)	0.73858 (11)	0.8309 (2)	0.0616 (6)
H18A	0.7597	0.7674	0.7816	0.074*
H18B	0.9315	0.7264	0.7807	0.074*
C19	0.9329 (3)	0.78540 (12)	0.9384 (3)	0.0786 (7)
H19A	0.8522	0.7980	0.9865	0.118*
H19B	0.9765	0.8323	0.9110	0.118*
H19C	1.0225	0.7561	0.9870	0.118*
N1	0.58336 (16)	0.40372 (7)	0.93311 (12)	0.0394 (4)
O1	0.80406 (17)	0.28578 (8)	1.29271 (13)	0.0604 (4)
O2	0.7043 (3)	0.62853 (11)	0.68326 (16)	0.0966 (7)
O3	0.78952 (16)	0.66744 (7)	0.87619 (13)	0.0533 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0701 (11)	0.0331 (8)	0.0482 (11)	0.0025 (8)	0.0096 (8)	0.0030 (8)
C2	0.0881 (14)	0.0369 (9)	0.0660 (14)	−0.0047 (9)	0.0019 (11)	−0.0014 (9)
C3	0.0727 (13)	0.0413 (10)	0.0886 (18)	−0.0103 (9)	0.0041 (12)	0.0131 (11)
C4	0.0664 (12)	0.0542 (11)	0.0764 (15)	−0.0043 (9)	0.0202 (11)	0.0244 (11)
C5	0.0586 (10)	0.0493 (10)	0.0496 (11)	0.0033 (8)	0.0135 (8)	0.0081 (9)
C6	0.0465 (8)	0.0341 (8)	0.0451 (10)	0.0052 (6)	0.0094 (7)	0.0063 (7)
C7	0.0478 (8)	0.0384 (8)	0.0428 (10)	0.0027 (7)	0.0097 (7)	0.0009 (7)
C8	0.0484 (8)	0.0303 (8)	0.0447 (10)	0.0021 (6)	0.0097 (7)	−0.0028 (7)
C9	0.0485 (9)	0.0307 (8)	0.0493 (10)	−0.0017 (6)	0.0094 (7)	−0.0007 (7)
C10	0.0511 (9)	0.0346 (8)	0.0419 (10)	−0.0017 (7)	0.0049 (7)	−0.0040 (7)
C11	0.0457 (8)	0.0308 (8)	0.0424 (9)	0.0003 (6)	0.0088 (7)	−0.0056 (7)
C12	0.0506 (9)	0.0307 (8)	0.0469 (10)	−0.0021 (7)	0.0115 (7)	−0.0046 (7)
C13	0.0497 (9)	0.0399 (9)	0.0450 (10)	0.0019 (7)	0.0026 (7)	−0.0038 (8)
C14	0.0544 (9)	0.0392 (9)	0.0429 (10)	0.0078 (7)	0.0105 (7)	−0.0032 (7)
C15	0.0534 (9)	0.0329 (8)	0.0460 (10)	0.0048 (7)	0.0163 (7)	−0.0016 (7)
C16	0.0757 (13)	0.0548 (11)	0.0511 (12)	0.0037 (10)	−0.0005 (10)	0.0053 (10)
C17	0.0625 (11)	0.0446 (10)	0.0538 (12)	0.0022 (8)	0.0146 (9)	0.0094 (9)
C18	0.0614 (11)	0.0425 (10)	0.0830 (16)	−0.0018 (8)	0.0202 (10)	0.0214 (10)
C19	0.0987 (16)	0.0453 (11)	0.0980 (19)	−0.0186 (12)	0.0344 (14)	0.0007 (12)
N1	0.0462 (7)	0.0303 (7)	0.0412 (8)	0.0017 (5)	0.0077 (6)	−0.0027 (6)
O1	0.0713 (8)	0.0561 (8)	0.0481 (8)	−0.0085 (6)	−0.0003 (6)	0.0048 (6)
O2	0.1448 (16)	0.0845 (13)	0.0577 (11)	−0.0378 (12)	0.0149 (10)	0.0161 (10)
O3	0.0681 (8)	0.0339 (6)	0.0612 (9)	−0.0057 (5)	0.0208 (6)	0.0044 (6)

Geometric parameters (Å, º) top

C1—C2	1.379 (3)	C11—C12	1.416 (2)
C1—C6	1.388 (3)	C12—C15	1.356 (2)
C1—H1	0.9300	C12—H12	0.9300
C2—C3	1.375 (3)	C13—C14	1.348 (3)
C2—H2	0.9300	C13—N1	1.380 (2)
C3—C4	1.365 (4)	C13—H13	0.9300
C3—H3	0.9300	C14—C15	1.448 (2)
C4—C5	1.381 (3)	C14—C16	1.500 (3)
C4—H4	0.9300	C15—C17	1.491 (2)
C5—C6	1.392 (3)	C16—H16A	0.9600
C5—H5	0.9300	C16—H16B	0.9600
C6—C7	1.495 (2)	C16—H16C	0.9600
C7—O1	1.224 (2)	C17—O2	1.207 (3)
C7—C8	1.470 (2)	C17—O3	1.326 (2)
C8—C9	1.382 (2)	C18—O3	1.458 (2)
C8—C10	1.409 (2)	C18—C19	1.485 (3)
C9—N1	1.356 (2)	C18—H18A	0.9700
C9—H9	0.9300	C18—H18B	0.9700
C10—C11	1.373 (2)	C19—H19A	0.9600
C10—H10	0.9300	C19—H19B	0.9600
C11—N1	1.404 (2)	C19—H19C	0.9600

C2—C1—C6	119.8 (2)	C11—C12—H12	119.3
C2—C1—H1	120.1	C14—C13—N1	121.98 (15)
C6—C1—H1	120.1	C14—C13—H13	119.0
C3—C2—C1	120.8 (2)	N1—C13—H13	119.0
C3—C2—H2	119.6	C13—C14—C15	117.81 (16)
C1—C2—H2	119.6	C13—C14—C16	118.96 (16)
C4—C3—C2	119.6 (2)	C15—C14—C16	123.17 (16)
C4—C3—H3	120.2	C12—C15—C14	120.47 (16)
C2—C3—H3	120.2	C12—C15—C17	119.22 (16)
C3—C4—C5	120.8 (2)	C14—C15—C17	120.21 (16)
C3—C4—H4	119.6	C14—C16—H16A	109.5
C5—C4—H4	119.6	C14—C16—H16B	109.5
C4—C5—C6	119.9 (2)	H16A—C16—H16B	109.5
C4—C5—H5	120.1	C14—C16—H16C	109.5
C6—C5—H5	120.1	H16A—C16—H16C	109.5
C1—C6—C5	119.08 (17)	H16B—C16—H16C	109.5
C1—C6—C7	123.12 (16)	O2—C17—O3	123.24 (18)
C5—C6—C7	117.79 (16)	O2—C17—C15	123.64 (19)
O1—C7—C8	120.54 (16)	O3—C17—C15	113.05 (17)
O1—C7—C6	119.69 (16)	O3—C18—C19	107.76 (18)
C8—C7—C6	119.76 (14)	O3—C18—H18A	110.2
C9—C8—C10	107.95 (15)	C19—C18—H18A	110.2
C9—C8—C7	127.19 (15)	O3—C18—H18B	110.2
C10—C8—C7	124.77 (15)	C19—C18—H18B	110.2
N1—C9—C8	107.87 (14)	H18A—C18—H18B	108.5
N1—C9—H9	126.1	C18—C19—H19A	109.5
C8—C9—H9	126.1	C18—C19—H19B	109.5
C11—C10—C8	107.68 (14)	H19A—C19—H19B	109.5
C11—C10—H10	126.2	C18—C19—H19C	109.5
C8—C10—H10	126.2	H19A—C19—H19C	109.5
C10—C11—N1	107.06 (14)	H19B—C19—H19C	109.5
C10—C11—C12	136.21 (15)	C9—N1—C13	128.99 (14)
N1—C11—C12	116.74 (14)	C9—N1—C11	109.44 (14)
C15—C12—C11	121.40 (15)	C13—N1—C11	121.57 (14)
C15—C12—H12	119.3	C17—O3—C18	115.64 (17)

Experimental details

Crystal data
Chemical formula	C₁₉H₁₇NO₃
M_r	307.34
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	8.177 (5), 17.243 (5), 11.191 (5)
β (°)	102.070 (5)
V (Å³)	1543.0 (13)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.18 × 0.15 × 0.14

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2005)
T_min, T_max	0.983, 0.990
No. of measured, independent and observed [I > 2σ(I)] reflections	8583, 3150, 2434
R_int	0.124
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.056, 0.166, 1.04
No. of reflections	3150
No. of parameters	211
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.30, −0.22

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL (Sheldrick, 2008).

Acknowledgements

The author thank Dr Qing Feng Wang, Taishan University, for the data collection.

References

Bruker (2005). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Ge, Y. Q., Hao, B. Q., Duan, G. Y. & Wang, J. W. (2011). J. Lumin. 131, 1070–1076. Web of Science CrossRef CAS Google Scholar
Ge, Y. Q., Jia, J., Li, Y., Yin, L. & Wang, J. W. (2009a). Heterocycles, 78, 197–206. CAS Google Scholar
Ge, Y. Q., Jia, J., Yang, H., Zhao, G. L., Zhan, F. X. & Wang, J. W. (2009b). Heterocycles, 78, 725–736. CAS Google Scholar
Jia, J., Ge, Y. Q., Tao, X. T. & Wang, J. W. (2010). Heterocycles, 81, 185–194. CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar