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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o1994–o1995.
Published online 2009 July 25. doi:  10.1107/S1600536809028529
PMCID: PMC2977122

1-Chloro­acetyl-2,6-bis­(3-fluoro­phen­yl)piperidin-4-one

Abstract

In the title compound C19H16ClF2NO2, the piperidone ring adopts a twist-boat conformation with the two out-of-plane atoms deviating by 0.544 (1) and 0.511 (1) Å from the plane through the remaining atoms in the ring. Sterically favoured non-H-atom C(...)O inter­molecular contacts are observed in the structure, within a 3.00 Å range. The crystal packing is stabilized by C—H(...)O and C—H(...)F hydrogen bonds and an inter­molecular π–π inter­action [centroid-centroid separation of 3.783 (1) Å]. Alternating C—H(...)O and C—H(...)F inter­molecular inter­actions generate chains running along the a axis, while a centrosymmetric R 2 2(16) ring involving C—H(...)O inter­actions is formed centred at (1/2, 1/2, 0).

Related literature

For background to the biological activity of piperidines and piperidones and their derivatives, see: Richardo et al. (1979 [triangle]); Schneider (1996 [triangle]); Mukhtar & Wright (2005 [triangle]); Fleet et al. (1990 [triangle]); Winkler & Holan (1989 [triangle]); Aridoss et al. (2007a [triangle], 2008 [triangle], 2009a [triangle]). For related structures, see: Gayathri et al. (2008 [triangle]); Ramachandran et al. (2008 [triangle]); Aridoss et al. (2009b [triangle]). For the synthesis and stereochemistry, see: Krishnapillay et al. (2000 [triangle]); Aridoss et al. (2007b [triangle]). For ring conformational analysis, see: Cremer & Pople (1975 [triangle]); Nardelli (1983 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-65-o1994-scheme1.jpg

Experimental

Crystal data

  • C19H16ClF2NO2
  • M r = 363.78
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1994-efi1.jpg
  • a = 10.7026 (8) Å
  • b = 8.2017 (6) Å
  • c = 19.0447 (15) Å
  • β = 100.629 (1)°
  • V = 1643.1 (2) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.27 mm−1
  • T = 293 K
  • 0.29 × 0.25 × 0.22 mm

Data collection

  • Bruker SMART APEX diffractometer
  • Absorption correction: none
  • 18143 measured reflections
  • 3875 independent reflections
  • 3515 reflections with I > 2σ(I)
  • R int = 0.018

Refinement

  • R[F 2 > 2σ(F 2)] = 0.039
  • wR(F 2) = 0.111
  • S = 1.03
  • 3875 reflections
  • 226 parameters
  • H-atom parameters constrained
  • Δρmax = 0.34 e Å−3
  • Δρmin = −0.35 e Å−3

Data collection: SMART (Bruker, 2001 [triangle]); cell refinement: SAINT (Bruker, 2001 [triangle]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97 and PARST (Nardelli, 1995 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809028529/bg2281sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809028529/bg2281Isup2.hkl

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

Acknowledgments

The authors thank Dr K. Ravikumar, Indian Institute of Chemical Technology, Hyderabad, India, for providing the X-ray data collection facility. GA and YTJ are grateful for the support provided by the second stage of the BK21 program, Republic of Korea. Financial support from the University Grants Commission (UGC-SAP) and the Department of Science & Technology (DST-FIST), Government of India, are acknowledged by DV for providing facilities to the department.

supplementary crystallographic information

Comment

Amides are a prominent functional group in chemistry due to their being an integral part in biologically important polymers such as peptides and proteins. Functionalized piperidines are among the most common building blocks in natural products, and, more interestingly, in many biologically active compounds such as anopterine, pergoline, scopolamine and morphine (Richardo et al., 1979, Schneider, 1996, Mukhtar & Wright, 2005). Piperidones also have high impact in medicinal field owing to their role as key chiral intermediates for the preparation of a variety of natural, synthetic and semi-synthetic pharmacophores with marked anticancer (Fleet et al., 1990) and anti-HIV activities (Winkler & Holan, 1989). Particularly, amides derived from 2,6-diarylpiperidin-4-ones exhibited marked antibacterial and antitubercular activities (Aridoss et al. 2007a, 2008, 2009a). As a corollary of these interesting biological and pharmaceutical properties and synthetic utility, substantial interest has been demonstrated towards 2,6-diarylpiperidin-4-ones (Krishnapillay et al., 2000, Aridoss et al., 2007b). Recently, we have disclosed the crystal structures of variously substituted 2,6-diarylpiperidin-4-ones and their derivatives (Gayathri et al. 2008, Ramachandran et al., 2008, Aridoss et al., 2009b). In the interest of above, crystal structure of 1-chloroacetyl-2,6-bis (3-fluorophenyl)-piperidin-4-one is reported here.

The molecular structure of compound (I) is illustrated in Fig.1. The sum of the angles at N1 (357.3 (3)°) is in accordance with sp2 hybridization. The dihedral angle between the two phenyl rings is 65.8 (1)°. Fluorine atoms (F1 and F2) lie above the plane of the phenyl rings to which they are attached by 0.041 (1) and 0.003 (2) Å, respectively. The torsion angle around O2—C6—C7—Cl1 indicates the planarity of chloroacetyl moiety. In the present structure, the piperidone ring adops a twist-boat conformation with atoms C1 and C4 deviating by 0.544 (1) and 0.511 (1) Å, respectively, from the least-sqaures plane defined by the remaining atoms (N1/C2/C3/C5) in the ring. When compared with the reported structures of piperidone derivatives (Gayathri et al., 2007, Ramachandran et al., 2008, Aridoss et al., 2009b), it is clear that the conformation of the piperidone ring is highly influenced by the substitutions at various positions. The puckering parameters (Cremer & Pople, 1975) and the smallest displacement asymmetry parameters (Nardelli, 1983) for piperidone ring are q2 = 0.671 (1) Å, q3 = 0.045 (1) Å; QT = 0.672 (1)Å and θ = 86.0 (1)°, respectively.

Sterically favoured short non-hydrogen intermolecular contacts are observed between O1 and C6 (-x + 1/2, y + 1/2, -z + 1/2) and C6 and O1 (-x + 1/2, y - 1/2, -z + 1/2), each within a distance of 2.98 (2) Å. The crystal packing is stabilized by C—H···O and C—H···F hydrogen bonds and a π–π intermolecular interaction. Atoms C2 and C7 act as donors to O1 (-x + 1/2, y - 1/2, -z + 1/2) and F2 (-x + 3/2, y - 1/2, -z + 1/2) generating a chain running along the a axis. Atom C18 acts as a donor to O2 (-x + 1, -y + 1, -z) generating a centrosymmetric dimer of R22(16) ring centred at (1/2, 1/2, 0). An intermolecular π–π interaction is observed between the symmetry related six-membered ring, Cg···Cgi [symmetry code: (i) -x, 1 - y, -z; Cg is the centroid of the C8—C13 ring], with the centroid-centroid separation of 3.783 (1)Å and with the slippage of 1.191 Å.

Experimental

The title compound was obtained by adopting our earlier method (Aridoss et al. 2007a) with slight modification. To a solution of 2,6-bis(3-fluorophenyl)- piperidin-4-one (1 equiv.) and NEt3 (1.5 equiv.) in freshly distilled benzene, chloroacetyl chloride (1 equiv.) in benzene was added drop wise. Stirring was continued until the completion of reaction. Later, it was poured into water and extracted with ethyl acetate. The combined organic extract was then washed well with a 3% sodium bicarbonate solution, brined and dried over anhydrous sodium sulfate. This, upon evaporation and subsequent recrystallization of the title compound in distilled ethanol afforded fine crystals suitable for X-ray diffraction study.

Refinement

All H-atoms were positioned geometrically and refined using a riding model, with d(C—H) = 0.93 Å, Uiso = 1.2Ueq (C) for aromatic, 0.97 Å, Uiso = 1.2Ueq (C) for CH2 and 0.98 Å, Uiso = 1.2Ueq (C) for CH atoms.

Figures

Fig. 1.
The molecular structure of the title compound(I), showing 30% probability displacement ellipsoids.
Fig. 2.
The molecular packing of (I), viewed approximately along the b axis, showing C—H···O and C—H···F hydrogen bonds, drawn as thick dashed lines, and π–π intermolecular ...

Crystal data

C19H16ClF2NO2F(000) = 752
Mr = 363.78Dx = 1.471 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 2558 reflections
a = 10.7026 (8) Åθ = 2.0–28.1°
b = 8.2017 (6) ŵ = 0.27 mm1
c = 19.0447 (15) ÅT = 293 K
β = 100.629 (1)°Block, colorless
V = 1643.1 (2) Å30.29 × 0.25 × 0.22 mm
Z = 4

Data collection

Bruker SMART APEX diffractometer3515 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.018
graphiteθmax = 28.1°, θmin = 2.0°
ω scansh = −14→13
18143 measured reflectionsk = −10→10
3875 independent reflectionsl = −25→24

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)] = 0.039Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.111H-atom parameters constrained
S = 1.03w = 1/[σ2(Fo2) + (0.0604P)2 + 0.4707P] where P = (Fo2 + 2Fc2)/3
3875 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = −0.35 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
C10.19220 (11)0.60188 (15)0.12209 (7)0.0342 (3)
H10.16330.49070.12910.041*
C20.14537 (12)0.70807 (17)0.17787 (7)0.0391 (3)
H2A0.05320.71010.16800.047*
H2B0.17250.66010.22480.047*
C30.19437 (12)0.87902 (16)0.17849 (6)0.0355 (3)
C40.31441 (12)0.89729 (15)0.14859 (7)0.0366 (3)
H4A0.36050.99170.17050.044*
H4B0.29140.91840.09770.044*
C50.40356 (11)0.74875 (14)0.15997 (6)0.0315 (2)
H50.43930.74000.21110.038*
C60.38663 (12)0.44552 (15)0.14846 (6)0.0342 (3)
C70.52903 (13)0.44165 (16)0.17627 (8)0.0437 (3)
H7A0.54780.49800.22180.052*
H7B0.57220.49860.14300.052*
C80.14016 (11)0.64593 (15)0.04440 (7)0.0359 (3)
C90.18650 (13)0.56233 (18)−0.00921 (8)0.0438 (3)
H90.24970.48390.00240.053*
C100.13769 (15)0.5973 (2)−0.07922 (8)0.0497 (3)
C110.04478 (16)0.7120 (2)−0.09979 (8)0.0530 (4)
H110.01470.7346−0.14780.064*
C12−0.00203 (16)0.7923 (2)−0.04692 (9)0.0548 (4)
H12−0.06590.8695−0.05930.066*
C130.04442 (14)0.76014 (18)0.02456 (8)0.0459 (3)
H130.01120.81560.05960.055*
C140.51171 (11)0.78384 (15)0.12008 (7)0.0330 (2)
C150.62680 (12)0.84067 (18)0.15766 (8)0.0420 (3)
H150.64150.84800.20720.050*
C160.71890 (13)0.8861 (2)0.11948 (9)0.0528 (4)
C170.70255 (15)0.8775 (2)0.04699 (10)0.0558 (4)
H170.76670.90980.02310.067*
C180.58841 (15)0.8196 (2)0.01009 (8)0.0507 (4)
H180.57510.8119−0.03940.061*
C190.49307 (14)0.77279 (17)0.04628 (7)0.0416 (3)
H190.41630.73380.02090.050*
N10.33311 (9)0.59708 (12)0.13708 (5)0.0316 (2)
O10.14246 (10)0.99449 (13)0.20033 (6)0.0477 (2)
O20.32477 (10)0.32101 (12)0.13649 (6)0.0467 (2)
F10.18216 (12)0.51239 (17)−0.13076 (6)0.0785 (3)
F20.83117 (10)0.9428 (2)0.15588 (7)0.0907 (4)
Cl10.58658 (4)0.24037 (5)0.18722 (3)0.06261 (15)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
C10.0292 (5)0.0319 (6)0.0411 (6)−0.0020 (4)0.0055 (5)0.0025 (5)
C20.0355 (6)0.0431 (7)0.0411 (6)0.0005 (5)0.0129 (5)0.0045 (5)
C30.0356 (6)0.0407 (7)0.0299 (5)0.0040 (5)0.0056 (4)−0.0001 (5)
C40.0389 (6)0.0302 (6)0.0422 (6)−0.0006 (5)0.0118 (5)−0.0019 (5)
C50.0318 (6)0.0319 (6)0.0309 (5)−0.0024 (4)0.0060 (4)−0.0012 (4)
C60.0375 (6)0.0327 (6)0.0328 (5)0.0023 (5)0.0075 (5)0.0006 (4)
C70.0392 (7)0.0337 (6)0.0572 (8)0.0069 (5)0.0060 (6)0.0044 (6)
C80.0310 (6)0.0328 (6)0.0420 (6)−0.0048 (5)0.0020 (5)−0.0005 (5)
C90.0399 (7)0.0435 (7)0.0458 (7)0.0008 (5)0.0021 (5)−0.0040 (6)
C100.0496 (8)0.0558 (9)0.0434 (7)−0.0096 (7)0.0075 (6)−0.0066 (6)
C110.0545 (8)0.0570 (9)0.0425 (7)−0.0111 (7)−0.0043 (6)0.0087 (7)
C120.0507 (8)0.0511 (8)0.0571 (9)0.0078 (7)−0.0045 (7)0.0090 (7)
C130.0414 (7)0.0447 (8)0.0495 (8)0.0051 (6)0.0026 (6)0.0006 (6)
C140.0319 (6)0.0297 (5)0.0383 (6)0.0006 (4)0.0091 (5)0.0008 (4)
C150.0356 (6)0.0450 (7)0.0443 (7)−0.0028 (5)0.0046 (5)0.0046 (6)
C160.0303 (6)0.0584 (9)0.0685 (10)−0.0043 (6)0.0056 (6)0.0149 (7)
C170.0423 (8)0.0624 (10)0.0686 (10)0.0073 (7)0.0261 (7)0.0195 (8)
C180.0588 (9)0.0532 (9)0.0451 (7)0.0056 (7)0.0227 (7)0.0028 (6)
C190.0437 (7)0.0433 (7)0.0388 (6)−0.0024 (5)0.0104 (5)−0.0027 (5)
N10.0294 (5)0.0295 (5)0.0353 (5)−0.0005 (4)0.0041 (4)0.0020 (4)
O10.0472 (5)0.0474 (6)0.0510 (6)0.0082 (4)0.0157 (4)−0.0071 (4)
O20.0474 (5)0.0311 (5)0.0601 (6)−0.0014 (4)0.0060 (4)−0.0032 (4)
F10.0865 (8)0.0996 (9)0.0501 (6)0.0098 (7)0.0145 (5)−0.0162 (6)
F20.0411 (5)0.1322 (12)0.0927 (8)−0.0331 (6)−0.0035 (5)0.0304 (8)
Cl10.0550 (2)0.0405 (2)0.0879 (3)0.01621 (16)0.0017 (2)0.00367 (18)

Geometric parameters (Å, °)

C1—N11.4827 (15)C8—C91.3948 (19)
C1—C81.5251 (17)C9—C101.370 (2)
C1—C21.5279 (18)C9—H90.9300
C1—H10.9800C10—F11.3590 (19)
C2—C31.4963 (19)C10—C111.373 (2)
C2—H2A0.9700C11—C121.373 (3)
C2—H2B0.9700C11—H110.9300
C3—O11.2099 (16)C12—C131.386 (2)
C3—C41.5056 (17)C12—H120.9300
C4—C51.5379 (17)C13—H130.9300
C4—H4A0.9700C14—C191.3857 (18)
C4—H4B0.9700C14—C151.3861 (18)
C5—N11.4781 (15)C15—C161.380 (2)
C5—C141.5246 (16)C15—H150.9300
C5—H50.9800C16—F21.3542 (18)
C6—O21.2154 (16)C16—C171.361 (2)
C6—N11.3691 (15)C17—C181.376 (2)
C6—C71.5187 (18)C17—H170.9300
C7—Cl11.7609 (14)C18—C191.387 (2)
C7—H7A0.9700C18—H180.9300
C7—H7B0.9700C19—H190.9300
C8—C131.3883 (19)
N1—C1—C8111.69 (10)C9—C8—C1118.56 (12)
N1—C1—C2109.49 (10)C10—C9—C8119.11 (14)
C8—C1—C2115.56 (11)C10—C9—H9120.4
N1—C1—H1106.5C8—C9—H9120.4
C8—C1—H1106.5F1—C10—C9118.32 (15)
C2—C1—H1106.5F1—C10—C11118.48 (14)
C3—C2—C1112.34 (10)C9—C10—C11123.19 (15)
C3—C2—H2A109.1C12—C11—C10117.56 (14)
C1—C2—H2A109.1C12—C11—H11121.2
C3—C2—H2B109.1C10—C11—H11121.2
C1—C2—H2B109.1C11—C12—C13121.06 (15)
H2A—C2—H2B107.9C11—C12—H12119.5
O1—C3—C2123.62 (12)C13—C12—H12119.5
O1—C3—C4122.01 (12)C12—C13—C8120.59 (15)
C2—C3—C4114.36 (10)C12—C13—H13119.7
C3—C4—C5114.73 (10)C8—C13—H13119.7
C3—C4—H4A108.6C19—C14—C15119.59 (12)
C5—C4—H4A108.6C19—C14—C5120.83 (11)
C3—C4—H4B108.6C15—C14—C5119.36 (11)
C5—C4—H4B108.6C16—C15—C14118.16 (13)
H4A—C4—H4B107.6C16—C15—H15120.9
N1—C5—C14113.88 (9)C14—C15—H15120.9
N1—C5—C4110.83 (10)F2—C16—C17118.22 (14)
C14—C5—C4106.77 (9)F2—C16—C15118.41 (15)
N1—C5—H5108.4C17—C16—C15123.37 (14)
C14—C5—H5108.4C16—C17—C18118.13 (13)
C4—C5—H5108.4C16—C17—H17120.9
O2—C6—N1122.39 (11)C18—C17—H17120.9
O2—C6—C7121.65 (11)C17—C18—C19120.47 (14)
N1—C6—C7115.96 (11)C17—C18—H18119.8
C6—C7—Cl1111.56 (10)C19—C18—H18119.8
C6—C7—H7A109.3C14—C19—C18120.29 (14)
Cl1—C7—H7A109.3C14—C19—H19119.9
C6—C7—H7B109.3C18—C19—H19119.9
Cl1—C7—H7B109.3C6—N1—C5122.80 (10)
H7A—C7—H7B108.0C6—N1—C1115.82 (10)
C13—C8—C9118.47 (13)C5—N1—C1118.67 (9)
C13—C8—C1122.89 (12)
N1—C1—C2—C359.23 (13)C4—C5—C14—C19−75.31 (14)
C8—C1—C2—C3−67.92 (14)N1—C5—C14—C15−138.10 (12)
C1—C2—C3—O1156.26 (12)C4—C5—C14—C1599.24 (13)
C1—C2—C3—C4−23.06 (15)C19—C14—C15—C160.6 (2)
O1—C3—C4—C5149.28 (12)C5—C14—C15—C16−173.98 (13)
C2—C3—C4—C5−31.38 (15)C14—C15—C16—F2179.52 (14)
C3—C4—C5—N150.02 (14)C14—C15—C16—C17−0.2 (2)
C3—C4—C5—C14174.56 (10)F2—C16—C17—C18179.94 (16)
O2—C6—C7—Cl10.30 (17)C15—C16—C17—C18−0.4 (3)
N1—C6—C7—Cl1−179.00 (9)C16—C17—C18—C190.4 (2)
N1—C1—C8—C13−134.11 (13)C15—C14—C19—C18−0.6 (2)
C2—C1—C8—C13−8.06 (18)C5—C14—C19—C18173.95 (13)
N1—C1—C8—C949.02 (15)C17—C18—C19—C140.0 (2)
C2—C1—C8—C9175.06 (11)O2—C6—N1—C5171.94 (12)
C13—C8—C9—C101.0 (2)C7—C6—N1—C5−8.77 (16)
C1—C8—C9—C10178.01 (12)O2—C6—N1—C110.87 (17)
C8—C9—C10—F1−178.72 (13)C7—C6—N1—C1−169.84 (11)
C8—C9—C10—C110.3 (2)C14—C5—N1—C666.79 (14)
F1—C10—C11—C12177.74 (15)C4—C5—N1—C6−172.80 (10)
C9—C10—C11—C12−1.2 (2)C14—C5—N1—C1−132.65 (11)
C10—C11—C12—C131.0 (3)C4—C5—N1—C1−12.24 (14)
C11—C12—C13—C80.3 (3)C8—C1—N1—C6−109.19 (12)
C9—C8—C13—C12−1.3 (2)C2—C1—N1—C6121.50 (11)
C1—C8—C13—C12−178.13 (13)C8—C1—N1—C588.92 (13)
N1—C5—C14—C1947.35 (16)C2—C1—N1—C5−40.39 (14)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C2—H2B···O1i0.972.603.415 (2)142
C7—H7A···F2ii0.972.493.270 (2)137
C18—H18···O2iii0.932.553.308 (2)139

Symmetry codes: (i) −x+1/2, y−1/2, −z+1/2; (ii) −x+3/2, y−1/2, −z+1/2; (iii) −x+1, −y+1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BG2281).

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