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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 64| Part 9| September 2008| Pages o1708-o1709
doi:10.1107/S1600536808024690

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

P. Parthiban,a K. Thirumurugan,b V. Ramkumar,c S. Pazhamalaid and Yeon Tae Jeonga*

aDivision of Image Science and Information Engineering, Pukyong National University, Busan 608 739, Republic of Korea, bOrchid Chemical and Pharmaceuticals Ltd, R&D Centre, Sholinganallur, Chennai, Tamilnadu, India, cDepartment of Chemistry, IIT Madras, Chennai, TamilNadu, India, and dDepartment of Chemistry, Annamalai University, Annamalai Nagar, Chidambaram, Tamilnadu, India
*Correspondence e-mail: ytjeong@pknu.ac.kr

(Received 25 July 2008; accepted 1 August 2008; online 6 August 2008)

The title compound, C20H19F2NO, exhibits a chair–chair conformation, with the aryl groups in the heterocycle in equatorial orientations and oriented at an angle of 33.35 (3)° to one another. A crystallographic mirror plane, passing through the N atom, the C and O atoms of the carbonyl group and the C atom in the 7-position, bis­ects the mol­ecule. The mol­ecular structure is stabilized by one C—H⋯N inter­action and the crystal structure is stabilized by a weak C—H⋯π inter­action.

Related literature

For related literature, see: Barker et al. (2005[Barker, D., Lin, D. H. S., Carland, J. E., Chu, C. P. Y., Chebib, M., Brimble, M. A., Savage, G. P. & McLeod, M. D. (2005). Bioorg. Med. Chem. 13, 4565-4575.]); Dunitz et al. (1997[Dunitz, J. D. & Tailor, R. (1997). Chem. Eur. J. 3, 89-98.]); Evans et al. (1997[Evans, T. A. & Seddon, K. R. (1997). Chem. Commun. pp. 2023-2024.]); Jeyaraman et al. (1981[Jeyaraman, R. & Avila, S. (1981). Chem. Rev. 81, 149-174.]); Padegimas et al. (1972[Padegimas, S. J. & Kovacic, P. (1972). J. Org. Chem. 37, 2672-2676.]); Smith-Verdier et al. (1983[Smith-Verdier, P., Florencio, F. & García-Blanco, S. (1983). Acta Cryst. C39, 101-103.]); Web et al. (1967[Web, N. C. & Becker, M. R. (1967). J. Chem. Soc. B, pp. 1317-1321.]); Wiechert et al. (1997[Wiechert, D., Mootz, D. & Dahlems, T. (1997). J. Am. Chem. Soc. 119, 12665-12666.]); Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Ramachandran et al. (2007[Ramachandran, R., Parthiban, P., Doddi, A., Ramkumar, V. & Kabilan, S. (2007). Acta Cryst. E63, o4559.]); Vijayalakshmi et al. (2000[Vijayalakshmi, L., Parthasarathi, V., Venkatraj, M. & Jeyaraman, R. (2000). Acta Cryst. C56, 1240-1241.]).

[Scheme 1]

Experimental

Crystal data

  • C20H19F2NO

  • Mr = 327.36

  • Orthorhombic, P n m a

  • a = 7.3844 (2) Å

  • b = 21.5172 (10) Å

  • c = 10.2608 (4) Å

  • V = 1630.36 (11) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 298 (2) K

  • 0.35 × 0.19 × 0.15 mm
Data collection

  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 1999[Bruker (1999). SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.967, Tmax = 0.986

  • 11640 measured reflections

  • 2069 independent reflections

  • 1507 reflections with I > 2σ(I)

  • Rint = 0.023
Refinement

  • R[F2 > 2σ(F2)] = 0.051

  • wR(F2) = 0.154

  • S = 1.03

  • 2069 reflections

  • 118 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.26 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C4—H4B⋯N1 0.97 2.48 2.923 (3) 108
C11—H11⋯Cg1i 0.93 2.93 3.862 (2) 175
Symmetry code: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+{\script{3\over 2}}]. Cg1 is the centroid of the C6–C11 ring.

Data collection: APEX2 (Bruker–Nonius, 2004[Bruker-Nonius (2004). APEX2 and SAINT-Plus. Bruker-Nonius, Delft, The Netherlands.]); cell refinement: APEX2; data reduction: SAINT-Plus (Bruker–Nonius, 2004[Bruker-Nonius (2004). APEX2 and SAINT-Plus. Bruker-Nonius, Delft, The Netherlands.]); 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: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808024690/bx2166sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808024690/bx2166Isup2.hkl

checkCIF report


Comment top

Azabicyclic ketones are important class of heterocycles due to their broad spectrum biological activities (Jeyaraman & Avila, 1981; Barker et al., 2005). Moreover, the fluorine substituted organic molecules are valuable due to the significance of C—F bonds in some bioorganic systems (Evans & Seddon, 1997; Dunitz & Tailor, 1997). Hence, the biological significance of the hydrogen bonds involving fluorine atom have attracted much attention (Ramachandran et al., 2007;Wiechert et al., 1997). Owing to the diverse possibilities in conformations, viz.,chair-chair (Vijayalakshmi et al., 2000), chair-boat (Smith-Verdier et al., 1983) and boat-boat (Padegimas & Kovacic, 1972) for the azabicycle, the present crystal study was undertaken to explore the conformation, stereochemistry and bondings in the title compound.The study of torsion angles, asymmetry parameters and least-squares plane calculation of the title compound shows that the piperidine ring adopts near ideal chair conformation with the deviation of ring atoms N1 and C5 from the C1/C2/C1a/C2a plane by 0.659 (3) and -0.693 (3)Å respectively, the q(2) and q(3) are 0.0165 (16) and -0.6032 (16) Å. The total puckering amplitude, QT = 0.6034 (16)Å and θ = 178.44 (15)°. The cyclohexane ring deviate from the ideal chair conformation by the deviation of ring atoms C4 and C5 from the C2/C3/C2a/C3a plane by 0.527 (4) and - 0.727 (3)Å respectively. For the cyclohexane part, the q(2) and q(3) are 0.1472 (18) and -0.5470 (17)Å respectively. The total puckering amplitude, QT = 0.5664 (17) and θ =164.95 (18)° (Cremer & Pople, 1975; Web & Becker, 1967).Hence, the title compound C20 H19F2NO, exists in twin-chair conformation with equatorial orientations of the 3-fluorophenyl groups on the heterocycle and are orientated at an angle of 33.35 (3) ° to each other. The torsion angles of C5—C2—C1—C6 and its mirror plane C5—C2a—C1a—C6a is 178.51 (6)°.

Related literature top

For related literature, see: Barker et al. (2005); Dunitz et al. (1997); Evans et al. (1997); Jeyaraman et al. (1981); Padegimas et al. (1972); Smith-Verdier et al. (1983); Web et al. (1967); Wiechert et al. (1997); Cremer & Pople (1975); Ramachandran et al. (2007); Vijayalakshmi et al. (2000).

Experimental top

In a warm solution of ammonium acetate (0.075 mol) in 50 ml of absolute ethanol, a mixture of cyclohexanone (0.05 mol) and meta fluorobenzaldehyde (0.1 mol) was added and very gently warmed on a hot plate till the yellow color formed during the mixing of the reactants and stirred to the formation of the product. Then, the compound was separated by filtration and washed with 1:5 ethanol-ether mixture. Thus, the separated crude compound was purified by recrystallization from ethanol to obtain the colorless diffraction quality crystals of 2,4-bis (3-fluorophenyl)-3-azabicyclo [3.3.1]nonan-9-one.

Refinement top

Nitrogen H atoms were located in a difference Fourier map and refined isotropically. Other hydrogen atoms were fixed geometrically and allowed to ride on the parent carbon atoms,with aromatic C—H =0.93 Å, aliphatic C—H = 0.98Å 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).

Computing details top

Data collection: APEX2 (Bruker–Nonius, 2004); cell refinement: APEX2 (Bruker–Nonius, 2004); data reduction: SAINT-Plus (Bruker–Nonius, 2004); 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: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. ORTEP of the molecule with atoms represented as 30% probability ellipsoids.[symmetry code: _a: x,1/2-y, z]
2,4-Bis(3-fluorophenyl)-3-azabicyclo[3.3.1]nonan-9-one top
Crystal data top
C20H19F2NOF(000) = 688
Mr = 327.36Dx = 1.334 Mg m−3
Orthorhombic, PnmaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2nCell parameters from 3860 reflections
a = 7.3844 (2) Åθ = 2.2–27.8°
b = 21.5172 (10) ŵ = 0.10 mm−1
c = 10.2608 (4) ÅT = 298 K
V = 1630.36 (11) Å3Needle, colourless
Z = 40.35 × 0.19 × 0.15 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer		2069 independent reflections
Radiation source: fine-focus sealed tube1507 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.023
ϕ and ω scansθmax = 28.3°, θmin = 1.9°
Absorption correction: multi-scan
(SADABS; Bruker, 1999)		h = −9→9
Tmin = 0.967, Tmax = 0.986k = −28→27
11640 measured reflectionsl = −13→13
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)] = 0.051Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.154H atoms treated by a mixture of independent and constrained refinement
S = 1.03 w = 1/[σ2(Fo2) + (0.0736P)2 + 0.4778P]
where P = (Fo2 + 2Fc2)/3
2069 reflections(Δ/σ)max < 0.001
118 parametersΔρmax = 0.27 e Å−3
0 restraintsΔρmin = −0.26 e Å−3
Crystal data top
C20H19F2NOV = 1630.36 (11) Å3
Mr = 327.36Z = 4
Orthorhombic, PnmaMo Kα radiation
a = 7.3844 (2) ŵ = 0.10 mm−1
b = 21.5172 (10) ÅT = 298 K
c = 10.2608 (4) Å0.35 × 0.19 × 0.15 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer		2069 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 1999)		1507 reflections with I > 2σ(I)
Tmin = 0.967, Tmax = 0.986Rint = 0.023
11640 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0510 restraints
wR(F2) = 0.154H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.27 e Å−3
2069 reflectionsΔρmin = −0.26 e Å−3
118 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
C10.9282 (2)0.30645 (7)0.60735 (13)0.0415 (4)
H10.89100.30520.69900.050*
C20.75387 (19)0.30789 (7)0.52202 (15)0.0444 (4)
H20.68130.34410.54680.053*
C30.7856 (2)0.30939 (8)0.37344 (15)0.0482 (4)
H3A0.67070.31660.33020.058*
H3B0.86460.34410.35290.058*
C40.8693 (3)0.25000.3196 (2)0.0501 (6)
H4A0.85650.25000.22550.060*
H4B0.99780.25000.33940.060*
C50.6479 (3)0.25000.5518 (2)0.0460 (5)
C61.0432 (2)0.36362 (7)0.58774 (14)0.0436 (4)
C71.1855 (2)0.36471 (8)0.49973 (17)0.0509 (4)
H71.21530.32940.45220.061*
C81.2815 (2)0.41854 (9)0.4838 (2)0.0603 (5)
C91.2457 (3)0.47171 (9)0.5505 (2)0.0723 (6)
H91.31390.50750.53710.087*
C101.1056 (3)0.47077 (9)0.6385 (2)0.0767 (7)
H101.07750.50650.68530.092*
C111.0059 (3)0.41717 (8)0.65820 (19)0.0599 (5)
H110.91280.41700.71930.072*
F11.42123 (18)0.41845 (6)0.39681 (15)0.0962 (5)
N11.0305 (2)0.25000.57975 (17)0.0395 (4)
O10.4936 (2)0.25000.59191 (18)0.0638 (5)
H1A1.127 (3)0.25000.629 (2)0.047 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0426 (8)0.0480 (9)0.0338 (7)0.0033 (6)0.0003 (6)−0.0020 (6)
C20.0364 (7)0.0515 (10)0.0454 (8)0.0071 (6)0.0012 (6)−0.0016 (7)
C30.0432 (8)0.0592 (10)0.0423 (8)−0.0006 (7)−0.0067 (6)0.0080 (7)
C40.0439 (11)0.0734 (16)0.0331 (10)0.000−0.0014 (9)0.000
C50.0361 (11)0.0656 (15)0.0362 (10)0.0000.0020 (8)0.000
C60.0450 (8)0.0426 (9)0.0431 (7)0.0051 (6)−0.0104 (6)−0.0028 (6)
C70.0511 (9)0.0455 (9)0.0560 (9)−0.0018 (7)−0.0026 (7)−0.0016 (7)
C80.0528 (10)0.0552 (11)0.0731 (12)−0.0072 (8)−0.0096 (9)0.0110 (9)
C90.0659 (12)0.0455 (11)0.1056 (17)−0.0076 (9)−0.0312 (12)0.0070 (11)
C100.0815 (14)0.0464 (11)0.1024 (16)0.0107 (10)−0.0309 (13)−0.0217 (11)
C110.0610 (10)0.0555 (11)0.0632 (10)0.0109 (8)−0.0095 (9)−0.0158 (8)
F10.0816 (9)0.0895 (10)0.1176 (11)−0.0267 (7)0.0191 (8)0.0147 (8)
N10.0367 (9)0.0412 (10)0.0407 (9)0.000−0.0063 (7)0.000
O10.0408 (9)0.0867 (14)0.0639 (11)0.0000.0146 (8)0.000
Geometric parameters (Å, º) top
C1—N11.4585 (17)C5—C2i1.5025 (19)
C1—C61.508 (2)C6—C71.386 (2)
C1—C21.557 (2)C6—C111.388 (2)
C1—H10.9800C7—C81.368 (2)
C2—C51.5025 (19)C7—H70.9300
C2—C31.543 (2)C8—C91.359 (3)
C2—H20.9800C8—F11.364 (2)
C3—C41.523 (2)C9—C101.373 (3)
C3—H3A0.9700C9—H90.9300
C3—H3B0.9700C10—C111.383 (3)
C4—C3i1.523 (2)C10—H100.9300
C4—H4A0.9700C11—H110.9300
C4—H4B0.9700N1—C1i1.4585 (17)
C5—O11.212 (2)N1—H1A0.87 (2)
N1—C1—C6111.20 (12)O1—C5—C2123.98 (8)
N1—C1—C2109.63 (12)O1—C5—C2i123.98 (8)
C6—C1—C2111.97 (12)C2—C5—C2i112.01 (17)
N1—C1—H1108.0C7—C6—C11118.42 (16)
C6—C1—H1108.0C7—C6—C1121.85 (13)
C2—C1—H1108.0C11—C6—C1119.73 (15)
C5—C2—C3107.30 (14)C8—C7—C6119.02 (16)
C5—C2—C1107.44 (13)C8—C7—H7120.5
C3—C2—C1115.49 (12)C6—C7—H7120.5
C5—C2—H2108.8C9—C8—F1118.52 (17)
C3—C2—H2108.8C9—C8—C7123.5 (2)
C1—C2—H2108.8F1—C8—C7117.96 (17)
C4—C3—C2113.73 (14)C8—C9—C10117.71 (19)
C4—C3—H3A108.8C8—C9—H9121.1
C2—C3—H3A108.8C10—C9—H9121.1
C4—C3—H3B108.8C9—C10—C11120.63 (18)
C2—C3—H3B108.8C9—C10—H10119.7
H3A—C3—H3B107.7C11—C10—H10119.7
C3i—C4—C3114.07 (18)C10—C11—C6120.68 (19)
C3i—C4—H4A108.7C10—C11—H11119.7
C3—C4—H4A108.7C6—C11—H11119.7
C3i—C4—H4B108.7C1i—N1—C1112.78 (16)
C3—C4—H4B108.7C1i—N1—H1A108.1 (8)
H4A—C4—H4B107.6C1—N1—H1A108.1 (8)
N1—C1—C2—C557.58 (16)C2—C1—C6—C1184.78 (17)
C6—C1—C2—C5−178.52 (13)C11—C6—C7—C8−1.2 (2)
N1—C1—C2—C3−62.09 (17)C1—C6—C7—C8178.18 (15)
C6—C1—C2—C361.81 (17)C6—C7—C8—C90.4 (3)
C5—C2—C3—C4−52.65 (18)C6—C7—C8—F1179.86 (15)
C1—C2—C3—C467.10 (18)F1—C8—C9—C10−179.43 (17)
C2—C3—C4—C3i44.0 (2)C7—C8—C9—C100.1 (3)
C3—C2—C5—O1−113.3 (2)C8—C9—C10—C110.4 (3)
C1—C2—C5—O1122.0 (2)C9—C10—C11—C6−1.2 (3)
C3—C2—C5—C2i65.0 (2)C7—C6—C11—C101.6 (3)
C1—C2—C5—C2i−59.8 (2)C1—C6—C11—C10−177.76 (16)
N1—C1—C6—C728.45 (19)C6—C1—N1—C1i175.53 (10)
C2—C1—C6—C7−94.57 (16)C2—C1—N1—C1i−60.11 (18)
N1—C1—C6—C11−152.20 (15)
Symmetry code: (i) x, −y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4B···N10.972.482.923 (3)108
C11—H11···Cg1ii0.932.933.862 (2)175
Symmetry code: (ii) x−1/2, −y+1/2, −z+3/2.

Experimental details

Crystal data
Chemical formulaC20H19F2NO
Mr327.36
Crystal system, space groupOrthorhombic, Pnma
Temperature (K)298
a, b, c (Å)7.3844 (2), 21.5172 (10), 10.2608 (4)
V (Å3)1630.36 (11)
Z4
Radiation typeMo Kα
µ (mm−1)0.10
Crystal size (mm)0.35 × 0.19 × 0.15
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 1999)
Tmin, Tmax0.967, 0.986
No. of measured, independent and
observed [I > 2σ(I)] reflections		11640, 2069, 1507
Rint0.023
(sin θ/λ)max (Å−1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.051, 0.154, 1.03
No. of reflections2069
No. of parameters118
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.27, −0.26

Computer programs: APEX2 (Bruker–Nonius, 2004), SAINT-Plus (Bruker–Nonius, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4B···N10.972.482.923 (3)108
C11—H11···Cg1i0.932.933.862 (2)175
Symmetry code: (i) x−1/2, −y+1/2, −z+3/2.
 

Acknowledgements

The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection. This research was supported by the second stage of the BK 21 program and Pukyong National University under the 2008 Postdoc program.

References

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ISSN: 2056-9890
Volume 64| Part 9| September 2008| Pages o1708-o1709
doi:10.1107/S1600536808024690
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