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Acta Crystallogr Sect E Struct Rep Online. 2009 June 1; 65(Pt 6): o1383.
Published online 2009 May 23. doi:  10.1107/S1600536809018686
PMCID: PMC2969524

2,4-Bis(2-methoxy­phenyl)-3-aza­bicyclo­[3.3.1]nonan-9-one

Abstract

In the title compound, C22H25NO3, the mol­ecule has a pseudo-mirror plane. The structure is a positional isomer of 2,4-bis(4-methoxy­phenyl)-3-aza­bicyclo­[3.3.1]nonan-9-one [Cox, McCabe, Milne & Sim (1985 [triangle]). J. Chem. Soc. Chem. Commun. pp. 626–628]. The 3-aza­bicyclo­[3.3.1]nonan-9-one moiety adopts a double chair conformation with equatorial orientations of both 2-methoxy­phenyl substituents on either side of the secondary amino group. The benzene rings are oriented at an angle of 33.86 (4)° with respect to each other and the meth­oxy groups point towards the carbonyl group. The crystal structure is stabilized by intermolecular N—H(...)π inter­actions.

Related literature

For prevalence and biological activities of 3-aza­bicyclo­nonan-9-ones, see: Hardick et al. (1996 [triangle]); Jeyaraman & Avila (1981 [triangle]); Barker et al. (2005 [triangle]). For similiar structures, see: Parthiban et al. (2008a [triangle],b [triangle]); Cox et al. (1985 [triangle]). For ring-puckering parameters, see: Cremer & Pople (1975 [triangle]).

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Object name is e-65-o1383-scheme1.jpg

Experimental

Crystal data

  • C22H25NO3
  • M r = 351.43
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1383-efi1.jpg
  • a = 7.8616 (2) Å
  • b = 20.8443 (6) Å
  • c = 11.4984 (3) Å
  • β = 95.670(10)°
  • V = 1874.37 (9) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 298 K
  • 0.58 × 0.42 × 0.35 mm

Data collection

  • Bruker APEXII CCD area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Bruker, 1999 [triangle]) T min = 0.945, T max = 0.972
  • 14712 measured reflections
  • 4527 independent reflections
  • 3202 reflections with I > 2σ(I)
  • R int = 0.023

Refinement

  • R[F 2 > 2σ(F 2)] = 0.048
  • wR(F 2) = 0.135
  • S = 1.03
  • 4527 reflections
  • 241 parameters
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.17 e Å−3
  • Δρmin = −0.25 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: APEX2; data reduction: SAINT-Plus (Bruker, 2004 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
N—H(...)π geometry (Å, ° )

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809018686/bx2207sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809018686/bx2207Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Acknowledgments

The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.

supplementary crystallographic information

Comment

Widespread interest in the chemistry of 3-azabicyclononan-9-ones is due to their presence in numerous naturally occurring alkaloids and broad spectrum biological activities (Jeyaraman & Avila, 1981; Hardick et al., 1996; Barker et al., 2005). Since the stereochemistry plays a crucial role in eliciting the biological response, it is immense to establish the stereochemistry of the biologically important molecules. Even though similar compounds show double chair conformation (Parthiban et al., 2008a,b), we have carried out the single-crystal XRD study for the title compound to know the impact of comparatively bulkier methoxy substituent on ortho position of the phenyl group, attached on either side of the secondary amino group.The molecule has a pseudo mirror plane.The structure is a positional isomer of 2,4-Bis(p-methoxyphenyl)-3-azabicyclo(3.3.1)nonan-9-one (Cox et al., 1985). The title compound C22H25NO3, exists in double chair conformation with an equatorial orientation of the ortho-methoxyphenyl group on both sides of the secondary amino group with the torsion angle of C8—C2—C1—C9 and C8—C6—C7—C15 are -179.66 (3) and -179.76 (4)°, respectively. In both aryl groups, the methoxy substituent point towards the carbonyl group at an angle of 33.86 (4)° to each other. A study of torsion angles, asymmetry parameters and least-squares plane calculation shows that the piperidine ring adopts near ideal chair conformation with the deviation of ring atoms N1 and C8 from the C1/C2/C6/C7 plane by -0.641 (3) and 0.718 (3) Å, respectively; QT = 0.6101 (15) Å, q(2)= 0.0490 (15) Å, q(3)= -0.6081 (15) Å, θ = 175.41 (14)° (Cremer & Pople, 1975) whereas the cyclohexane ring atoms C4 and C8 deviate from the C2/C3/C5/C6 plane by -0.537 (4) and 0.710 (3) Å, respectively; QT = 0.5528 (17) Å, q(2)= 0.1286 (17) Å, q(3)= -0.5376 (17) Å, θ = 166.55 (18)°.

Experimental

A mixture of cyclohexanone (4.90 g) and ortho-methoxybenzaldehyde (13.62 g) was added to a warm solution of ammonium acetate (5.78 g) in 50 ml of absolute ethanol. The mixture was gently warmed with stirring till the yellow color was formed during the mixing of the reactants and then allowed to stirring at room temperature up to the formation of product. At the end, the crude azabicyclic ketone was separated by filtration and washed with 1:5 ethanol–ether mixture till the solid became colorless. Recrystallization of the compound from ethanol gave X-ray diffraction quality crystals of 2,4-bis(2-methoxyphenyl)-3-azabicyclo[3.3.1]nonan-9-one.

Refinement

Nitrogen H atoms were located in a difference Fourier map and refined isotropically. Other H atoms were fixed geometrically and allowed to ride on the parent C atoms,with aromatic C—H = 0.93 Å, aliphatic C—H = 0.98 Å and methylen C—H = 0.97 Å. The displacement parameters were set for phenyl, methylen and aliphatic H atoms at Uiso(H) = 1.2Ueq(C).

Figures

Fig. 1.
View of the title molecule with atoms represented as 30% probability ellipsoids.
Fig. 2.
The N—H···π interactions.

Crystal data

C22H25NO3F(000) = 752
Mr = 351.43Dx = 1.245 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 4251 reflections
a = 7.8616 (2) Åθ = 2.6–27.0°
b = 20.8443 (6) ŵ = 0.08 mm1
c = 11.4984 (3) ÅT = 298 K
β = 95.867 (1)°Block, colourless
V = 1874.37 (9) Å30.58 × 0.42 × 0.35 mm
Z = 4

Data collection

Bruker APEXII CCD area-detector diffractometer4527 independent reflections
Radiation source: fine-focus sealed tube3202 reflections with I > 2σ(I)
graphiteRint = 0.023
[var phi] and ω scansθmax = 28.3°, θmin = 2.0°
Absorption correction: multi-scan (SADABS; Bruker, 1999)h = −9→10
Tmin = 0.945, Tmax = 0.972k = −27→26
14712 measured reflectionsl = −15→13

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.135H atoms treated by a mixture of independent and constrained refinement
S = 1.03w = 1/[σ2(Fo2) + (0.065P)2 + 0.3026P] where P = (Fo2 + 2Fc2)/3
4527 reflections(Δ/σ)max = 0.001
241 parametersΔρmax = 0.17 e Å3
0 restraintsΔρmin = −0.25 e Å3

Special details

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)

xyzUiso*/Ueq
C10.72892 (16)0.98913 (6)0.17176 (12)0.0343 (3)
H10.79740.98510.10550.041*
C20.85201 (18)1.00058 (7)0.28460 (14)0.0417 (3)
H20.92081.03890.27350.050*
C30.7636 (2)1.00894 (8)0.39684 (15)0.0531 (4)
H3A0.84791.02320.45890.064*
H3B0.67811.04240.38400.064*
C40.6779 (2)0.94870 (9)0.43724 (15)0.0582 (4)
H4A0.57020.94240.38940.070*
H4B0.65290.95450.51750.070*
C50.7881 (2)0.88909 (8)0.42979 (15)0.0552 (4)
H5A0.71790.85150.43900.066*
H5B0.87750.88960.49450.066*
C60.87146 (18)0.88257 (7)0.31544 (14)0.0435 (4)
H60.95210.84660.32290.052*
C70.74651 (17)0.87292 (6)0.20328 (13)0.0366 (3)
H70.81450.86890.13680.044*
C80.96882 (18)0.94334 (7)0.29817 (14)0.0431 (4)
C90.60420 (16)1.04380 (6)0.14722 (12)0.0336 (3)
C100.43367 (18)1.03906 (7)0.16792 (13)0.0415 (3)
H100.39471.00140.19940.050*
C110.32021 (19)1.08937 (8)0.14269 (15)0.0478 (4)
H110.20611.08510.15600.057*
C120.37750 (19)1.14550 (7)0.09793 (14)0.0467 (4)
H120.30191.17940.08180.056*
C130.54701 (18)1.15209 (7)0.07648 (13)0.0422 (3)
H130.58501.19030.04620.051*
C140.65935 (17)1.10152 (6)0.10043 (12)0.0352 (3)
C150.63790 (17)0.81319 (6)0.20774 (13)0.0372 (3)
C160.69939 (18)0.75399 (6)0.17200 (13)0.0402 (3)
C170.5962 (2)0.69992 (7)0.16825 (15)0.0500 (4)
H170.63720.66090.14360.060*
C180.4323 (2)0.70404 (8)0.20125 (16)0.0547 (4)
H180.36310.66770.19820.066*
C190.3707 (2)0.76145 (8)0.23863 (15)0.0515 (4)
H190.26100.76390.26180.062*
C200.47349 (18)0.81559 (7)0.24150 (14)0.0440 (4)
H200.43140.85430.26660.053*
C210.8836 (2)1.15648 (10)0.01693 (18)0.0661 (5)
H21A0.81961.1579−0.05870.099*
H21B1.00301.15190.00790.099*
H21C0.86561.19550.05830.099*
C220.9277 (2)0.69656 (8)0.09613 (18)0.0615 (5)
H22A0.93300.66410.15560.092*
H22B1.04020.70410.07360.092*
H22C0.85380.68250.02930.092*
N10.63559 (14)0.92907 (5)0.18328 (11)0.0358 (3)
O11.12212 (14)0.94572 (6)0.29471 (13)0.0676 (4)
O20.82804 (12)1.10343 (5)0.08112 (10)0.0470 (3)
O30.86248 (14)0.75428 (5)0.14027 (11)0.0532 (3)
H1A0.567 (2)0.9222 (7)0.1162 (15)0.046 (4)*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0332 (6)0.0317 (6)0.0388 (8)−0.0012 (5)0.0068 (6)−0.0005 (5)
C20.0361 (7)0.0370 (7)0.0508 (9)−0.0062 (6)−0.0013 (6)−0.0005 (6)
C30.0589 (10)0.0535 (9)0.0449 (10)0.0039 (8)−0.0036 (7)−0.0115 (7)
C40.0631 (11)0.0733 (12)0.0390 (9)−0.0011 (9)0.0097 (8)−0.0040 (8)
C50.0598 (10)0.0600 (10)0.0444 (10)−0.0077 (8)−0.0023 (8)0.0127 (8)
C60.0362 (7)0.0377 (7)0.0556 (10)0.0035 (6)−0.0008 (7)0.0060 (7)
C70.0354 (7)0.0309 (6)0.0446 (8)−0.0010 (5)0.0093 (6)0.0003 (6)
C80.0344 (7)0.0488 (8)0.0448 (9)−0.0028 (6)−0.0019 (6)0.0000 (7)
C90.0345 (7)0.0327 (6)0.0336 (8)−0.0008 (5)0.0029 (5)−0.0025 (5)
C100.0378 (7)0.0399 (7)0.0477 (9)−0.0026 (6)0.0091 (6)0.0008 (6)
C110.0347 (7)0.0532 (9)0.0567 (10)0.0050 (7)0.0110 (7)−0.0022 (8)
C120.0453 (8)0.0438 (8)0.0507 (10)0.0126 (7)0.0038 (7)−0.0008 (7)
C130.0473 (8)0.0356 (7)0.0433 (9)0.0015 (6)0.0033 (7)0.0029 (6)
C140.0339 (7)0.0374 (7)0.0346 (7)−0.0021 (6)0.0041 (5)−0.0008 (6)
C150.0397 (7)0.0348 (7)0.0371 (8)−0.0029 (6)0.0031 (6)0.0040 (6)
C160.0436 (8)0.0344 (7)0.0431 (9)−0.0013 (6)0.0060 (6)0.0058 (6)
C170.0620 (10)0.0343 (7)0.0540 (10)−0.0063 (7)0.0073 (8)0.0020 (7)
C180.0591 (10)0.0470 (9)0.0577 (11)−0.0202 (8)0.0045 (8)0.0071 (8)
C190.0427 (8)0.0565 (10)0.0561 (10)−0.0111 (7)0.0089 (7)0.0090 (8)
C200.0431 (8)0.0427 (8)0.0469 (9)−0.0021 (6)0.0086 (7)0.0025 (7)
C210.0463 (9)0.0827 (13)0.0698 (13)−0.0097 (9)0.0081 (8)0.0362 (10)
C220.0672 (11)0.0458 (9)0.0744 (13)0.0096 (8)0.0209 (9)−0.0044 (8)
N10.0344 (6)0.0299 (6)0.0419 (7)−0.0020 (5)−0.0015 (5)−0.0003 (5)
O10.0330 (6)0.0683 (8)0.1010 (11)−0.0040 (5)0.0034 (6)0.0059 (7)
O20.0359 (5)0.0468 (6)0.0593 (7)−0.0022 (4)0.0104 (5)0.0138 (5)
O30.0511 (6)0.0345 (5)0.0773 (8)0.0022 (5)0.0220 (6)−0.0021 (5)

Geometric parameters (Å, °)

C1—N11.4640 (16)C11—C121.373 (2)
C1—C91.5110 (17)C11—H110.9300
C1—C21.556 (2)C12—C131.387 (2)
C1—H10.9800C12—H120.9300
C2—C81.504 (2)C13—C141.3846 (19)
C2—C31.537 (2)C13—H130.9300
C2—H20.9800C14—O21.3674 (16)
C3—C41.520 (2)C15—C201.3879 (19)
C3—H3A0.9700C15—C161.4021 (19)
C3—H3B0.9700C16—O31.3684 (17)
C4—C51.522 (2)C16—C171.3868 (19)
C4—H4A0.9700C17—C181.383 (2)
C4—H4B0.9700C17—H170.9300
C5—C61.534 (2)C18—C191.376 (2)
C5—H5A0.9700C18—H180.9300
C5—H5B0.9700C19—C201.386 (2)
C6—C81.504 (2)C19—H190.9300
C6—C71.552 (2)C20—H200.9300
C6—H60.9800C21—O21.4227 (18)
C7—N11.4636 (16)C21—H21A0.9600
C7—C151.5136 (17)C21—H21B0.9600
C7—H70.9800C21—H21C0.9600
C8—O11.2109 (17)C22—O31.4216 (18)
C9—C101.3889 (18)C22—H22A0.9600
C9—C141.4044 (18)C22—H22B0.9600
C10—C111.388 (2)C22—H22C0.9600
C10—H100.9300N1—H1A0.907 (17)
N1—C1—C9109.89 (10)C11—C10—H10119.3
N1—C1—C2109.30 (11)C9—C10—H10119.3
C9—C1—C2112.12 (11)C12—C11—C10119.60 (13)
N1—C1—H1108.5C12—C11—H11120.2
C9—C1—H1108.5C10—C11—H11120.2
C2—C1—H1108.5C11—C12—C13120.61 (13)
C8—C2—C3109.05 (13)C11—C12—H12119.7
C8—C2—C1106.62 (11)C13—C12—H12119.7
C3—C2—C1114.94 (12)C14—C13—C12119.63 (13)
C8—C2—H2108.7C14—C13—H13120.2
C3—C2—H2108.7C12—C13—H13120.2
C1—C2—H2108.7O2—C14—C13123.71 (12)
C4—C3—C2114.56 (13)O2—C14—C9115.45 (12)
C4—C3—H3A108.6C13—C14—C9120.84 (12)
C2—C3—H3A108.6C20—C15—C16118.20 (13)
C4—C3—H3B108.6C20—C15—C7121.64 (12)
C2—C3—H3B108.6C16—C15—C7120.09 (12)
H3A—C3—H3B107.6O3—C16—C17123.81 (13)
C3—C4—C5112.60 (14)O3—C16—C15115.77 (12)
C3—C4—H4A109.1C17—C16—C15120.41 (13)
C5—C4—H4A109.1C18—C17—C16119.98 (15)
C3—C4—H4B109.1C18—C17—H17120.0
C5—C4—H4B109.1C16—C17—H17120.0
H4A—C4—H4B107.8C19—C18—C17120.47 (14)
C4—C5—C6114.58 (13)C19—C18—H18119.8
C4—C5—H5A108.6C17—C18—H18119.8
C6—C5—H5A108.6C18—C19—C20119.51 (14)
C4—C5—H5B108.6C18—C19—H19120.2
C6—C5—H5B108.6C20—C19—H19120.2
H5A—C5—H5B107.6C19—C20—C15121.41 (14)
C8—C6—C5107.83 (13)C19—C20—H20119.3
C8—C6—C7106.67 (12)C15—C20—H20119.3
C5—C6—C7115.74 (12)O2—C21—H21A109.5
C8—C6—H6108.8O2—C21—H21B109.5
C5—C6—H6108.8H21A—C21—H21B109.5
C7—C6—H6108.8O2—C21—H21C109.5
N1—C7—C15109.52 (11)H21A—C21—H21C109.5
N1—C7—C6110.07 (11)H21B—C21—H21C109.5
C15—C7—C6112.93 (11)O3—C22—H22A109.5
N1—C7—H7108.1O3—C22—H22B109.5
C15—C7—H7108.1H22A—C22—H22B109.5
C6—C7—H7108.1O3—C22—H22C109.5
O1—C8—C6124.11 (14)H22A—C22—H22C109.5
O1—C8—C2124.27 (14)H22B—C22—H22C109.5
C6—C8—C2111.62 (12)C7—N1—C1113.70 (10)
C10—C9—C14117.90 (12)C7—N1—H1A107.5 (10)
C10—C9—C1122.25 (12)C1—N1—H1A108.7 (10)
C14—C9—C1119.85 (11)C14—O2—C21117.45 (12)
C11—C10—C9121.42 (13)C16—O3—C22118.24 (12)
N1—C1—C2—C858.24 (14)C11—C12—C13—C140.0 (2)
C9—C1—C2—C8−179.66 (11)C12—C13—C14—O2179.37 (14)
N1—C1—C2—C3−62.72 (15)C12—C13—C14—C9−0.6 (2)
C9—C1—C2—C359.38 (15)C10—C9—C14—O2−179.60 (12)
C8—C2—C3—C4−51.29 (18)C1—C9—C14—O2−0.42 (19)
C1—C2—C3—C468.33 (18)C10—C9—C14—C130.4 (2)
C2—C3—C4—C543.6 (2)C1—C9—C14—C13179.54 (13)
C3—C4—C5—C6−45.3 (2)N1—C7—C15—C20−26.68 (19)
C4—C5—C6—C854.13 (17)C6—C7—C15—C2096.37 (16)
C4—C5—C6—C7−65.18 (18)N1—C7—C15—C16150.24 (13)
C8—C6—C7—N1−57.03 (14)C6—C7—C15—C16−86.71 (16)
C5—C6—C7—N162.93 (15)C20—C15—C16—O3−179.66 (13)
C8—C6—C7—C15−179.76 (11)C7—C15—C16—O33.3 (2)
C5—C6—C7—C15−59.81 (16)C20—C15—C16—C171.4 (2)
C5—C6—C8—O1117.71 (18)C7—C15—C16—C17−175.58 (13)
C7—C6—C8—O1−117.36 (17)O3—C16—C17—C18−179.58 (15)
C5—C6—C8—C2−62.84 (16)C15—C16—C17—C18−0.8 (2)
C7—C6—C8—C262.09 (16)C16—C17—C18—C19−0.4 (3)
C3—C2—C8—O1−118.78 (18)C17—C18—C19—C200.9 (3)
C1—C2—C8—O1116.57 (17)C18—C19—C20—C15−0.2 (2)
C3—C2—C8—C661.77 (16)C16—C15—C20—C19−1.0 (2)
C1—C2—C8—C6−62.88 (16)C7—C15—C20—C19176.01 (14)
N1—C1—C9—C1017.27 (18)C15—C7—N1—C1−177.14 (11)
C2—C1—C9—C10−104.49 (15)C6—C7—N1—C158.14 (15)
N1—C1—C9—C14−161.87 (12)C9—C1—N1—C7178.03 (11)
C2—C1—C9—C1476.37 (16)C2—C1—N1—C7−58.54 (15)
C14—C9—C10—C110.4 (2)C13—C14—O2—C21−9.8 (2)
C1—C9—C10—C11−178.73 (14)C9—C14—O2—C21170.19 (14)
C9—C10—C11—C12−1.0 (2)C17—C16—O3—C222.8 (2)
C10—C11—C12—C130.7 (2)C15—C16—O3—C22−176.03 (14)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N1—H1A···Cg1i0.90 (4)2.75 (4)3.58 (5)152.87 (3)

Symmetry codes: (i) −x+1, −y+2, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BX2207).

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