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ISSN: 2056-9890

Phen­yl(pyrrolo[2,1-a]isoquinolin-3-yl)methanone

aInstitute of Chemistry and Chemical Engineering, Xuzhou Normal University, Xuzhou 221116, People's Republic of China, and bKey Laboratory of Biotechnology for Medical Plants of Jiangsu Province, Xuzhou Normal University, Xuzhou, Jiangsu 221116, People's Republic of China
*Correspondence e-mail: liu_yun3@sina.com.cn

(Received 9 April 2010; accepted 10 May 2010; online 19 May 2010)

In the title compound, C19H13NO, the fused isoquinoline–pyrrole system is planar (r.m.s. deviation = 0.0249] Å) and makes a dihedral angle of 53.73 (9)° with the phenyl ring. An intra­molecular C—H⋯O inter­action generates an S(6) ring motif.

Related literature

For the biological activity of indolizine, see: Olden et al. (1991[Olden, K., Breton, P., Grzegorzevski, K., Yasuda, Y., Gause, B. L., Creaipe, O. A., Newton, S. A. & White, S. L. (1991). Pharmacol. Ther. 50, 285-290.]); Jaffrezou et al. (1992[Jaffrezou, J. P., Levade, T., Thurneyssen, O., Chiron, M., Bordier, C., Attal, M., Chatelain, P. & Laurent, G. (1992). Cancer Res. 52, 1352-1359.]). For our work on the direct one-pot syntheses of pyrrolo[2,1-a]isoquinolines, see: Liu et al. (2010[Liu, Y., Zhang, Y., Shen, Y.-M., Hu, H.-W. & Xu, J.-H. (2010). Org. Biomol. Chem. doi:10.1039/c000277a.]). For the preparation of pyrrolo[2,1-a]isoquinoline, see: Verna et al. (2009[Verna, A. K., Kesharwani, T., Singh, J., Tandon, V. & Larock, R. C. (2009). Angew. Chem. Int. Ed. 48, 1138-1143.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C19H13NO

  • Mr = 271.30

  • Monoclinic, P 21 /c

  • a = 28.637 (6) Å

  • b = 4.0400 (8) Å

  • c = 11.824 (2) Å

  • β = 101.02 (3)°

  • V = 1342.7 (5) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 295 K

  • 0.30 × 0.20 × 0.10 mm

Data collection
  • Enraf–Nonius CAD-4 diffractometer

  • Absorption correction: ψ scan (XCAD4; Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]) Tmin = 0.976, Tmax = 0.992

  • 2351 measured reflections

  • 2351 independent reflections

  • 1388 reflections with I > 2σ(I)

  • 3 standard reflections every 200 reflections intensity decay: none

Refinement
  • R[F2 > 2σ(F2)] = 0.072

  • wR(F2) = 0.139

  • S = 1.00

  • 2351 reflections

  • 190 parameters

  • H-atom parameters constrained

  • Δρmax = 0.23 e Å−3

  • Δρmin = −0.30 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C19—H19A⋯O 0.93 2.31 2.875 (4) 119

Data collection: CAD-4 Software (Enraf–Nonius, 1989[Enraf-Nonius (1989). CAD-4 Software. Enraf-Nonius, Delft, The Netherlands.]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995[Harms, K. & Wocadlo, S. (1995). XCAD4. University of Marburg, Germany.]); program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

The natural and many synthetic indolizines have a diversity of biological activity and are playing an increasingly important role in developing new pharmaceuticals [Olden et al., 1991; Jaffrezou et al., 1992]. Pyrrolo[2,1-a]- isoquinolines are 7,8- benzo- fused indolizines and occur in several marine alkaloids. The synthesis of these structures is drawing much recent research interest [Verna et al., 2009]. In our research work on the direct one pot syntheses of pyrrolo[2,1-a]isoquinolines [Liu et al., 2010], we have prepared the title compound, (I), as one of the products. As part of this study, we have undertaken an X-ray crystallographic analysis of (I) in order to confirm its structure. The bond lengths and angles of the title molecule (Fig. 1) are within normal ranges (Allen et al., 1987). he fused isoquinoline-pyrrole moiety is planar. The dihedral angle between the isoquinoline-pyrrole fused ring and benzene ring is 53.73 (9)°. Although atoms C8, C11 and C19 attached to atom N are all of sp2 hybridization, their different environments cause slight differences in the N—C8, N—C11 and N—C19 bond lengths, and in the C19— N—C11, C19— N—C8 , C11—N—C8 and C10—C11—N angles (Table 1). An intramolecular C—H···O weak hydrogen bond generating an S(6) ring is observed (Table 2). The crystal packing is stabilized by van der Waals forces.

Related literature top

For the biological activity of indolizine, see: Olden et al. (1991); Jaffrezou et al. (1992). For the preparation of pyrrolo[2,1-a]isoquinoline, see: Verna et al. (2009). For our work on the direct one-pot syntheses of pyrrolo[2,1-a]isoquinolines, see: Liu et al. (2010). For bond-length data, see: Allen et al. (1987);

Experimental top

The compound (I) was prepared by the reaction of DMF solution of 2-(2-oxo-2- phenylethyl)isoquinolinium bromide with an excess amount of maleic acid in the presence of TPCD and potassium carbonate. After the reaction was completed, the mixture was isolated by chromatography on a silica gel column after evaporation of the solvent. Single crystals of (I) were obtained by slow evaporation from an petroleum ether-ethyl acetate(3:1) solvent system (yield 80%).

Refinement top

The H atoms were geometrically placed and were treated as riding, with C—H = 0.93Å .

Structure description top

The natural and many synthetic indolizines have a diversity of biological activity and are playing an increasingly important role in developing new pharmaceuticals [Olden et al., 1991; Jaffrezou et al., 1992]. Pyrrolo[2,1-a]- isoquinolines are 7,8- benzo- fused indolizines and occur in several marine alkaloids. The synthesis of these structures is drawing much recent research interest [Verna et al., 2009]. In our research work on the direct one pot syntheses of pyrrolo[2,1-a]isoquinolines [Liu et al., 2010], we have prepared the title compound, (I), as one of the products. As part of this study, we have undertaken an X-ray crystallographic analysis of (I) in order to confirm its structure. The bond lengths and angles of the title molecule (Fig. 1) are within normal ranges (Allen et al., 1987). he fused isoquinoline-pyrrole moiety is planar. The dihedral angle between the isoquinoline-pyrrole fused ring and benzene ring is 53.73 (9)°. Although atoms C8, C11 and C19 attached to atom N are all of sp2 hybridization, their different environments cause slight differences in the N—C8, N—C11 and N—C19 bond lengths, and in the C19— N—C11, C19— N—C8 , C11—N—C8 and C10—C11—N angles (Table 1). An intramolecular C—H···O weak hydrogen bond generating an S(6) ring is observed (Table 2). The crystal packing is stabilized by van der Waals forces.

For the biological activity of indolizine, see: Olden et al. (1991); Jaffrezou et al. (1992). For the preparation of pyrrolo[2,1-a]isoquinoline, see: Verna et al. (2009). For our work on the direct one-pot syntheses of pyrrolo[2,1-a]isoquinolines, see: Liu et al. (2010). For bond-length data, see: Allen et al. (1987);

Computing details top

Data collection: CAD-4 Software (Enraf–Nonius, 1989); cell refinement: CAD-4 Software (Enraf–Nonius, 1989); data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I), with atom labels and 50% probability displacement ellipsoids for non-H atoms.
Phenyl(pyrrolo[2,1-a]isoquinolin-3-yl)methanone top
Crystal data top
C19H13NOF(000) = 568
Mr = 271.30Dx = 1.342 Mg m3
Monoclinic, P21/cMelting point: 413 K
Hall symbol: -P 2ybcMo Kα radiation, λ = 0.71073 Å
a = 28.637 (6) ÅCell parameters from 25 reflections
b = 4.0400 (8) Åθ = 9–12°
c = 11.824 (2) ŵ = 0.08 mm1
β = 101.02 (3)°T = 295 K
V = 1342.7 (5) Å3Block, colourless
Z = 40.30 × 0.20 × 0.10 mm
Data collection top
Enraf–Nonius CAD-4
diffractometer
1388 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.000
Graphite monochromatorθmax = 25.0°, θmin = 1.5°
ω/2θ scansh = 3433
Absorption correction: ψ scan
(XCAD4; Harms & Wocadlo, 1995)
k = 04
Tmin = 0.976, Tmax = 0.992l = 014
2351 measured reflections3 standard reflections every 200 reflections
2351 independent reflections intensity decay: none
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.072H-atom parameters constrained
wR(F2) = 0.139 w = 1/[σ2(Fo2) + (0.015P)2 + 2.250P]
where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max < 0.001
2351 reflectionsΔρmax = 0.23 e Å3
190 parametersΔρmin = 0.30 e Å3
0 restraintsAbsolute structure: (XCAD4; Harms & Wocadlo, 1995)
Primary atom site location: structure-invariant direct methods
Crystal data top
C19H13NOV = 1342.7 (5) Å3
Mr = 271.30Z = 4
Monoclinic, P21/cMo Kα radiation
a = 28.637 (6) ŵ = 0.08 mm1
b = 4.0400 (8) ÅT = 295 K
c = 11.824 (2) Å0.30 × 0.20 × 0.10 mm
β = 101.02 (3)°
Data collection top
Enraf–Nonius CAD-4
diffractometer
1388 reflections with I > 2σ(I)
Absorption correction: ψ scan
(XCAD4; Harms & Wocadlo, 1995)
Rint = 0.000
Tmin = 0.976, Tmax = 0.9923 standard reflections every 200 reflections
2351 measured reflections intensity decay: none
2351 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0720 restraints
wR(F2) = 0.139H-atom parameters constrained
S = 1.00Δρmax = 0.23 e Å3
2351 reflectionsΔρmin = 0.30 e Å3
190 parametersAbsolute structure: (XCAD4; Harms & Wocadlo, 1995)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
xyzUiso*/Ueq
N0.22455 (9)0.5534 (7)0.9319 (2)0.0382 (7)
C110.19331 (11)0.4146 (9)0.9955 (3)0.0402 (9)
C70.31218 (12)0.5686 (10)0.9370 (3)0.0485 (10)
O0.30873 (9)0.6625 (9)0.8377 (2)0.0725 (10)
C120.14286 (12)0.4449 (10)0.9532 (3)0.0447 (9)
C30.36071 (11)0.5108 (10)1.0092 (3)0.0453 (9)
C80.27112 (11)0.4828 (9)0.9873 (3)0.0402 (9)
C190.20843 (12)0.7328 (10)0.8334 (3)0.0461 (9)
H19A0.23020.83090.79470.055*
C180.16185 (12)0.7680 (10)0.7927 (3)0.0513 (10)
H18A0.15170.89290.72650.062*
C20.37259 (12)0.6034 (10)1.1233 (3)0.0521 (10)
H2A0.34960.69351.16000.062*
C170.12699 (12)0.6158 (10)0.8496 (3)0.0483 (10)
C90.26796 (12)0.3050 (10)1.0848 (3)0.0458 (9)
H9A0.29360.22841.13890.055*
C100.22029 (12)0.2579 (10)1.0897 (3)0.0477 (10)
H10A0.20860.14161.14620.057*
C130.10950 (12)0.3043 (10)1.0117 (3)0.0528 (10)
H13A0.11970.18781.07980.063*
C140.06138 (14)0.3388 (13)0.9681 (4)0.0706 (14)
H14A0.03930.24981.00800.085*
C160.07802 (13)0.6403 (12)0.8072 (3)0.0628 (12)
H16A0.06720.75090.73820.075*
C60.45267 (14)0.4265 (12)1.1284 (4)0.0711 (13)
H6A0.48370.39901.16840.085*
C150.04577 (15)0.5046 (13)0.8655 (4)0.0711 (14)
H15A0.01340.52380.83610.085*
C40.39519 (13)0.3782 (11)0.9543 (3)0.0567 (11)
H4A0.38750.32070.87690.068*
C50.44071 (14)0.3323 (12)1.0152 (4)0.0684 (13)
H5A0.46350.23650.97920.082*
C10.41862 (13)0.5626 (12)1.1833 (3)0.0650 (12)
H1A0.42670.62631.26020.078*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N0.0359 (15)0.0496 (19)0.0307 (13)0.0024 (15)0.0101 (11)0.0003 (15)
C110.0396 (19)0.048 (2)0.0360 (17)0.0023 (18)0.0148 (15)0.0037 (18)
C70.046 (2)0.064 (3)0.0387 (18)0.013 (2)0.0169 (16)0.007 (2)
O0.0555 (17)0.117 (3)0.0500 (15)0.0072 (19)0.0227 (13)0.0212 (19)
C120.0393 (19)0.050 (2)0.047 (2)0.0018 (19)0.0148 (16)0.013 (2)
C30.0328 (18)0.058 (3)0.049 (2)0.0002 (19)0.0162 (16)0.007 (2)
C80.0398 (19)0.050 (2)0.0334 (17)0.0048 (18)0.0122 (14)0.0029 (18)
C190.051 (2)0.057 (3)0.0318 (17)0.006 (2)0.0117 (15)0.0012 (19)
C180.049 (2)0.064 (3)0.0399 (19)0.017 (2)0.0073 (16)0.009 (2)
C20.043 (2)0.062 (3)0.054 (2)0.002 (2)0.0160 (17)0.000 (2)
C170.0379 (19)0.061 (3)0.046 (2)0.008 (2)0.0071 (15)0.010 (2)
C90.0394 (19)0.060 (3)0.0387 (18)0.008 (2)0.0095 (15)0.0068 (19)
C100.045 (2)0.061 (3)0.0396 (18)0.007 (2)0.0161 (15)0.006 (2)
C130.046 (2)0.057 (3)0.059 (2)0.008 (2)0.0191 (18)0.010 (2)
C140.041 (2)0.091 (4)0.085 (3)0.015 (3)0.026 (2)0.028 (3)
C160.046 (2)0.075 (3)0.064 (2)0.012 (2)0.0013 (19)0.008 (3)
C60.040 (2)0.082 (4)0.090 (3)0.004 (2)0.008 (2)0.022 (3)
C150.042 (2)0.083 (4)0.086 (3)0.003 (3)0.007 (2)0.027 (3)
C40.046 (2)0.064 (3)0.066 (2)0.003 (2)0.0244 (19)0.002 (2)
C50.048 (2)0.068 (3)0.097 (3)0.006 (2)0.033 (2)0.005 (3)
C10.048 (2)0.085 (3)0.060 (2)0.012 (3)0.0059 (19)0.003 (3)
Geometric parameters (Å, º) top
N—C191.374 (4)C17—C161.399 (5)
N—C111.392 (4)C9—C101.390 (4)
N—C81.399 (4)C9—H9A0.9300
C11—C101.382 (5)C10—H10A0.9300
C11—C121.441 (4)C13—C141.383 (5)
C7—O1.220 (4)C13—H13A0.9300
C7—C81.458 (4)C14—C151.383 (6)
C7—C31.504 (5)C14—H14A0.9300
C12—C131.402 (5)C16—C151.368 (6)
C12—C171.404 (5)C16—H16A0.9300
C3—C21.379 (5)C6—C51.371 (5)
C3—C41.388 (4)C6—C11.385 (5)
C8—C91.376 (4)C6—H6A0.9300
C19—C181.336 (4)C15—H15A0.9300
C19—H19A0.9300C4—C51.376 (5)
C18—C171.444 (5)C4—H4A0.9300
C18—H18A0.9300C5—H5A0.9300
C2—C11.382 (5)C1—H1A0.9300
C2—H2A0.9300
C19—N—C11121.6 (3)C8—C9—C10109.2 (3)
C19—N—C8129.8 (3)C8—C9—H9A125.4
C11—N—C8108.5 (3)C10—C9—H9A125.4
C10—C11—N107.6 (3)C11—C10—C9107.8 (3)
C10—C11—C12133.4 (3)C11—C10—H10A126.1
N—C11—C12118.9 (3)C9—C10—H10A126.1
O—C7—C8123.0 (3)C14—C13—C12120.0 (4)
O—C7—C3119.4 (3)C14—C13—H13A120.0
C8—C7—C3117.4 (3)C12—C13—H13A120.0
C13—C12—C17119.5 (3)C13—C14—C15120.5 (4)
C13—C12—C11121.8 (3)C13—C14—H14A119.7
C17—C12—C11118.7 (3)C15—C14—H14A119.7
C2—C3—C4119.8 (3)C15—C16—C17121.2 (4)
C2—C3—C7122.8 (3)C15—C16—H16A119.4
C4—C3—C7117.2 (3)C17—C16—H16A119.4
C9—C8—N106.9 (3)C5—C6—C1120.1 (4)
C9—C8—C7130.8 (3)C5—C6—H6A119.9
N—C8—C7122.1 (3)C1—C6—H6A119.9
C18—C19—N120.8 (3)C16—C15—C14120.0 (4)
C18—C19—H19A119.6C16—C15—H15A120.0
N—C19—H19A119.6C14—C15—H15A120.0
C19—C18—C17121.2 (3)C5—C4—C3119.7 (4)
C19—C18—H18A119.4C5—C4—H4A120.2
C17—C18—H18A119.4C3—C4—H4A120.2
C3—C2—C1120.2 (4)C6—C5—C4120.5 (4)
C3—C2—H2A119.9C6—C5—H5A119.7
C1—C2—H2A119.9C4—C5—H5A119.7
C16—C17—C12118.8 (4)C6—C1—C2119.6 (4)
C16—C17—C18122.5 (4)C6—C1—H1A120.2
C12—C17—C18118.6 (3)C2—C1—H1A120.2
C19—N—C11—C10178.7 (3)C13—C12—C17—C160.1 (6)
C8—N—C11—C100.2 (4)C11—C12—C17—C16178.8 (4)
C19—N—C11—C123.5 (5)C13—C12—C17—C18178.0 (4)
C8—N—C11—C12178.0 (3)C11—C12—C17—C183.0 (5)
C10—C11—C12—C131.4 (7)C19—C18—C17—C16178.2 (4)
N—C11—C12—C13178.5 (3)C19—C18—C17—C123.8 (6)
C10—C11—C12—C17177.5 (4)N—C8—C9—C101.2 (4)
N—C11—C12—C170.4 (5)C7—C8—C9—C10173.2 (4)
O—C7—C3—C2138.8 (4)N—C11—C10—C90.9 (4)
C8—C7—C3—C246.0 (6)C12—C11—C10—C9178.2 (4)
O—C7—C3—C436.8 (6)C8—C9—C10—C111.3 (5)
C8—C7—C3—C4138.3 (4)C17—C12—C13—C141.0 (6)
C19—N—C8—C9177.8 (3)C11—C12—C13—C14179.9 (4)
C11—N—C8—C90.6 (4)C12—C13—C14—C151.6 (7)
C19—N—C8—C77.2 (6)C12—C17—C16—C150.7 (6)
C11—N—C8—C7174.4 (3)C18—C17—C16—C15177.3 (4)
O—C7—C8—C9162.9 (4)C17—C16—C15—C140.2 (7)
C3—C7—C8—C912.1 (6)C13—C14—C15—C161.0 (7)
O—C7—C8—N10.8 (6)C2—C3—C4—C51.7 (6)
C3—C7—C8—N174.2 (3)C7—C3—C4—C5177.5 (4)
C11—N—C19—C182.9 (5)C1—C6—C5—C41.4 (7)
C8—N—C19—C18178.9 (4)C3—C4—C5—C62.2 (7)
N—C19—C18—C170.8 (6)C5—C6—C1—C20.1 (7)
C4—C3—C2—C10.4 (6)C3—C2—C1—C60.4 (7)
C7—C3—C2—C1175.9 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C19—H19A···O0.932.312.875 (4)119

Experimental details

Crystal data
Chemical formulaC19H13NO
Mr271.30
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)28.637 (6), 4.0400 (8), 11.824 (2)
β (°) 101.02 (3)
V3)1342.7 (5)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.30 × 0.20 × 0.10
Data collection
DiffractometerEnraf–Nonius CAD-4
Absorption correctionψ scan
(XCAD4; Harms & Wocadlo, 1995)
Tmin, Tmax0.976, 0.992
No. of measured, independent and
observed [I > 2σ(I)] reflections
2351, 2351, 1388
Rint0.000
(sin θ/λ)max1)0.595
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.072, 0.139, 1.00
No. of reflections2351
No. of parameters190
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.23, 0.30
Absolute structure(XCAD4; Harms & Wocadlo, 1995)

Computer programs: CAD-4 Software (Enraf–Nonius, 1989), XCAD4 (Harms & Wocadlo, 1995), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Selected geometric parameters (Å, º) top
N—C191.374 (4)C7—O1.220 (4)
N—C111.392 (4)C7—C81.458 (4)
N—C81.399 (4)
C19—N—C11121.6 (3)C10—C11—N107.6 (3)
C19—N—C8129.8 (3)O—C7—C8123.0 (3)
C11—N—C8108.5 (3)O—C7—C3119.4 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C19—H19A···O0.932.312.875 (4)119
 

Acknowledgements

The authors thank Xuzhou Normal University (08XLR07) for financial support. This work was also sponsored by the Qing Lan Project (08QLT001).

References

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