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ISSN: 2056-9890

6-(4-Meth­­oxy­phen­yl)-7-phenyl-2,3-di­hydro-1H-pyrrolizine-5-carbaldehyde

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 8 August 2011; accepted 15 August 2011; online 27 August 2011)

The 4-meth­oxy­phenyl residue in the title compound, C21H19NO2, is oriented at a dihedral angle of 54.6 (5)° with respect to the phenyl ring and at a dihedral angle of 52.5 (8)° with respect to the pyrrole ring of the pyrrolizine system. The phenyl ring is oriented at a dihedral angle of 36.2 (5)° with respect to the pyrrole ring. The meth­oxy group makes a C—C—O—C torsion angle of 3.8 (9)° with the attached benzene ring.

Related literature

For the biological activity of aryl­pyrrolizines as mPGES-1 inhibitors, see: Liedtke et al. (2009[Liedtke, A. J., Keck, P. R. W. E. F., Lehmann, F., Koeberle, A., Werz, O. & Laufer, S. (2009). J. Med. Chem. 52, 4968-4972.]). For dual COX/5-LOX inhibitors, see: Laufer (2001[Laufer, S. (2001). Inflammopharmacology, 9, 101-112.]); Tries & Laufer (2001[Tries, S. & Laufer, S. (2001). Inflammopharmacology, 9, 113-124.]).

[Scheme 1]

Experimental

Crystal data
  • C21H19NO2

  • Mr = 317.37

  • Monoclinic, P 21 /n

  • a = 12.2276 (17) Å

  • b = 9.1557 (10) Å

  • c = 15.462 (2) Å

  • β = 104.174 (11)°

  • V = 1678.3 (4) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 193 K

  • 0.30 × 0.20 × 0.07 mm

Data collection
  • Stoe IPDS 2T diffractometer

  • 23718 measured reflections

  • 4043 independent reflections

  • 2868 reflections with I > 2σ(I)

  • Rint = 0.067

Refinement
  • R[F2 > 2σ(F2)] = 0.039

  • wR(F2) = 0.102

  • S = 1.02

  • 4043 reflections

  • 218 parameters

  • H-atom parameters constrained

  • Δρmax = 0.17 e Å−3

  • Δρmin = −0.16 e Å−3

Data collection: X-AREA (Stoe & Cie, 2010)[Stoe & Cie (2010). X-AREA and X-RED. Stoe & Cie GmbH, Darmstadt, Germany.]; cell refinement: X-AREA[Stoe & Cie (2010). X-AREA and X-RED. Stoe & Cie GmbH, Darmstadt, Germany.]; data reduction: X-RED (Stoe & Cie, 2010)[Stoe & Cie (2010). X-AREA and X-RED. Stoe & Cie GmbH, Darmstadt, Germany.]; program(s) used to solve structure: SIR97 (Altomare et al., 1999[Altomare, A., Burla, M. C., Camalli, M., Cascarano, G. L., Giacovazzo, C., Guagliardi, A., Moliterni, A. G. G., Polidori, G. & Spagna, R. (1999). J. Appl. Cryst. 32, 115-119.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: PLATON.

Supporting information


Comment top

Based on ML3000 (Tries & Laufer, 2001 and Laufer, 2001) as dual COX/5-LOX inhibitor, we synthesized and evaluated inhibitors for the microsomal prostaglandin E2 synthase-1 (mPGES-1) (Liedtke et al., 2009). The title compound was synthesized to obtain a template with a reactive group in position 5 of the pyrrolizine moiety which lead to series of differend derivates of the arylpyrrolizine scaffold.

Towards the unsaturated and planar part of the pyrrolizine residue the 4-methoxyphenyl residue is oriented at a dihedral angle of 52.5 (8)° and the plain phenyl ring is oriented at a dihedral angle of 36.2 (5)°. The two phenyl rings are oriented at a dihedral angle of 54.6 (5)° and both centromers show a distance of 4.89 (7) Å. The distance between the para C atoms of the rings (C13, C21) is 6.55 (9) Å. The methoxy group shows a torsion angle of 3.8 (9)° towards the phenyl ring.

Related literature top

For the biological activity of arylpyrrolizines as mPGES-1 inhibitors, see: Liedtke et al. (2009). For dual COX/5-LOX inhibitors, see: Laufer (2001); Tries & Laufer (2001).

Experimental top

The compound was prepared by Vilsmeyer reaction. Phosphoryl chloride (0.484 ml, 5.31 mmol) is added dropwise to ice-cooled solution of 1.18 ml dimethylformamide and 6-(4-methoxyphenyl)-7-phenyl-2,3-dihydro-1H-pyrrolizine (1.5 g, 5.11 mmol); the temperature is kept under 293 K during the addition. Then the mixture is stirred for 1 h at room temperature. Finally the mixture is heated to 333 K for 1 h. The mixture was cooled to 273 K, quenched by water and adjusted to pH 6 with aqueous sodium hydroxide solution 10%.

The product was collected as precipitated solid by filtration, was dissolved in dichloromethane and washed with water three times and finally dried over anhydrous sodium sulfate. The product was concentrated under vacuum. The residue was purified by column chromatography (SiO2, n-hexane / ethyl acetate: 2 + 1). Crystals of the title compound were obtained by slow evaporation of ethanol at room temperature.

Refinement top

Hydrogen atoms attached to carbons were placed at calculated positions with C—H = 0.95 Å (aromatic) or 0.99–1.00 Å (sp3 C-atom). All H atoms were refined with isotropic displacement parameters (set at 1.2–1.5 times of the Ueq of the parent atom).

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
[Figure 1] Fig. 1. View of compound (I). Displacement ellipsoids are drawn at the 50% probability level.
6-(4-Methoxyphenyl)-7-phenyl-2,3-dihydro-1H-pyrrolizine-5-carbaldehyde top
Crystal data top
C21H19NO2F(000) = 672
Mr = 317.37Dx = 1.256 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 18580 reflections
a = 12.2276 (17) Åθ = 2.4–30°
b = 9.1557 (10) ŵ = 0.08 mm1
c = 15.462 (2) ÅT = 193 K
β = 104.174 (11)°Plate, light brown
V = 1678.3 (4) Å30.30 × 0.20 × 0.07 mm
Z = 4
Data collection top
Stoe IPDS 2T
diffractometer
2868 reflections with I > 2σ(I)
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focusRint = 0.067
Detector resolution: 6.67 pixels mm-1θmax = 28.0°, θmin = 2.4°
rotation method scansh = 1615
23718 measured reflectionsk = 1212
4043 independent reflectionsl = 2020
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.102H-atom parameters constrained
S = 1.02 w = 1/[σ2(Fo2) + (0.047P)2 + 0.1927P]
where P = (Fo2 + 2Fc2)/3
4043 reflections(Δ/σ)max < 0.001
218 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = 0.16 e Å3
Crystal data top
C21H19NO2V = 1678.3 (4) Å3
Mr = 317.37Z = 4
Monoclinic, P21/nMo Kα radiation
a = 12.2276 (17) ŵ = 0.08 mm1
b = 9.1557 (10) ÅT = 193 K
c = 15.462 (2) Å0.30 × 0.20 × 0.07 mm
β = 104.174 (11)°
Data collection top
Stoe IPDS 2T
diffractometer
2868 reflections with I > 2σ(I)
23718 measured reflectionsRint = 0.067
4043 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0390 restraints
wR(F2) = 0.102H-atom parameters constrained
S = 1.02Δρmax = 0.17 e Å3
4043 reflectionsΔρmin = 0.16 e Å3
218 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
xyzUiso*/Ueq
C10.06152 (12)0.14978 (15)0.66247 (9)0.0393 (3)
H1A0.09460.22380.70810.047*
H1B0.11080.06250.67090.047*
C20.05958 (14)0.10999 (18)0.66633 (10)0.0517 (4)
H2A0.05990.01710.69910.062*
H2B0.09170.18770.69720.062*
C30.12865 (12)0.09433 (16)0.56986 (10)0.0432 (3)
H3A0.13540.00920.55080.052*
H3B0.20500.13680.56170.052*
N40.06033 (9)0.17804 (11)0.52170 (7)0.0359 (2)
C50.07535 (10)0.22928 (14)0.43583 (9)0.0352 (3)
C60.02545 (10)0.29896 (13)0.43203 (8)0.0319 (3)
C70.10129 (10)0.28749 (13)0.51738 (8)0.0319 (3)
C7A0.04412 (10)0.21009 (13)0.57039 (8)0.0339 (3)
C80.17589 (11)0.20663 (15)0.36689 (10)0.0430 (3)
H80.17760.24500.30950.052*
O90.25971 (9)0.14180 (13)0.37601 (8)0.0582 (3)
C100.05027 (10)0.36298 (13)0.35126 (8)0.0321 (3)
C110.01913 (10)0.46703 (13)0.29946 (8)0.0343 (3)
H110.08490.49850.31650.041*
C120.00522 (10)0.52607 (14)0.22357 (8)0.0358 (3)
H120.04390.59620.18890.043*
C130.10122 (11)0.48215 (15)0.19885 (8)0.0370 (3)
C140.17152 (11)0.37719 (16)0.24926 (9)0.0407 (3)
H140.23710.34590.23200.049*
C150.14613 (10)0.31872 (15)0.32406 (9)0.0369 (3)
H150.19460.24700.35780.044*
O160.13358 (9)0.53308 (12)0.12557 (7)0.0498 (3)
C170.06605 (15)0.64537 (19)0.07522 (11)0.0580 (4)
H17A0.01080.60880.05130.087*
H17B0.09850.67480.02590.087*
H17C0.06400.72970.11380.087*
C180.21576 (10)0.34911 (13)0.54706 (8)0.0315 (3)
C190.24241 (11)0.48377 (14)0.51540 (9)0.0397 (3)
H190.18560.53750.47490.048*
C200.35037 (12)0.54021 (16)0.54212 (10)0.0462 (3)
H200.36750.63130.51920.055*
C210.43355 (12)0.46435 (16)0.60222 (9)0.0458 (3)
H210.50780.50290.62030.055*
C220.40810 (11)0.33296 (16)0.63563 (9)0.0428 (3)
H220.46460.28170.67780.051*
C230.30042 (11)0.27471 (14)0.60821 (8)0.0364 (3)
H230.28410.18330.63130.044*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0432 (7)0.0409 (7)0.0367 (7)0.0017 (5)0.0154 (5)0.0031 (5)
C20.0539 (9)0.0616 (9)0.0454 (8)0.0123 (7)0.0234 (7)0.0019 (7)
C30.0396 (7)0.0450 (7)0.0501 (8)0.0072 (6)0.0209 (6)0.0019 (6)
N40.0306 (5)0.0407 (5)0.0386 (6)0.0036 (4)0.0129 (4)0.0008 (5)
C50.0296 (6)0.0411 (6)0.0361 (6)0.0010 (5)0.0102 (5)0.0007 (5)
C60.0268 (6)0.0368 (6)0.0324 (6)0.0011 (4)0.0080 (5)0.0010 (5)
C70.0289 (6)0.0363 (6)0.0314 (6)0.0011 (5)0.0094 (5)0.0005 (5)
C7A0.0323 (6)0.0369 (6)0.0342 (6)0.0004 (5)0.0116 (5)0.0018 (5)
C80.0310 (7)0.0497 (7)0.0469 (8)0.0026 (6)0.0070 (6)0.0037 (6)
O90.0336 (6)0.0685 (7)0.0695 (7)0.0141 (5)0.0069 (5)0.0018 (6)
C100.0260 (6)0.0391 (6)0.0304 (6)0.0005 (5)0.0055 (4)0.0013 (5)
C110.0271 (6)0.0411 (6)0.0349 (6)0.0036 (5)0.0079 (5)0.0021 (5)
C120.0323 (6)0.0390 (6)0.0343 (6)0.0043 (5)0.0046 (5)0.0034 (5)
C130.0326 (6)0.0461 (7)0.0323 (6)0.0012 (5)0.0082 (5)0.0038 (5)
C140.0270 (6)0.0565 (8)0.0405 (7)0.0073 (5)0.0120 (5)0.0070 (6)
C150.0267 (6)0.0470 (7)0.0362 (6)0.0056 (5)0.0059 (5)0.0064 (5)
O160.0450 (6)0.0659 (6)0.0418 (5)0.0064 (5)0.0170 (4)0.0167 (5)
C170.0609 (10)0.0662 (10)0.0462 (9)0.0048 (8)0.0120 (7)0.0216 (8)
C180.0286 (6)0.0388 (6)0.0278 (6)0.0005 (5)0.0085 (4)0.0034 (5)
C190.0360 (7)0.0394 (6)0.0413 (7)0.0013 (5)0.0047 (5)0.0023 (5)
C200.0433 (8)0.0435 (7)0.0496 (8)0.0106 (6)0.0071 (6)0.0017 (6)
C210.0346 (7)0.0561 (8)0.0433 (8)0.0096 (6)0.0033 (6)0.0054 (6)
C220.0337 (7)0.0550 (8)0.0355 (7)0.0004 (6)0.0005 (5)0.0007 (6)
C230.0339 (6)0.0435 (7)0.0307 (6)0.0004 (5)0.0057 (5)0.0025 (5)
Geometric parameters (Å, º) top
C1—C7A1.4929 (18)C11—H110.9500
C1—C21.540 (2)C12—C131.3805 (18)
C1—H1A0.9900C12—H120.9500
C1—H1B0.9900C13—O161.3701 (16)
C2—C31.530 (2)C13—C141.3935 (18)
C2—H2A0.9900C14—C151.3771 (19)
C2—H2B0.9900C14—H140.9500
C3—N41.4645 (16)C15—H150.9500
C3—H3A0.9900O16—C171.4247 (18)
C3—H3B0.9900C17—H17A0.9800
N4—C7A1.3466 (16)C17—H17B0.9800
N4—C51.3773 (17)C17—H17C0.9800
C5—C61.4019 (17)C18—C191.3943 (18)
C5—C81.4314 (18)C18—C231.3965 (17)
C6—C71.4189 (17)C19—C201.3833 (19)
C6—C101.4768 (17)C19—H190.9500
C7—C7A1.3941 (17)C20—C211.385 (2)
C7—C181.4743 (17)C20—H200.9500
C8—O91.2221 (17)C21—C221.375 (2)
C8—H80.9500C21—H210.9500
C10—C111.3915 (17)C22—C231.3873 (18)
C10—C151.3987 (17)C22—H220.9500
C11—C121.3889 (18)C23—H230.9500
C7A—C1—C2102.16 (11)C12—C11—H11119.1
C7A—C1—H1A111.3C10—C11—H11119.1
C2—C1—H1A111.3C13—C12—C11119.56 (11)
C7A—C1—H1B111.3C13—C12—H12120.2
C2—C1—H1B111.3C11—C12—H12120.2
H1A—C1—H1B109.2O16—C13—C12124.55 (12)
C3—C2—C1106.90 (11)O16—C13—C14115.71 (12)
C3—C2—H2A110.3C12—C13—C14119.73 (12)
C1—C2—H2A110.3C15—C14—C13120.19 (12)
C3—C2—H2B110.3C15—C14—H14119.9
C1—C2—H2B110.3C13—C14—H14119.9
H2A—C2—H2B108.6C14—C15—C10121.18 (12)
N4—C3—C2101.49 (11)C14—C15—H15119.4
N4—C3—H3A111.5C10—C15—H15119.4
C2—C3—H3A111.5C13—O16—C17116.83 (12)
N4—C3—H3B111.5O16—C17—H17A109.5
C2—C3—H3B111.5O16—C17—H17B109.5
H3A—C3—H3B109.3H17A—C17—H17B109.5
C7A—N4—C5110.43 (10)O16—C17—H17C109.5
C7A—N4—C3114.25 (11)H17A—C17—H17C109.5
C5—N4—C3135.27 (11)H17B—C17—H17C109.5
N4—C5—C6106.52 (11)C19—C18—C23118.09 (11)
N4—C5—C8123.78 (11)C19—C18—C7120.98 (11)
C6—C5—C8129.66 (12)C23—C18—C7120.93 (11)
C5—C6—C7107.96 (11)C20—C19—C18120.89 (12)
C5—C6—C10125.52 (11)C20—C19—H19119.6
C7—C6—C10126.37 (11)C18—C19—H19119.6
C7A—C7—C6106.08 (11)C19—C20—C21120.23 (13)
C7A—C7—C18125.87 (11)C19—C20—H20119.9
C6—C7—C18128.00 (11)C21—C20—H20119.9
N4—C7A—C7108.99 (11)C22—C21—C20119.64 (13)
N4—C7A—C1110.30 (11)C22—C21—H21120.2
C7—C7A—C1140.70 (12)C20—C21—H21120.2
O9—C8—C5125.17 (14)C21—C22—C23120.45 (13)
O9—C8—H8117.4C21—C22—H22119.8
C5—C8—H8117.4C23—C22—H22119.8
C11—C10—C15117.59 (11)C22—C23—C18120.67 (12)
C11—C10—C6122.40 (11)C22—C23—H23119.7
C15—C10—C6120.01 (11)C18—C23—H23119.7
C12—C11—C10121.74 (12)
C7A—C1—C2—C321.22 (15)C5—C6—C10—C1155.01 (18)
C1—C2—C3—N421.05 (15)C7—C6—C10—C11129.87 (14)
C2—C3—N4—C7A13.49 (15)C5—C6—C10—C15124.61 (14)
C2—C3—N4—C5169.27 (14)C7—C6—C10—C1550.51 (18)
C7A—N4—C5—C60.94 (14)C15—C10—C11—C120.26 (18)
C3—N4—C5—C6178.26 (13)C6—C10—C11—C12179.88 (11)
C7A—N4—C5—C8177.15 (12)C10—C11—C12—C130.67 (19)
C3—N4—C5—C80.2 (2)C11—C12—C13—O16179.91 (12)
N4—C5—C6—C70.34 (14)C11—C12—C13—C141.2 (2)
C8—C5—C6—C7177.60 (13)O16—C13—C14—C15179.78 (13)
N4—C5—C6—C10176.21 (11)C12—C13—C14—C150.8 (2)
C8—C5—C6—C101.7 (2)C13—C14—C15—C100.2 (2)
C5—C6—C7—C7A0.35 (14)C11—C10—C15—C140.68 (19)
C10—C6—C7—C7A175.48 (11)C6—C10—C15—C14179.68 (12)
C5—C6—C7—C18177.23 (12)C12—C13—O16—C173.9 (2)
C10—C6—C7—C186.9 (2)C14—C13—O16—C17177.17 (13)
C5—N4—C7A—C71.19 (14)C7A—C7—C18—C19142.11 (13)
C3—N4—C7A—C7179.11 (10)C6—C7—C18—C1935.02 (19)
C5—N4—C7A—C1177.99 (10)C7A—C7—C18—C2337.43 (18)
C3—N4—C7A—C10.06 (15)C6—C7—C18—C23145.44 (13)
C6—C7—C7A—N40.93 (14)C23—C18—C19—C201.60 (19)
C18—C7—C7A—N4176.71 (11)C7—C18—C19—C20178.85 (13)
C6—C7—C7A—C1177.85 (15)C18—C19—C20—C211.1 (2)
C18—C7—C7A—C14.5 (2)C19—C20—C21—C220.4 (2)
C2—C1—C7A—N413.35 (14)C20—C21—C22—C231.3 (2)
C2—C1—C7A—C7167.88 (16)C21—C22—C23—C180.7 (2)
N4—C5—C8—O91.0 (2)C19—C18—C23—C220.70 (19)
C6—C5—C8—O9178.61 (14)C7—C18—C23—C22179.74 (12)

Experimental details

Crystal data
Chemical formulaC21H19NO2
Mr317.37
Crystal system, space groupMonoclinic, P21/n
Temperature (K)193
a, b, c (Å)12.2276 (17), 9.1557 (10), 15.462 (2)
β (°) 104.174 (11)
V3)1678.3 (4)
Z4
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.30 × 0.20 × 0.07
Data collection
DiffractometerStoe IPDS 2T
diffractometer
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
23718, 4043, 2868
Rint0.067
(sin θ/λ)max1)0.661
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.039, 0.102, 1.02
No. of reflections4043
No. of parameters218
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.17, 0.16

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

 

References

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