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ISSN: 2056-9890

Methyl 4-methyl-2-oxo-1,2,5,6-tetra­hydro-4H-pyrrolo[3,2,1-ij]quinoline-6-carboxyl­ate

aSamara State Technical University, Molodogvardeyskay Str. 244, 443100 Samara, Russian Federation, and bDepartment of Chemistry, Moscow State University, 119992 Moscow, Russian Federation
*Correspondence e-mail: rybakov20021@yandex.ru

(Received 10 July 2009; accepted 28 July 2009; online 31 July 2009)

In the title mol­ecule, C14H15NO3, the six-membered heterocyclic ring exhibits an envelope conformation. In the crystal, C—H⋯π inter­actions link the mol­ecules into centrosymmetric dimers, and weak inter­molecular C—H⋯O hydrogen bonds link these dimers into columns propagated along [100].

Related literature

For details of the synthesis, see: Zhuravleva et al. (2009[Zhuravleva, Yu. A., Zimichev, A. V., Zemtsova, M. N. & Klimochkin, Yu. N. (2009). Russ. J. Org. Chem. 45, 622-625.]). For a related structure, see: Bond et al. (1979[Bond, R. F., Boeyens, J. C. A., Holzapfel, C. W. & Steyn, P. S. (1979). J. Chem. Soc. Perkin Trans. 1, pp. 1751-1761.]). For a description of the Cambridge Structural Database, see: Allen (2002[Allen, F. H. (2002). Acta Cryst. B58, 380-388.]).

[Scheme 1]

Experimental

Crystal data
  • C14H15NO3

  • Mr = 245.27

  • Monoclinic, P 21 /c

  • a = 8.309 (3) Å

  • b = 18.524 (5) Å

  • c = 8.730 (3) Å

  • β = 112.30 (3)°

  • V = 1243.2 (8) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.09 mm−1

  • T = 295 K

  • 0.20 × 0.20 × 0.20 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: none

  • 2699 measured reflections

  • 2445 independent reflections

  • 1974 reflections with I > 2σ(I)

  • Rint = 0.030

  • 1 standard reflections frequency: 60 min intensity decay: 2%

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.174

  • S = 1.09

  • 2445 reflections

  • 165 parameters

  • H-atom parameters constrained

  • Δρmax = 0.29 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3ACgi 0.97 2.55 3.514 (3) 174
C4—H4⋯O12ii 0.98 2.40 3.274 (3) 149
C11—H11A⋯O12iii 0.97 2.56 3.394 (3) 145
Symmetry codes: (i) -x, -y+1, -z+1; (ii) x-1, y, z; (iii) -x+1, -y+1, -z+1. Cg is the centroid of the C5–C10 ring.

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994[Enraf-Nonius (1994). CAD-4 EXPRESS. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]).

Supporting information


Comment top

Alkaloids have diverse and impotant physiological activity but it is impossible to fill alkaloids demand from natural source. This causes an attention to new synthetic methods and investigation of similar compounds. Methyl 2-oxo-1,2,5,6-tetrahydro-4H-pyrrolo[3,2,1-ij]quinoline-6-carboxylate (II) was prepared from the previously synthesized substituted 1,2,3,4-tetrahydroquinoline-4-carboxylic acid (I) - Fig. 1. The configuration of substituents cannot be resolved unambiguously by NMR. In accordance with the 1H NMR and GC-MS data starting I was pure cis-isomer (Zhuravleva et al., 2009). Only one entry (Bond et al., 1979) with the same heterothricycllic moiety was found in CSDB (ver. 5.30; Allen, 2002). All geometric parameters - the same bonds and angles are identical in s.u. intervals.

In the crystal, the C–H···π (centroid of C5-10) interactions (Table 1) link the molecules into centrosymmetric dimers. Weak intermolecular C–H···O hydrogen bonds (Table 1) link further these dimers into columns propagated in direction [100] .

Related literature top

For details of the synthesis, see: Zhuravleva et al. (2009). For a related structure, see: Bond et al. (1979). For a description of the Cambridge Structural Database, see: Allen (2002). Cg is the centroid of the C5–C10 ring.

Experimental top

To a stirred solution of cis-methyl 1-(chloroacetyl)-2-methyl-1,2,3,4-tetrahydroquinoline-4-carboxylate (3.6 mmol) in 1,2-dichlorobenzene (20 ml) aluminium chloride (36 mmol) was added dropwise at 378 K. The resulting mixture was stirred for 5 h at 378 K. To the cooled reaction mixture was added ice-water and adjusted to pH 10 with solution of sodium hydrocarbonate. The mixture was extracted with ethyl acetate, dried over anhydrous sodium sulfate and concentrated under reduced pressure. Recrystallization of the crude product from ethanol gave 0.73 g of colourless crystals. Yield 73%, mp 398-341 K.

IR, ν, cm-1: 1731 (CO), 1701 (NCO). MS, m/z: 245 (100) [M]+, 230 (40), 187 (7), 186 (84), 170 (66), 158 (91), 142 (46). 1H NMR, δ: 1.15 d (3H, CH3), 2.09-2.20 m (1H, 3-CH2), 2.30-2.40 m (1H, 3-CH), 3.50 s (1H, CH2), 3.55 s (1H, CH2), 3.65 s (3H, OCH3), 3.96-4.01 m (1H, 2-CH), 4.17-4.27 m (1H, 4-CH), 6.95 t (1H, 6-H), 7.13 pt (2H, 7-H, 5-H). Anal. calc. for C14H15NO3, %: C 69.21; H 6.37; N 5.53. Found, %: C 68.57; H 6.12; N 5.71.

Single crystals for X-ray analysis were obtained by slow evaporation of an methylene chloride - hexane (2: 3) solution. IR spectrum was recorded (in KBr) on Shimadzu FTIR-8400S. Mass spectrum was measured on Finnigan Trance DSQ spectrometer. 1H NMR spectrum was obtained in DMSO-d6 on Bruker AM 300 (300 MHz), using TMS as internal standard. Elemental composition was determined on Euro Vector EA-3000 elemental analyzer.

Refinement top

All H-atoms were geometrically positioned and refined using a riding model with d(C–H) = 0.93 Å, Uiso(H) = 1.2Ueq(C) for aromatic, d(C–H) = 0.97 Å, Uiso(H) = 1.2Ueq(C) for CH2, d(C–H) = 0.96 Å, Uiso(H) = 1.5Ueq(C) for CH3 atoms.

Computing details top

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS (Enraf–Nonius, 1994); data reduction: XCAD4 (Harms & Wocadlo, 1995); 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: WinGX (Farrugia, 1999).

Figures top
[Figure 1] Fig. 1. Synthesis of II.
[Figure 2] Fig. 2. Molecular structure of the title compound II, showing the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. The H atoms are presented as a small spheres of arbitrary radius.
Methyl 4-methyl-2-oxo-1,2,5,6-tetrahydro-4H- pyrrolo[3,2,1-ij]quinoline-6-carboxylate top
Crystal data top
C14H15NO3F(000) = 520
Mr = 245.27Dx = 1.310 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 25 reflections
a = 8.309 (3) Åθ = 19.8–20.5°
b = 18.524 (5) ŵ = 0.09 mm1
c = 8.730 (3) ÅT = 295 K
β = 112.30 (3)°Prism, yellow
V = 1243.2 (8) Å30.20 × 0.20 × 0.20 mm
Z = 4
Data collection top
Enraf–Nonius CAD-4
diffractometer
Rint = 0.030
Radiation source: Fine-focus sealed tubeθmax = 26.0°, θmin = 2.2°
Graphite monochromatorh = 109
Nonprofiled ω scansk = 022
2699 measured reflectionsl = 010
2445 independent reflections1 standard reflections every 60 min
1974 reflections with I > 2σ(I) intensity decay: 2%
Refinement top
Refinement on F2Primary atom site location: Direct
Least-squares matrix: FullSecondary atom site location: Difmap
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: Geom
wR(F2) = 0.174H-atom parameters constrained
S = 1.09 w = 1/[σ2(Fo2) + (0.1046P)2 + 0.277P]
where P = (Fo2 + 2Fc2)/3
2445 reflections(Δ/σ)max = 0.003
165 parametersΔρmax = 0.29 e Å3
0 restraintsΔρmin = 0.33 e Å3
Crystal data top
C14H15NO3V = 1243.2 (8) Å3
Mr = 245.27Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.309 (3) ŵ = 0.09 mm1
b = 18.524 (5) ÅT = 295 K
c = 8.730 (3) Å0.20 × 0.20 × 0.20 mm
β = 112.30 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
Rint = 0.030
2699 measured reflections1 standard reflections every 60 min
2445 independent reflections intensity decay: 2%
1974 reflections with I > 2σ(I)
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.174H-atom parameters constrained
S = 1.09Δρmax = 0.29 e Å3
2445 reflectionsΔρmin = 0.33 e Å3
165 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 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 (Å2) top
xyzUiso*/Ueq
N10.1569 (2)0.42646 (8)0.3299 (2)0.0427 (4)
C20.1249 (3)0.35798 (10)0.3939 (2)0.0465 (5)
H20.22710.34700.49370.056*
C210.1052 (3)0.29783 (11)0.2711 (3)0.0580 (6)
H21A0.00130.30430.17680.087*
H21B0.10270.25220.32230.087*
H21C0.20160.29880.23600.087*
C30.0291 (3)0.36744 (11)0.4463 (2)0.0475 (5)
H3A0.00690.39770.54430.057*
H3B0.06000.32060.47650.057*
C40.1924 (3)0.40114 (11)0.3133 (2)0.0453 (5)
H40.26910.41580.36970.054*
C410.2951 (3)0.34861 (11)0.1782 (3)0.0505 (5)
O410.3534 (3)0.36109 (10)0.0332 (2)0.0836 (6)
O420.3192 (2)0.28667 (8)0.2428 (2)0.0678 (5)
C430.4180 (4)0.23173 (15)0.1274 (4)0.0925 (10)
H43A0.52310.25250.04960.139*
H43B0.44660.19350.18690.139*
H43C0.34990.21280.06910.139*
C50.1448 (2)0.46862 (10)0.2453 (2)0.0407 (4)
C60.2560 (3)0.52609 (12)0.1702 (3)0.0554 (6)
H60.37220.52380.15780.067*
C70.1959 (3)0.58653 (12)0.1140 (3)0.0630 (7)
H70.27270.62390.06420.076*
C80.0246 (3)0.59218 (11)0.1306 (2)0.0557 (6)
H80.01390.63270.09170.067*
C90.0883 (3)0.53697 (10)0.2055 (2)0.0443 (5)
C100.0247 (2)0.47699 (9)0.2586 (2)0.0362 (4)
C110.2786 (3)0.52466 (12)0.2464 (3)0.0558 (6)
H11A0.34850.56080.32330.067*
H11B0.30500.52560.14730.067*
C120.3104 (3)0.45028 (12)0.3248 (3)0.0521 (5)
O120.4456 (2)0.41618 (10)0.3776 (3)0.0769 (6)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N10.0376 (8)0.0402 (9)0.0496 (9)0.0039 (6)0.0159 (7)0.0012 (7)
C20.0446 (10)0.0439 (11)0.0427 (10)0.0043 (8)0.0071 (8)0.0094 (8)
C210.0725 (15)0.0358 (10)0.0690 (14)0.0055 (10)0.0308 (12)0.0003 (9)
C30.0561 (12)0.0499 (11)0.0356 (9)0.0064 (9)0.0164 (8)0.0018 (8)
C40.0408 (10)0.0489 (11)0.0491 (11)0.0034 (8)0.0203 (8)0.0069 (8)
C410.0396 (10)0.0497 (12)0.0563 (13)0.0070 (8)0.0115 (9)0.0031 (9)
O410.0950 (14)0.0728 (12)0.0569 (11)0.0272 (10)0.0007 (9)0.0017 (9)
O420.0704 (11)0.0501 (9)0.0745 (11)0.0186 (8)0.0183 (9)0.0025 (8)
C430.0841 (19)0.0559 (15)0.111 (2)0.0299 (14)0.0071 (17)0.0089 (15)
C50.0384 (9)0.0415 (10)0.0374 (9)0.0009 (7)0.0090 (7)0.0070 (7)
C60.0436 (11)0.0502 (12)0.0577 (13)0.0093 (9)0.0026 (9)0.0108 (10)
C70.0725 (16)0.0412 (11)0.0519 (13)0.0150 (10)0.0029 (11)0.0007 (9)
C80.0873 (17)0.0346 (10)0.0378 (10)0.0015 (10)0.0154 (10)0.0016 (8)
C90.0595 (12)0.0382 (10)0.0371 (9)0.0051 (8)0.0203 (9)0.0064 (7)
C100.0413 (10)0.0335 (9)0.0320 (8)0.0013 (7)0.0119 (7)0.0033 (7)
C110.0624 (14)0.0507 (12)0.0648 (13)0.0134 (10)0.0358 (11)0.0086 (10)
C120.0427 (11)0.0525 (12)0.0652 (13)0.0049 (9)0.0251 (10)0.0103 (10)
O120.0426 (9)0.0747 (12)0.1144 (15)0.0075 (8)0.0308 (9)0.0048 (10)
Geometric parameters (Å, º) top
N1—C121.366 (3)C43—H43A0.9600
N1—C101.397 (2)C43—H43B0.9600
N1—C21.451 (2)C43—H43C0.9600
C2—C211.512 (3)C5—C101.377 (3)
C2—C31.523 (3)C5—C61.399 (3)
C2—H20.9800C6—C71.389 (4)
C21—H21A0.9600C6—H60.9300
C21—H21B0.9600C7—C81.379 (4)
C21—H21C0.9600C7—H70.9300
C3—C41.544 (3)C8—C91.374 (3)
C3—H3A0.9700C8—H80.9300
C3—H3B0.9700C9—C101.383 (3)
C4—C51.500 (3)C9—C111.501 (3)
C4—C411.517 (3)C11—C121.517 (3)
C4—H40.9800C11—H11A0.9700
C41—O411.193 (3)C11—H11B0.9700
C41—O421.327 (3)C12—O121.217 (3)
O42—C431.449 (3)
C12—N1—C10110.78 (17)O42—C43—H43B109.5
C12—N1—C2127.21 (17)H43A—C43—H43B109.5
C10—N1—C2121.98 (16)O42—C43—H43C109.5
N1—C2—C21110.93 (17)H43A—C43—H43C109.5
N1—C2—C3108.22 (16)H43B—C43—H43C109.5
C21—C2—C3114.86 (18)C10—C5—C6115.24 (19)
N1—C2—H2107.5C10—C5—C4118.39 (16)
C21—C2—H2107.5C6—C5—C4126.37 (19)
C3—C2—H2107.5C7—C6—C5121.1 (2)
C2—C21—H21A109.5C7—C6—H6119.4
C2—C21—H21B109.5C5—C6—H6119.4
H21A—C21—H21B109.5C8—C7—C6121.3 (2)
C2—C21—H21C109.5C8—C7—H7119.4
H21A—C21—H21C109.5C6—C7—H7119.4
H21B—C21—H21C109.5C9—C8—C7119.0 (2)
C2—C3—C4114.81 (16)C9—C8—H8120.5
C2—C3—H3A108.6C7—C8—H8120.5
C4—C3—H3A108.6C8—C9—C10118.6 (2)
C2—C3—H3B108.6C8—C9—C11133.9 (2)
C4—C3—H3B108.6C10—C9—C11107.45 (17)
H3A—C3—H3B107.5C5—C10—C9124.77 (17)
C5—C4—C41112.46 (17)C5—C10—N1124.60 (17)
C5—C4—C3110.24 (15)C9—C10—N1110.62 (17)
C41—C4—C3113.57 (17)C9—C11—C12103.46 (16)
C5—C4—H4106.7C9—C11—H11A111.1
C41—C4—H4106.7C12—C11—H11A111.1
C3—C4—H4106.7C9—C11—H11B111.1
O41—C41—O42123.5 (2)C12—C11—H11B111.1
O41—C41—C4125.6 (2)H11A—C11—H11B109.0
O42—C41—C4110.80 (19)O12—C12—N1124.0 (2)
C41—O42—C43116.7 (2)O12—C12—C11128.3 (2)
O42—C43—H43A109.5N1—C12—C11107.66 (18)
C12—N1—C2—C2178.4 (3)C7—C8—C9—C101.3 (3)
C10—N1—C2—C2199.7 (2)C7—C8—C9—C11179.1 (2)
C12—N1—C2—C3154.76 (19)C6—C5—C10—C90.7 (3)
C10—N1—C2—C327.2 (2)C4—C5—C10—C9178.29 (17)
N1—C2—C3—C451.5 (2)C6—C5—C10—N1179.68 (17)
C21—C2—C3—C473.1 (2)C4—C5—C10—N10.7 (3)
C2—C3—C4—C550.2 (2)C8—C9—C10—C51.4 (3)
C2—C3—C4—C4177.1 (2)C11—C9—C10—C5178.81 (17)
C5—C4—C41—O419.3 (3)C8—C9—C10—N1179.47 (16)
C3—C4—C41—O41135.4 (3)C11—C9—C10—N10.3 (2)
C5—C4—C41—O42173.46 (17)C12—N1—C10—C5179.89 (17)
C3—C4—C41—O4247.4 (2)C2—N1—C10—C51.8 (3)
O41—C41—O42—C431.8 (4)C12—N1—C10—C90.8 (2)
C4—C41—O42—C43179.1 (2)C2—N1—C10—C9179.16 (16)
C41—C4—C5—C10105.06 (19)C8—C9—C11—C12178.6 (2)
C3—C4—C5—C1022.8 (2)C10—C9—C11—C121.1 (2)
C41—C4—C5—C676.1 (2)C10—N1—C12—O12179.4 (2)
C3—C4—C5—C6156.10 (19)C2—N1—C12—O121.1 (4)
C10—C5—C6—C70.1 (3)C10—N1—C12—C111.5 (2)
C4—C5—C6—C7179.04 (19)C2—N1—C12—C11179.75 (18)
C5—C6—C7—C80.2 (3)C9—C11—C12—O12179.4 (2)
C6—C7—C8—C90.5 (3)C9—C11—C12—N11.6 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cgi0.972.553.514 (3)174
C4—H4···O12ii0.982.403.274 (3)149
C11—H11A···O12iii0.972.563.394 (3)145
Symmetry codes: (i) x, y+1, z+1; (ii) x1, y, z; (iii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC14H15NO3
Mr245.27
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)8.309 (3), 18.524 (5), 8.730 (3)
β (°) 112.30 (3)
V3)1243.2 (8)
Z4
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.20 × 0.20 × 0.20
Data collection
DiffractometerEnraf–Nonius CAD-4
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
2699, 2445, 1974
Rint0.030
(sin θ/λ)max1)0.617
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.174, 1.09
No. of reflections2445
No. of parameters165
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.29, 0.33

Computer programs: CAD-4 EXPRESS (Enraf–Nonius, 1994), XCAD4 (Harms & Wocadlo, 1995), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cgi0.9702.5473.514 (3)174
C4—H4···O12ii0.9802.3983.274 (3)149
C11—H11A···O12iii0.9702.5573.394 (3)145
Symmetry codes: (i) x, y+1, z+1; (ii) x1, y, z; (iii) x+1, y+1, z+1.
 

Acknowledgements

The authors are indebted to the Russian Foundation for Basic Research for covering the licence fee for use of the Cambridge Structural Database.

References

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