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Acta Crystallogr Sect E Struct Rep Online. 2009 August 1; 65(Pt 8): o1975.
Published online 2009 July 25. doi:  10.1107/S1600536809028037
PMCID: PMC2977502

1-Benzoyl-c-3,t-3-dimethyl-r-2,c-6-diphenyl­piperidin-4-one

Abstract

In the title compound, C26H25NO2, the piperidine ring adopts a distorted boat conformation. The three phenyl rings form dihedral angles of 67.58 (8), 59.82 (8) and 86.41 (8)° with the best plane through the piperidine ring. The crystal packing is governed by inter­molecular C—H(...)O inter­actions.

Related literature

For the biological activity of piperidine derivatives, see: Dimmock et al. (2001 [triangle]); Perumal et al. (2001 [triangle]). For hydrogen-bond motifs, see: Bernstein et al. (1995 [triangle]). For puckering and asymmetry parameters, see: Cremer & Pople (1975 [triangle]); Nardelli (1983 [triangle]).

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Object name is e-65-o1975-scheme1.jpg

Experimental

Crystal data

  • C26H25NO2
  • M r = 383.47
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o1975-efi1.jpg
  • a = 10.8540 (9) Å
  • b = 17.8050 (17) Å
  • c = 10.8853 (10) Å
  • β = 94.987 (3)°
  • V = 2095.7 (3) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.08 mm−1
  • T = 293 K
  • 0.30 × 0.25 × 0.20 mm

Data collection

  • Bruker Kappa APEXII area-detector diffractometer
  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001 [triangle]) T min = 0.977, T max = 0.985
  • 27356 measured reflections
  • 6189 independent reflections
  • 3897 reflections with I > 2σ(I)
  • R int = 0.038

Refinement

  • R[F 2 > 2σ(F 2)] = 0.050
  • wR(F 2) = 0.152
  • S = 0.98
  • 6189 reflections
  • 265 parameters
  • H-atom parameters constrained
  • Δρmax = 0.24 e Å−3
  • Δρmin = −0.17 e Å−3

Data collection: APEX2 (Bruker, 2004 [triangle]); cell refinement: SAINT (Bruker, 2004 [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: ORTEP-3 (Farrugia, 1997 [triangle]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 [triangle]).

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809028037/bt2990sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809028037/bt2990Isup2.hkl

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

Acknowledgments

SA thanks Dr Babu Varghese, SAIF, IIT–Madras, India, for his help with the data collection.

supplementary crystallographic information

Comment

Piperidones are the important group of heterocyclic compounds in the field of medicinal chemistry due to their biological activities, including cytotoxic and anticancer properties (Dimmock et al., 2001). They were also reported to possess analgesic, anti-inflammatory, central nervous system (CNS), local anaesthetic, anticancer and antimicrobial activities (Perumal et al., 2001). In view of these importance and to ascertain the molecular conformation, crystallographic study of the title compound has been carried out.

The ORTEP diagram of the title compound is shown in Fig.1. The piperidine ring adopts distorted boat conformation. The puckering parameters (Cremer & Pople, 1975) and the asymmetry parameters (Nardelli, 1983) for this ring are q2 = 0.636 (2) Å, q3 = 0.104 (2) Å, π = 282.8 (1)° and Δs(C3) =Δs(C6)= 18.6 (1)°. The sum of the angles at N1 (359.7°) is in accrdance with sp2 hybridization. The three phenyl rings are twisted away from the best plane of the pyridine ring by 67.58 (8)°, 59.82 (8)° and 86.41 (8)° respectively.

The crystal packing is controlled by C—H···O types of intra and intermolecular interactions in addition to van der Waals forces. Atom C2 at (x, y, z) donates a proton to O1 x, -y + 1/2, z + 1/2, which forms a C(5) (Bernstein, et al., 1995) zigzag chain running along c axis. The combination of C20—H20A···O1 and C20—H20B···O2 intermolecular interactions forms a dimer chain running along c axis shown in Fig. 2.

Experimental

A mixture of c-3,t-3-dimethyl-r-2,c-6-diphenylpiperidin-4-one (1.4 g, 5 mmol), benzoyl chloride (1.2 ml, 10 mmol) and triethylamine (2 ml, 14.4 mmol) in anhydrous benzene (20 ml) was stirred at room temperature for 7 h. The precipitated ammonium salt was washed with water (4x10ml). The resulting pasty mass was purified and crystallized from benzene and pet-ether (60–80°C) in the ratio of 95: 5.

Refinement

All H atoms were positioned geometrically (C—H=0.93–0.98 Å) and allowed to ride on their parent atoms, with 1.5Ueq(C) for methyl H and 1.2 Ueq(C) for other H atoms.

Figures

Fig. 1.
Perspective view of the molecule showing displacement ellipsoids at 50% probability level. The H atoms are omitted for clarity.
Fig. 2.
The crystal packing viewed down a axis. H atoms not involved in hydrogen bonding have been omitted for clarity.

Crystal data

C26H25NO2F(000) = 816
Mr = 383.47Dx = 1.215 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 5746 reflections
a = 10.8540 (9) Åθ = 1.9–30.4°
b = 17.8050 (17) ŵ = 0.08 mm1
c = 10.8853 (10) ÅT = 293 K
β = 94.987 (3)°Block, colorless
V = 2095.7 (3) Å30.30 × 0.25 × 0.20 mm
Z = 4

Data collection

Bruker Kappa APEXII area-detector diffractometer6189 independent reflections
Radiation source: fine-focus sealed tube3897 reflections with I > 2σ(I)
graphiteRint = 0.038
ω and [var phi] scansθmax = 30.4°, θmin = 1.9°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)h = −15→13
Tmin = 0.977, Tmax = 0.985k = −25→25
27356 measured reflectionsl = −15→15

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.050H-atom parameters constrained
wR(F2) = 0.152w = 1/[σ2(Fo2) + (0.0728P)2 + 0.3353P] where P = (Fo2 + 2Fc2)/3
S = 0.98(Δ/σ)max = 0.011
6189 reflectionsΔρmax = 0.24 e Å3
265 parametersΔρmin = −0.17 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0078 (16)

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
O10.14493 (11)0.19520 (7)0.50443 (9)0.0560 (3)
O20.41301 (12)0.16165 (9)1.02065 (10)0.0722 (4)
N10.17515 (10)0.16380 (6)0.70591 (9)0.0338 (2)
C20.12064 (12)0.15019 (8)0.82403 (11)0.0361 (3)
H20.08810.19800.85200.043*
C30.21997 (14)0.12271 (9)0.92293 (12)0.0466 (4)
H3A0.18860.12941.00300.056*
H3B0.23130.06920.91130.056*
C40.34508 (15)0.15986 (10)0.92630 (13)0.0493 (4)
C50.38114 (14)0.19299 (9)0.80660 (13)0.0446 (3)
C60.30890 (12)0.15316 (7)0.69712 (11)0.0362 (3)
H60.32820.18090.62350.043*
C70.10627 (13)0.19291 (8)0.60735 (11)0.0373 (3)
C8−0.01836 (13)0.22524 (8)0.62390 (11)0.0376 (3)
C9−0.12156 (16)0.19732 (9)0.55574 (16)0.0543 (4)
H9−0.11490.15500.50670.065*
C10−0.23461 (17)0.23218 (11)0.5604 (2)0.0681 (5)
H10−0.30400.21250.51550.082*
C11−0.24602 (16)0.29517 (10)0.62980 (18)0.0600 (4)
H11−0.32230.31870.63120.072*
C12−0.14437 (17)0.32334 (10)0.69727 (17)0.0588 (4)
H12−0.15160.36640.74450.071*
C13−0.03124 (15)0.28842 (9)0.69574 (15)0.0507 (4)
H130.03700.30750.74330.061*
C140.01468 (13)0.09444 (8)0.80976 (12)0.0385 (3)
C150.01631 (15)0.03311 (8)0.73135 (15)0.0485 (4)
H150.08320.02590.68480.058*
C16−0.08083 (17)−0.01740 (10)0.72184 (18)0.0608 (5)
H16−0.0791−0.05820.66880.073*
C17−0.18017 (18)−0.00735 (12)0.7908 (2)0.0699 (5)
H17−0.2455−0.04130.78440.084*
C18−0.18221 (18)0.05259 (13)0.8683 (2)0.0724 (6)
H18−0.24900.05920.91520.087*
C19−0.08585 (15)0.10376 (10)0.87796 (15)0.0561 (4)
H19−0.08880.14470.93070.067*
C200.34155 (16)0.27631 (9)0.80821 (15)0.0539 (4)
H20A0.25500.27940.81960.081*
H20B0.35690.29950.73140.081*
H20C0.38820.30180.87470.081*
C210.52053 (15)0.19025 (12)0.79462 (18)0.0646 (5)
H21A0.56340.21490.86420.097*
H21B0.53860.21530.72020.097*
H21C0.54700.13890.79200.097*
C220.34321 (13)0.07146 (8)0.67344 (13)0.0397 (3)
C230.40686 (15)0.02446 (10)0.75922 (15)0.0532 (4)
H230.43000.04240.83810.064*
C240.43630 (17)−0.04821 (10)0.72953 (19)0.0638 (5)
H240.4789−0.07870.78820.077*
C250.40313 (18)−0.07557 (10)0.6143 (2)0.0700 (5)
H250.4234−0.12460.59430.084*
C260.33977 (17)−0.03070 (10)0.52792 (18)0.0627 (5)
H260.3162−0.04950.44970.075*
C270.31101 (14)0.04226 (9)0.55720 (14)0.0475 (4)
H270.26910.07240.49760.057*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0589 (7)0.0747 (8)0.0352 (5)0.0155 (6)0.0096 (5)0.0121 (5)
O20.0575 (8)0.1115 (11)0.0444 (6)−0.0127 (7)−0.0138 (5)−0.0013 (6)
N10.0348 (6)0.0364 (6)0.0304 (5)−0.0024 (4)0.0035 (4)0.0021 (4)
C20.0398 (7)0.0379 (7)0.0308 (6)−0.0046 (6)0.0045 (5)0.0026 (5)
C30.0469 (9)0.0608 (9)0.0314 (6)−0.0062 (7)−0.0002 (6)0.0079 (6)
C40.0465 (9)0.0623 (10)0.0377 (7)−0.0050 (7)−0.0046 (6)−0.0025 (6)
C50.0382 (8)0.0535 (8)0.0418 (7)−0.0107 (6)0.0023 (6)−0.0053 (6)
C60.0346 (7)0.0400 (7)0.0342 (6)−0.0031 (5)0.0044 (5)0.0009 (5)
C70.0424 (8)0.0365 (7)0.0329 (6)−0.0008 (6)0.0025 (5)0.0033 (5)
C80.0400 (8)0.0384 (7)0.0341 (6)0.0001 (6)0.0012 (5)0.0054 (5)
C90.0520 (10)0.0482 (9)0.0602 (9)0.0012 (7)−0.0090 (7)−0.0065 (7)
C100.0455 (10)0.0635 (11)0.0914 (13)−0.0029 (8)−0.0171 (9)−0.0044 (10)
C110.0421 (10)0.0613 (11)0.0772 (11)0.0092 (8)0.0096 (8)0.0086 (9)
C120.0585 (11)0.0559 (10)0.0623 (10)0.0107 (8)0.0065 (8)−0.0072 (8)
C130.0465 (9)0.0514 (9)0.0530 (8)0.0019 (7)−0.0029 (7)−0.0096 (7)
C140.0380 (8)0.0398 (7)0.0372 (6)−0.0028 (6)−0.0002 (5)0.0102 (5)
C150.0461 (9)0.0402 (8)0.0588 (9)−0.0051 (6)0.0020 (7)0.0019 (6)
C160.0605 (11)0.0441 (9)0.0748 (11)−0.0121 (8)−0.0106 (9)0.0065 (8)
C170.0543 (11)0.0667 (12)0.0860 (13)−0.0249 (9)−0.0094 (9)0.0264 (10)
C180.0478 (11)0.0892 (15)0.0825 (13)−0.0161 (10)0.0185 (9)0.0165 (11)
C190.0482 (10)0.0659 (11)0.0556 (9)−0.0082 (8)0.0125 (7)0.0015 (8)
C200.0578 (10)0.0517 (9)0.0534 (9)−0.0181 (8)0.0115 (7)−0.0115 (7)
C210.0408 (10)0.0849 (13)0.0679 (11)−0.0175 (9)0.0028 (8)−0.0122 (9)
C220.0322 (7)0.0419 (7)0.0450 (7)−0.0006 (6)0.0034 (5)0.0021 (6)
C230.0476 (9)0.0557 (9)0.0546 (9)0.0042 (7)−0.0047 (7)0.0055 (7)
C240.0506 (10)0.0528 (10)0.0855 (13)0.0092 (8)−0.0085 (9)0.0137 (9)
C250.0571 (12)0.0432 (9)0.1068 (15)0.0095 (8)−0.0094 (10)−0.0086 (10)
C260.0609 (11)0.0520 (10)0.0728 (11)0.0076 (8)−0.0074 (9)−0.0174 (8)
C270.0454 (9)0.0468 (8)0.0493 (8)0.0055 (7)−0.0021 (6)−0.0041 (6)

Geometric parameters (Å, °)

O1—C71.2307 (16)C14—C191.382 (2)
O2—C41.2115 (17)C14—C151.387 (2)
N1—C71.3561 (16)C15—C161.383 (2)
N1—C61.4754 (17)C15—H150.9300
N1—C21.4813 (15)C16—C171.378 (3)
C2—C141.5170 (19)C16—H160.9300
C2—C31.5359 (19)C17—C181.362 (3)
C2—H20.9800C17—H170.9300
C3—C41.508 (2)C18—C191.384 (3)
C3—H3A0.9700C18—H180.9300
C3—H3B0.9700C19—H190.9300
C4—C51.513 (2)C20—H20A0.9600
C5—C211.531 (2)C20—H20B0.9600
C5—C61.5412 (19)C20—H20C0.9600
C5—C201.545 (2)C21—H21A0.9600
C6—C221.529 (2)C21—H21B0.9600
C6—H60.9800C21—H21C0.9600
C7—C81.495 (2)C22—C271.384 (2)
C8—C91.381 (2)C22—C231.392 (2)
C8—C131.384 (2)C23—C241.378 (2)
C9—C101.380 (3)C23—H230.9300
C9—H90.9300C24—C251.364 (3)
C10—C111.364 (3)C24—H240.9300
C10—H100.9300C25—C261.372 (3)
C11—C121.367 (3)C25—H250.9300
C11—H110.9300C26—C271.380 (2)
C12—C131.378 (2)C26—H260.9300
C12—H120.9300C27—H270.9300
C13—H130.9300
C7—N1—C6118.40 (10)C8—C13—H13119.7
C7—N1—C2120.99 (11)C19—C14—C15118.55 (14)
C6—N1—C2120.31 (10)C19—C14—C2119.56 (13)
N1—C2—C14112.00 (10)C15—C14—C2121.88 (13)
N1—C2—C3110.59 (11)C16—C15—C14120.51 (16)
C14—C2—C3110.06 (11)C16—C15—H15119.7
N1—C2—H2108.0C14—C15—H15119.7
C14—C2—H2108.0C17—C16—C15120.16 (18)
C3—C2—H2108.0C17—C16—H16119.9
C4—C3—C2116.94 (12)C15—C16—H16119.9
C4—C3—H3A108.1C18—C17—C16119.66 (17)
C2—C3—H3A108.1C18—C17—H17120.2
C4—C3—H3B108.1C16—C17—H17120.2
C2—C3—H3B108.1C17—C18—C19120.68 (18)
H3A—C3—H3B107.3C17—C18—H18119.7
O2—C4—C3120.83 (14)C19—C18—H18119.7
O2—C4—C5122.41 (15)C14—C19—C18120.43 (17)
C3—C4—C5116.74 (12)C14—C19—H19119.8
C4—C5—C21113.12 (14)C18—C19—H19119.8
C4—C5—C6109.53 (12)C5—C20—H20A109.5
C21—C5—C6111.08 (12)C5—C20—H20B109.5
C4—C5—C20105.76 (12)H20A—C20—H20B109.5
C21—C5—C20108.03 (13)C5—C20—H20C109.5
C6—C5—C20109.10 (12)H20A—C20—H20C109.5
N1—C6—C22112.86 (11)H20B—C20—H20C109.5
N1—C6—C5109.16 (10)C5—C21—H21A109.5
C22—C6—C5116.95 (12)C5—C21—H21B109.5
N1—C6—H6105.6H21A—C21—H21B109.5
C22—C6—H6105.6C5—C21—H21C109.5
C5—C6—H6105.6H21A—C21—H21C109.5
O1—C7—N1121.65 (13)H21B—C21—H21C109.5
O1—C7—C8118.71 (12)C27—C22—C23117.29 (14)
N1—C7—C8119.61 (11)C27—C22—C6117.74 (12)
C9—C8—C13118.61 (14)C23—C22—C6124.95 (13)
C9—C8—C7119.78 (13)C24—C23—C22121.26 (16)
C13—C8—C7121.19 (13)C24—C23—H23119.4
C10—C9—C8120.05 (16)C22—C23—H23119.4
C10—C9—H9120.0C25—C24—C23120.19 (16)
C8—C9—H9120.0C25—C24—H24119.9
C11—C10—C9120.93 (17)C23—C24—H24119.9
C11—C10—H10119.5C24—C25—C26119.90 (17)
C9—C10—H10119.5C24—C25—H25120.0
C10—C11—C12119.45 (16)C26—C25—H25120.0
C10—C11—H11120.3C25—C26—C27119.99 (17)
C12—C11—H11120.3C25—C26—H26120.0
C11—C12—C13120.44 (16)C27—C26—H26120.0
C11—C12—H12119.8C26—C27—C22121.36 (15)
C13—C12—H12119.8C26—C27—H27119.3
C12—C13—C8120.50 (15)C22—C27—H27119.3
C12—C13—H13119.7
C7—N1—C2—C1461.05 (16)C13—C8—C9—C10−0.2 (2)
C6—N1—C2—C14−125.24 (12)C7—C8—C9—C10−172.85 (15)
C7—N1—C2—C3−175.79 (12)C8—C9—C10—C111.3 (3)
C6—N1—C2—C3−2.08 (16)C9—C10—C11—C12−1.1 (3)
N1—C2—C3—C440.28 (18)C10—C11—C12—C13−0.2 (3)
C14—C2—C3—C4164.56 (13)C11—C12—C13—C81.3 (3)
C2—C3—C4—O2154.70 (16)C9—C8—C13—C12−1.1 (2)
C2—C3—C4—C5−26.3 (2)C7—C8—C13—C12171.44 (14)
O2—C4—C5—C2130.2 (2)N1—C2—C14—C19−144.35 (13)
C3—C4—C5—C21−148.72 (15)C3—C2—C14—C1992.20 (16)
O2—C4—C5—C6154.74 (16)N1—C2—C14—C1536.78 (18)
C3—C4—C5—C6−24.22 (19)C3—C2—C14—C15−86.67 (15)
O2—C4—C5—C20−87.8 (2)C19—C14—C15—C160.1 (2)
C3—C4—C5—C2093.23 (16)C2—C14—C15—C16178.96 (13)
C7—N1—C6—C22−102.18 (13)C14—C15—C16—C17−0.3 (2)
C2—N1—C6—C2283.95 (14)C15—C16—C17—C180.0 (3)
C7—N1—C6—C5125.98 (13)C16—C17—C18—C190.4 (3)
C2—N1—C6—C5−47.89 (15)C15—C14—C19—C180.3 (2)
C4—C5—C6—N159.99 (15)C2—C14—C19—C18−178.58 (16)
C21—C5—C6—N1−174.33 (13)C17—C18—C19—C14−0.6 (3)
C20—C5—C6—N1−55.34 (14)N1—C6—C22—C2772.51 (15)
C4—C5—C6—C22−69.65 (16)C5—C6—C22—C27−159.62 (13)
C21—C5—C6—C2256.03 (17)N1—C6—C22—C23−108.93 (15)
C20—C5—C6—C22175.02 (11)C5—C6—C22—C2318.9 (2)
C6—N1—C7—O116.05 (19)C27—C22—C23—C24−0.1 (2)
C2—N1—C7—O1−170.12 (13)C6—C22—C23—C24−178.70 (15)
C6—N1—C7—C8−162.10 (11)C22—C23—C24—C250.0 (3)
C2—N1—C7—C811.73 (18)C23—C24—C25—C26−0.3 (3)
O1—C7—C8—C959.09 (19)C24—C25—C26—C270.8 (3)
N1—C7—C8—C9−122.69 (15)C25—C26—C27—C22−1.0 (3)
O1—C7—C8—C13−113.39 (16)C23—C22—C27—C260.6 (2)
N1—C7—C8—C1364.83 (18)C6—C22—C27—C26179.29 (15)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
C6—H6···O10.982.292.7346 (17)106
C2—H2···O1i0.982.563.3784 (17)141
C20—H20A···O1i0.962.473.1885 (19)132
C20—H20B···O2ii0.962.523.470 (2)170

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: BT2990).

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