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

Keck, P.R.W.E.F.; Schollmeyer, D.; Laufer, S.

doi:10.1107/S1600536811031369

organic compounds

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ISSN: 2056-9890

Volume 67| Part 9| September 2011| Page o2292

doi:10.1107/S1600536811031369

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

Peter R. W. E. F. Keck,^a Dieter Schollmeyer ^b and Stefan Laufer ^a ^*

^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 1 August 2011; accepted 3 August 2011; online 11 August 2011)

The 4-chlorophenyl residue in the title compound, C₂₀H₁₆ClNO, is oriented at a dihedral angle of 53.6 (3)° towards the phenyl ring and 42.0 (9)° towards the pyrrole ring of the pyrrolizine template. The phenyl ring is oriented at a dihedral angle of 45.4 (4)° towards the pyrrole ring.

Related literature

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

Experimental

Crystal data

C₂₀H₁₆ClNO
M_r = 321.79
Monoclinic, C 2/c
a = 21.1526 (13) Å
b = 11.5723 (9) Å
c = 17.1484 (12) Å
β = 130.843 (4)°
V = 3175.5 (4) Å³
Z = 8
Mo Kα radiation
μ = 0.24 mm⁻¹
T = 193 K
0.34 × 0.31 × 0.05 mm

Data collection

Stoe IPDS 2T diffractometer
9492 measured reflections
3804 independent reflections
2633 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.040
wR(F²) = 0.117
S = 1.02
3804 reflections
208 parameters
H-atom parameters constrained
Δρ_max = 0.18 e Å⁻³
Δρ_min = −0.38 e Å⁻³

Data collection: X-AREA (Stoe & Cie, 2010 ); cell refinement: X-AREA; 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811031369/bt5600sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811031369/bt5600Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536811031369/bt5600Isup3.cml

checkCIF report

Comment top

Based on ML3000 (Laufer et al., 2001a,b) as dual COX/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-chlorophenyl residue is oriented at a dihedral angle of 42.0 (9)° and the plain phenyl ring is oriented at a dihedral angle of 45.4 (4)°. The two phenyl rings are oriented at a dihedral angle of 53.6 (3)° and both centromers show a distance of 5.07 (6) Å. The distance between the para C atoms of the rings (C13, C20) is 6.85 (0) Å.

Related literature top

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

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-chlorophenyl)-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 and precipitated out of diisopropylic ether to yield 1.13 g (69%). Crystals of the title compound were obtained by slow evaporation of ethanol at room temperature.

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

Fig. 1. View of compound I. Displacement ellipsoids are drawn at the 50% probability level.

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

Crystal data top

C₂₀H₁₆ClNO	F(000) = 1344
M_r = 321.79	D_x = 1.346 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 6848 reflections
a = 21.1526 (13) Å	θ = 2.5–29.7°
b = 11.5723 (9) Å	µ = 0.24 mm⁻¹
c = 17.1484 (12) Å	T = 193 K
β = 130.843 (4)°	Plate, colourless
V = 3175.5 (4) Å³	0.34 × 0.31 × 0.05 mm
Z = 8

Data collection top

Stoe IPDS 2T diffractometer	2633 reflections with I > 2σ(I)
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus	R_int = 0.036
Graphite monochromator	θ_max = 28.0°, θ_min = 2.6°
Detector resolution: 6.67 pixels mm^-1	h = −27→27
rotation method scans	k = −15→13
9492 measured reflections	l = −22→16
3804 independent reflections

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)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.117	H-atom parameters constrained
S = 1.02	w = 1/[σ²(F_o²) + (0.0654P)² + 0.4776P] where P = (F_o² + 2F_c²)/3
3804 reflections	(Δ/σ)_max = 0.001
208 parameters	Δρ_max = 0.18 e Å⁻³
0 restraints	Δρ_min = −0.38 e Å⁻³

Crystal data top

C₂₀H₁₆ClNO	V = 3175.5 (4) Å³
M_r = 321.79	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 21.1526 (13) Å	µ = 0.24 mm⁻¹
b = 11.5723 (9) Å	T = 193 K
c = 17.1484 (12) Å	0.34 × 0.31 × 0.05 mm
β = 130.843 (4)°

Data collection top

Stoe IPDS 2T diffractometer	2633 reflections with I > 2σ(I)
9492 measured reflections	R_int = 0.036
3804 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.040	0 restraints
wR(F²) = 0.117	H-atom parameters constrained
S = 1.02	Δρ_max = 0.18 e Å⁻³
3804 reflections	Δρ_min = −0.38 e Å⁻³
208 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	0.62354 (11)	0.11928 (15)	0.31943 (15)	0.0441 (4)
H1A	0.5719	0.0923	0.3037	0.053*
H1B	0.6721	0.0780	0.3810	0.053*
C2	0.61862 (13)	0.10249 (16)	0.22614 (16)	0.0510 (4)
H2A	0.6461	0.0294	0.2326	0.061*
H2B	0.5597	0.1007	0.1610	0.061*
C3	0.66451 (11)	0.20673 (16)	0.22833 (15)	0.0451 (4)
H3A	0.7241	0.1889	0.2663	0.054*
H3B	0.6379	0.2328	0.1578	0.054*
N4	0.65521 (8)	0.29317 (12)	0.28297 (10)	0.0375 (3)
C5	0.66339 (10)	0.41119 (14)	0.29645 (12)	0.0369 (3)
C6	0.64365 (9)	0.43919 (13)	0.35826 (12)	0.0351 (3)
C7	0.62553 (9)	0.33471 (14)	0.38334 (12)	0.0349 (3)
C7A	0.63337 (9)	0.24695 (14)	0.33439 (12)	0.0367 (3)
C8	0.69420 (10)	0.48273 (16)	0.25951 (13)	0.0423 (4)
H8	0.7003	0.5629	0.2748	0.051*
O9	0.71332 (9)	0.44865 (13)	0.20975 (11)	0.0543 (3)
C10	0.64265 (9)	0.55686 (14)	0.39052 (12)	0.0349 (3)
C11	0.60820 (10)	0.64988 (15)	0.32190 (13)	0.0411 (4)
H11	0.5853	0.6372	0.2530	0.049*
C12	0.60672 (11)	0.75998 (15)	0.35203 (14)	0.0435 (4)
H12	0.5839	0.8225	0.3047	0.052*
C13	0.63874 (10)	0.77793 (14)	0.45162 (14)	0.0401 (4)
C14	0.67412 (10)	0.68840 (14)	0.52186 (13)	0.0387 (3)
H14	0.6972	0.7020	0.5907	0.046*
C15	0.67564 (9)	0.57881 (14)	0.49104 (12)	0.0361 (3)
H15	0.6996	0.5171	0.5393	0.043*
Cl16	0.63185 (3)	0.91463 (4)	0.48838 (4)	0.05391 (15)
C17	0.59919 (9)	0.31301 (13)	0.44330 (12)	0.0343 (3)
C18	0.53753 (10)	0.37916 (15)	0.42983 (14)	0.0408 (4)
H18	0.5134	0.4426	0.3834	0.049*
C19	0.51117 (11)	0.35325 (16)	0.48348 (15)	0.0460 (4)
H19	0.4690	0.3988	0.4734	0.055*
C20	0.54598 (11)	0.26142 (17)	0.55167 (14)	0.0483 (4)
H20	0.5276	0.2435	0.5882	0.058*
C21	0.60775 (12)	0.19570 (17)	0.56642 (14)	0.0486 (4)
H21	0.6321	0.1328	0.6135	0.058*
C22	0.63404 (11)	0.22143 (15)	0.51282 (13)	0.0416 (4)
H22	0.6765	0.1759	0.5236	0.050*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0489 (9)	0.0362 (9)	0.0538 (10)	0.0032 (7)	0.0364 (8)	−0.0003 (7)
C2	0.0619 (11)	0.0429 (10)	0.0578 (11)	−0.0025 (8)	0.0434 (10)	−0.0094 (8)
C3	0.0520 (9)	0.0457 (9)	0.0490 (9)	−0.0016 (7)	0.0379 (8)	−0.0100 (8)
N4	0.0421 (7)	0.0388 (7)	0.0386 (7)	0.0002 (5)	0.0294 (6)	−0.0017 (6)
C5	0.0390 (7)	0.0386 (8)	0.0354 (8)	−0.0016 (6)	0.0254 (7)	−0.0023 (6)
C6	0.0361 (7)	0.0365 (8)	0.0337 (7)	0.0008 (6)	0.0232 (6)	−0.0010 (6)
C7	0.0355 (7)	0.0354 (8)	0.0354 (7)	0.0023 (6)	0.0239 (6)	0.0016 (6)
C7A	0.0386 (7)	0.0361 (8)	0.0396 (8)	0.0031 (6)	0.0274 (7)	0.0012 (7)
C8	0.0471 (8)	0.0455 (9)	0.0397 (8)	−0.0059 (7)	0.0308 (8)	−0.0039 (7)
O9	0.0679 (8)	0.0623 (9)	0.0545 (8)	−0.0101 (7)	0.0496 (7)	−0.0086 (6)
C10	0.0359 (7)	0.0352 (8)	0.0369 (8)	−0.0004 (6)	0.0253 (7)	0.0003 (6)
C11	0.0477 (8)	0.0389 (9)	0.0371 (8)	−0.0003 (7)	0.0279 (7)	0.0021 (7)
C12	0.0500 (9)	0.0348 (8)	0.0458 (9)	0.0020 (7)	0.0313 (8)	0.0062 (7)
C13	0.0452 (8)	0.0330 (8)	0.0518 (9)	−0.0034 (6)	0.0360 (8)	−0.0027 (7)
C14	0.0449 (8)	0.0397 (8)	0.0414 (8)	−0.0012 (7)	0.0325 (7)	−0.0022 (7)
C15	0.0403 (8)	0.0372 (8)	0.0372 (8)	0.0031 (6)	0.0281 (7)	0.0032 (6)
Cl16	0.0722 (3)	0.0334 (2)	0.0704 (3)	−0.00204 (19)	0.0529 (3)	−0.0052 (2)
C17	0.0361 (7)	0.0326 (8)	0.0366 (8)	−0.0022 (6)	0.0248 (7)	−0.0015 (6)
C18	0.0424 (8)	0.0369 (8)	0.0482 (9)	0.0026 (6)	0.0319 (8)	0.0024 (7)
C19	0.0486 (9)	0.0449 (9)	0.0595 (10)	−0.0057 (7)	0.0420 (9)	−0.0083 (8)
C20	0.0591 (10)	0.0515 (10)	0.0512 (10)	−0.0127 (8)	0.0434 (9)	−0.0072 (8)
C21	0.0592 (10)	0.0454 (10)	0.0467 (9)	−0.0022 (8)	0.0370 (9)	0.0062 (8)
C22	0.0452 (8)	0.0403 (9)	0.0427 (8)	0.0030 (7)	0.0302 (7)	0.0035 (7)

Geometric parameters (Å, º) top

C1—C7A	1.491 (2)	C10—C11	1.397 (2)
C1—C2	1.546 (3)	C11—C12	1.383 (2)
C1—H1A	0.9900	C11—H11	0.9500
C1—H1B	0.9900	C12—C13	1.380 (3)
C2—C3	1.533 (3)	C12—H12	0.9500
C2—H2A	0.9900	C13—C14	1.380 (2)
C2—H2B	0.9900	C13—Cl16	1.7440 (17)
C3—N4	1.469 (2)	C14—C15	1.382 (2)
C3—H3A	0.9900	C14—H14	0.9500
C3—H3B	0.9900	C15—H15	0.9500
N4—C7A	1.345 (2)	C17—C22	1.392 (2)
N4—C5	1.377 (2)	C17—C18	1.395 (2)
C5—C6	1.408 (2)	C18—C19	1.385 (2)
C5—C8	1.432 (2)	C18—H18	0.9500
C6—C7	1.417 (2)	C19—C20	1.383 (3)
C6—C10	1.475 (2)	C19—H19	0.9500
C7—C7A	1.395 (2)	C20—C21	1.385 (3)
C7—C17	1.476 (2)	C20—H20	0.9500
C8—O9	1.224 (2)	C21—C22	1.383 (3)
C8—H8	0.9500	C21—H21	0.9500
C10—C15	1.396 (2)	C22—H22	0.9500

C7A—C1—C2	102.13 (15)	C15—C10—C11	117.63 (15)
C7A—C1—H1A	111.3	C15—C10—C6	120.84 (14)
C2—C1—H1A	111.3	C11—C10—C6	121.52 (15)
C7A—C1—H1B	111.3	C12—C11—C10	121.46 (16)
C2—C1—H1B	111.3	C12—C11—H11	119.3
H1A—C1—H1B	109.2	C10—C11—H11	119.3
C3—C2—C1	105.23 (14)	C13—C12—C11	119.22 (16)
C3—C2—H2A	110.7	C13—C12—H12	120.4
C1—C2—H2A	110.7	C11—C12—H12	120.4
C3—C2—H2B	110.7	C12—C13—C14	120.94 (16)
C1—C2—H2B	110.7	C12—C13—Cl16	119.62 (14)
H2A—C2—H2B	108.8	C14—C13—Cl16	119.42 (13)
N4—C3—C2	101.81 (13)	C13—C14—C15	119.33 (15)
N4—C3—H3A	111.4	C13—C14—H14	120.3
C2—C3—H3A	111.4	C15—C14—H14	120.3
N4—C3—H3B	111.4	C14—C15—C10	121.41 (15)
C2—C3—H3B	111.4	C14—C15—H15	119.3
H3A—C3—H3B	109.3	C10—C15—H15	119.3
C7A—N4—C5	110.10 (14)	C22—C17—C18	118.26 (15)
C7A—N4—C3	113.20 (14)	C22—C17—C7	119.75 (14)
C5—N4—C3	136.70 (15)	C18—C17—C7	121.94 (15)
N4—C5—C6	106.74 (14)	C19—C18—C17	120.67 (16)
N4—C5—C8	122.86 (15)	C19—C18—H18	119.7
C6—C5—C8	130.15 (16)	C17—C18—H18	119.7
C5—C6—C7	107.71 (14)	C20—C19—C18	120.32 (16)
C5—C6—C10	125.36 (15)	C20—C19—H19	119.8
C7—C6—C10	126.92 (14)	C18—C19—H19	119.8
C7A—C7—C6	106.05 (14)	C19—C20—C21	119.58 (16)
C7A—C7—C17	122.87 (14)	C19—C20—H20	120.2
C6—C7—C17	131.02 (14)	C21—C20—H20	120.2
N4—C7A—C7	109.39 (14)	C22—C21—C20	120.13 (17)
N4—C7A—C1	110.50 (14)	C22—C21—H21	119.9
C7—C7A—C1	140.10 (16)	C20—C21—H21	119.9
O9—C8—C5	125.12 (17)	C21—C22—C17	121.02 (16)
O9—C8—H8	117.4	C21—C22—H22	119.5
C5—C8—H8	117.4	C17—C22—H22	119.5

C7A—C1—C2—C3	25.15 (18)	C6—C5—C8—O9	176.32 (17)
C1—C2—C3—N4	−25.45 (18)	C5—C6—C10—C15	−137.95 (16)
C2—C3—N4—C7A	16.96 (19)	C7—C6—C10—C15	41.8 (2)
C2—C3—N4—C5	−163.46 (18)	C5—C6—C10—C11	42.7 (2)
C7A—N4—C5—C6	−1.26 (18)	C7—C6—C10—C11	−137.55 (17)
C3—N4—C5—C6	179.14 (17)	C15—C10—C11—C12	0.1 (2)
C7A—N4—C5—C8	173.57 (15)	C6—C10—C11—C12	179.48 (15)
C3—N4—C5—C8	−6.0 (3)	C10—C11—C12—C13	−1.1 (3)
N4—C5—C6—C7	1.41 (17)	C11—C12—C13—C14	1.8 (3)
C8—C5—C6—C7	−172.90 (16)	C11—C12—C13—Cl16	−176.36 (13)
N4—C5—C6—C10	−178.77 (14)	C12—C13—C14—C15	−1.5 (2)
C8—C5—C6—C10	6.9 (3)	Cl16—C13—C14—C15	176.68 (12)
C5—C6—C7—C7A	−1.06 (17)	C13—C14—C15—C10	0.4 (2)
C10—C6—C7—C7A	179.13 (14)	C11—C10—C15—C14	0.2 (2)
C5—C6—C7—C17	−178.20 (15)	C6—C10—C15—C14	−179.16 (14)
C10—C6—C7—C17	2.0 (3)	C7A—C7—C17—C22	45.3 (2)
C5—N4—C7A—C7	0.60 (18)	C6—C7—C17—C22	−137.98 (18)
C3—N4—C7A—C7	−179.70 (13)	C7A—C7—C17—C18	−132.22 (17)
C5—N4—C7A—C1	179.45 (13)	C6—C7—C17—C18	44.5 (2)
C3—N4—C7A—C1	−0.85 (19)	C22—C17—C18—C19	−0.7 (2)
C6—C7—C7A—N4	0.30 (17)	C7—C17—C18—C19	176.81 (15)
C17—C7—C7A—N4	177.73 (14)	C17—C18—C19—C20	0.3 (3)
C6—C7—C7A—C1	−178.0 (2)	C18—C19—C20—C21	0.3 (3)
C17—C7—C7A—C1	−0.6 (3)	C19—C20—C21—C22	−0.4 (3)
C2—C1—C7A—N4	−15.54 (18)	C20—C21—C22—C17	−0.1 (3)
C2—C1—C7A—C7	162.8 (2)	C18—C17—C22—C21	0.7 (3)
N4—C5—C8—O9	2.8 (3)	C7—C17—C22—C21	−176.92 (16)

Experimental details

Crystal data
Chemical formula	C₂₀H₁₆ClNO
M_r	321.79
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	193
a, b, c (Å)	21.1526 (13), 11.5723 (9), 17.1484 (12)
β (°)	130.843 (4)
V (Å³)	3175.5 (4)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.24
Crystal size (mm)	0.34 × 0.31 × 0.05

Data collection
Diffractometer	Stoe IPDS 2T diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	9492, 3804, 2633
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.661

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.040, 0.117, 1.02
No. of reflections	3804
No. of parameters	208
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.18, −0.38

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

References

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. Web of Science CrossRef CAS IUCr Journals Google Scholar
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Stoe & Cie (2010). X-AREA and X-RED. Stoe & Cie GmbH, Darmstadt, Germany. Google Scholar