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r-2,c-6-Di­phenyl­piperidine

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and bDepartment of Chemistry, Government Arts College (Autonomous), Coimbatore 641 018, India
*Correspondence e-mail: mnpsy2004@yahoo.com

(Received 1 July 2013; accepted 23 July 2013; online 3 August 2013)

In the title compound, C17H19N, the piperidine ring adopts a chair conformation. The phenyl rings substituted at the 2- and 6-positions of the piperidine ring subtend dihedral angles of 81.04 (7) and 81.10 (7)° with the best plane of the piperidine ring. The crystal packing features C—H⋯π inter­actions.

Related literature

For the biological activity of piperidine derivatives, see: Aridoss et al. (2009[Aridoss, G., Parthiban, P., Ramachandran, R., Prakash, M., Kabilan, S. & Jeong, Y. T. (2009). Eur. J. Med. Chem. 44, 577-592.]); Boehringer & Söhne GmbH (1961[Boehringer & Söhne GmbH (1961). Chem. Abstr. 55, 24796g.]); Jain et al. (2005[Jain, R., Chen, D., White, R. J., Patel, D. V. & Yuan, Z. (2005). Curr. Med. Chem. 12, 1607-1627.]); Kubota et al. (1998[Kubota, H., Fujii, M., Ikeda, K., Takeuchi, M., Shibanuma, T. & Isomura, Y. (1998). Chem. Pharm. Bull. 46, 351-354.]); Mobio et al. (1989[Mobio, I. G., Soldatenkov, A. T., Federov, V. O., Ageev, E. A., Sargeeva, N. D., Lin, S., Stashenko, E. E., Prostakov, N. S. & Andreeva, E. I. (1989). Khim. Farm. Zh. 23, 421-427.]); Rubiralta et al. (1991[Rubiralta, M., Giralt, E. & Diez, A. (1991). Piperidine: Structure, Preparation, Reactivity, and Synthetic Applications of Piperidine and its Derivatives, pp. 225-312. Amsterdam: Elsevier.]). For the synthesis of the title compound, see: Ponnuswamy et al. (2002[Ponnuswamy, S., Venkatraj, M., Jeyaraman, R., Suresh Kumar, M., Kumaran, D. & Ponnuswamy, M. N. (2002). Indian J. Chem. Sect. B, 41, 614-627.]). For puckering parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]). For asymmetry parameters, see: Nardelli (1983[Nardelli, M. (1983). Acta Cryst. C39, 1141-1142.]).

[Scheme 1]

Experimental

Crystal data
  • C17H19N

  • Mr = 237.33

  • Triclinic, [P \overline 1]

  • a = 5.6450 (9) Å

  • b = 11.2255 (17) Å

  • c = 11.5281 (17) Å

  • α = 73.911 (9)°

  • β = 89.898 (9)°

  • γ = 81.466 (9)°

  • V = 693.53 (18) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.07 mm−1

  • T = 293 K

  • 0.21 × 0.19 × 0.18 mm

Data collection
  • Bruker SMART APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.986, Tmax = 0.988

  • 9781 measured reflections

  • 2813 independent reflections

  • 2113 reflections with I > 2σ(I)

  • Rint = 0.032

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.125

  • S = 1.06

  • 2813 reflections

  • 167 parameters

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

  • Δρmax = 0.11 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the C13–C18 and C7–C12 rings, respectively.

D—H⋯A D—H H⋯A DA D—H⋯A
C3—H3ACg1i 0.97 3.00 3.719 (2) 132
C10—H10⋯Cg1ii 0.93 3.01 3.760 (2) 139
C16—H16⋯Cg2iii 0.93 3.03 3.799 (2) 141
Symmetry codes: (i) -x+2, -y+1, -z+2; (ii) -x+1, -y+2, -z+1; (iii) x, y-1, z.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SADABS and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Piperidines are valuable heterocyclic compounds found in natural substances and pharmaceutical products (Rubiralta et al., 1991; Jain et al., 2005; Kubota et al., 1998). Several 2,6-substituted piperidine derivatives were found to be useful as tranquilisers (Boehringer & Söhne GmbH, 1961) and possess a wide range of biological activities such as antiviral, antimalarial, antibacterial and antifungal activities (Aridoss et al., 2009, Mobio et al., 1989). In view of the above importance, the crystallographic study of the title compound has been carried out to establish its molecular structure.

The ORTEP plot of the molecule is shown in Fig. 1. The piperidine ring adopts a chair conformation with puckering parameters (Cremer & Pople, 1975) and asymmetry parameters (Nardelli, 1983): q2=0.0420 (15) Å, q3 = -0.5799 (15) Å, ϕ2 = 190 (2)° and Δs (N1& C4)= 0.75 (12)°. The phenyl rings at 2,6-positions of the piperidine ring occupy equatorial positions. The corresponding torsion angles are [C13—C2—C3—C4] -178.62 (11)° & [C4—C5—C6—C7] 177.89 (12)°, respectively. The dihedral angle between the two phenyl rings is 60.0 (7)°. The phenyl rings [C7—C12 & C13—C18] are twisted away from the best plane of the piperidine moiety by 81.04 (7)° & 81.10 (7)°, respectively. The molecules in the unit cell are connected by C—H ···π interactions (Fig. 2 & Table. 1; Cg1 is the centroid of the ring C13 to C18 and Cg2 is the centroid of the ring C7 to C12).

Related literature top

For the biological activity of piperidine derivatives, see: Aridoss et al. (2009); Boehringer & Söhne GmbH (1961); Jain et al. (2005); Kubota et al. (1998); Mobio et al. (1989); Rubiralta et al. (1991). For the synthesis of the title compound, see: Ponnuswamy et al. (2002). For puckering parameters, see: Cremer & Pople (1975). For asymmetry parameters, see: Nardelli (1983).

Experimental top

A mixture of piperidin-4-one (10 mM) and 80% hydrazine hydrate (3.1 ml) in diethylene glycol (100 ml) was heated on a steam bath for 2 hrs (Ponnuswamy et al., 2002). Potassium hydroxide pellets (2.8 g) were added to the mixture and the contents were allowed to reflux vigorously on a heating mantle for another 2 hrs and the reaction mixture was cooled. The product formed was filtered and recrystallized from ethanol.

Refinement top

All H atoms were found in a difference map. Nevertheless, those bonded to C were positioned geometrically (C–H = 0.93–0.98 Å) and allowed to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C). The H atom bonded to N was freely refined.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing the atomic numbering and displacement ellipsoids drawn at 30% probability level.
[Figure 2] Fig. 2. The crystal packing of the molecules viewed down a-axis.
r-2,c-6-Diphenylpiperidine top
Crystal data top
C17H19NZ = 2
Mr = 237.33F(000) = 256
Triclinic, P1Dx = 1.136 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.6450 (9) ÅCell parameters from 2113 reflections
b = 11.2255 (17) Åθ = 1.8–26.6°
c = 11.5281 (17) ŵ = 0.07 mm1
α = 73.911 (9)°T = 293 K
β = 89.898 (9)°Block, white
γ = 81.466 (9)°0.21 × 0.19 × 0.18 mm
V = 693.53 (18) Å3
Data collection top
Bruker SMART APEXII CCD
diffractometer
2813 independent reflections
Radiation source: fine-focus sealed tube2113 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.032
ω and ϕ scansθmax = 26.6°, θmin = 1.8°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 77
Tmin = 0.986, Tmax = 0.988k = 1314
9781 measured reflectionsl = 1414
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0582P)2 + 0.0755P]
where P = (Fo2 + 2Fc2)/3
2813 reflections(Δ/σ)max < 0.001
167 parametersΔρmax = 0.11 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C17H19Nγ = 81.466 (9)°
Mr = 237.33V = 693.53 (18) Å3
Triclinic, P1Z = 2
a = 5.6450 (9) ÅMo Kα radiation
b = 11.2255 (17) ŵ = 0.07 mm1
c = 11.5281 (17) ÅT = 293 K
α = 73.911 (9)°0.21 × 0.19 × 0.18 mm
β = 89.898 (9)°
Data collection top
Bruker SMART APEXII CCD
diffractometer
2813 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2113 reflections with I > 2σ(I)
Tmin = 0.986, Tmax = 0.988Rint = 0.032
9781 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.125H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.11 e Å3
2813 reflectionsΔρmin = 0.20 e Å3
167 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
C20.3110 (2)0.28559 (11)0.14071 (11)0.0526 (3)
H20.47180.28200.10840.063*
C30.1318 (3)0.28661 (13)0.04187 (13)0.0649 (4)
H3A0.02880.29270.07200.078*
H3B0.13750.35950.02640.078*
C40.1868 (3)0.16823 (14)0.00071 (13)0.0762 (4)
H4A0.33760.16800.03980.091*
H4B0.06190.16720.05650.091*
C50.2026 (3)0.05172 (13)0.10787 (13)0.0680 (4)
H5A0.25390.02220.08090.082*
H5B0.04520.04540.14070.082*
C60.3782 (2)0.05592 (11)0.20619 (12)0.0547 (3)
H60.53790.05800.17300.066*
C70.3915 (2)0.05597 (11)0.31576 (12)0.0525 (3)
C80.5902 (3)0.14804 (13)0.34202 (13)0.0643 (4)
H80.71970.14060.29190.077*
C90.5997 (3)0.25123 (14)0.44165 (15)0.0737 (4)
H90.73530.31230.45800.088*
C100.4108 (3)0.26438 (14)0.51663 (13)0.0699 (4)
H100.41760.33410.58350.084*
C110.2118 (3)0.17362 (14)0.49196 (15)0.0747 (4)
H110.08290.18160.54250.090*
C120.2023 (3)0.07085 (13)0.39271 (14)0.0685 (4)
H120.06620.01010.37690.082*
C130.2607 (2)0.39961 (11)0.18678 (11)0.0501 (3)
C140.0632 (3)0.41659 (13)0.25525 (13)0.0618 (4)
H140.04110.35770.27140.074*
C150.0190 (3)0.51912 (14)0.29970 (15)0.0735 (4)
H150.11400.52890.34590.088*
C160.1715 (3)0.60761 (14)0.27597 (15)0.0754 (4)
H160.14220.67680.30630.090*
C170.3659 (3)0.59283 (14)0.20757 (15)0.0734 (4)
H170.46800.65270.19080.088*
C180.4119 (3)0.48965 (12)0.16320 (12)0.0604 (4)
H180.54530.48040.11720.072*
N10.30501 (19)0.17179 (9)0.24060 (10)0.0527 (3)
H10.397 (3)0.1732 (13)0.3027 (14)0.066 (4)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C20.0521 (7)0.0509 (7)0.0556 (7)0.0122 (5)0.0034 (6)0.0143 (6)
C30.0785 (9)0.0594 (8)0.0559 (8)0.0142 (7)0.0073 (7)0.0128 (6)
C40.1052 (12)0.0700 (9)0.0583 (8)0.0204 (8)0.0091 (8)0.0225 (7)
C50.0859 (10)0.0597 (8)0.0655 (9)0.0183 (7)0.0016 (7)0.0255 (7)
C60.0543 (7)0.0504 (7)0.0614 (8)0.0093 (5)0.0064 (6)0.0183 (6)
C70.0547 (7)0.0476 (7)0.0595 (7)0.0083 (5)0.0012 (6)0.0217 (6)
C80.0604 (8)0.0652 (9)0.0672 (9)0.0004 (7)0.0016 (7)0.0231 (7)
C90.0791 (10)0.0627 (9)0.0734 (10)0.0087 (7)0.0137 (8)0.0192 (8)
C100.0935 (11)0.0570 (8)0.0580 (8)0.0140 (8)0.0090 (8)0.0130 (7)
C110.0819 (11)0.0673 (9)0.0728 (10)0.0147 (8)0.0162 (8)0.0145 (8)
C120.0646 (9)0.0564 (8)0.0788 (10)0.0017 (6)0.0114 (7)0.0134 (7)
C130.0523 (7)0.0469 (7)0.0489 (7)0.0089 (5)0.0042 (5)0.0093 (5)
C140.0610 (8)0.0571 (8)0.0674 (8)0.0119 (6)0.0053 (7)0.0160 (7)
C150.0747 (10)0.0723 (10)0.0744 (10)0.0002 (8)0.0043 (8)0.0277 (8)
C160.0932 (12)0.0606 (9)0.0760 (10)0.0017 (8)0.0151 (9)0.0300 (8)
C170.0845 (11)0.0602 (9)0.0810 (10)0.0244 (8)0.0089 (9)0.0215 (8)
C180.0621 (8)0.0595 (8)0.0618 (8)0.0179 (6)0.0014 (6)0.0162 (6)
N10.0583 (6)0.0468 (6)0.0540 (6)0.0091 (5)0.0049 (5)0.0154 (5)
Geometric parameters (Å, º) top
C2—N11.4685 (16)C9—C101.370 (2)
C2—C131.5064 (17)C9—H90.9300
C2—C31.5217 (19)C10—C111.372 (2)
C2—H20.9800C10—H100.9300
C3—C41.5211 (19)C11—C121.376 (2)
C3—H3A0.9700C11—H110.9300
C3—H3B0.9700C12—H120.9300
C4—C51.521 (2)C13—C141.3857 (18)
C4—H4A0.9700C13—C181.3881 (17)
C4—H4B0.9700C14—C151.375 (2)
C5—C61.522 (2)C14—H140.9300
C5—H5A0.9700C15—C161.380 (2)
C5—H5B0.9700C15—H150.9300
C6—N11.4648 (16)C16—C171.367 (2)
C6—C71.5072 (18)C16—H160.9300
C6—H60.9800C17—C181.382 (2)
C7—C81.3789 (19)C17—H170.9300
C7—C121.3867 (19)C18—H180.9300
C8—C91.381 (2)N1—H10.891 (16)
C8—H80.9300
N1—C2—C13109.73 (10)C9—C8—H8119.5
N1—C2—C3108.14 (10)C10—C9—C8120.55 (14)
C13—C2—C3113.09 (11)C10—C9—H9119.7
N1—C2—H2108.6C8—C9—H9119.7
C13—C2—H2108.6C9—C10—C11119.28 (14)
C3—C2—H2108.6C9—C10—H10120.4
C4—C3—C2111.00 (12)C11—C10—H10120.4
C4—C3—H3A109.4C10—C11—C12120.17 (15)
C2—C3—H3A109.4C10—C11—H11119.9
C4—C3—H3B109.4C12—C11—H11119.9
C2—C3—H3B109.4C11—C12—C7121.37 (14)
H3A—C3—H3B108.0C11—C12—H12119.3
C3—C4—C5110.73 (12)C7—C12—H12119.3
C3—C4—H4A109.5C14—C13—C18118.18 (12)
C5—C4—H4A109.5C14—C13—C2120.72 (11)
C3—C4—H4B109.5C18—C13—C2121.09 (12)
C5—C4—H4B109.5C15—C14—C13121.03 (13)
H4A—C4—H4B108.1C15—C14—H14119.5
C4—C5—C6111.35 (11)C13—C14—H14119.5
C4—C5—H5A109.4C14—C15—C16120.15 (15)
C6—C5—H5A109.4C14—C15—H15119.9
C4—C5—H5B109.4C16—C15—H15119.9
C6—C5—H5B109.4C17—C16—C15119.52 (14)
H5A—C5—H5B108.0C17—C16—H16120.2
N1—C6—C7110.02 (10)C15—C16—H16120.2
N1—C6—C5108.40 (11)C16—C17—C18120.58 (14)
C7—C6—C5112.75 (10)C16—C17—H17119.7
N1—C6—H6108.5C18—C17—H17119.7
C7—C6—H6108.5C17—C18—C13120.54 (14)
C5—C6—H6108.5C17—C18—H18119.7
C8—C7—C12117.66 (13)C13—C18—H18119.7
C8—C7—C6121.30 (12)C6—N1—C2113.14 (10)
C12—C7—C6121.04 (11)C6—N1—H1110.1 (9)
C7—C8—C9120.97 (14)C2—N1—H1109.7 (9)
C7—C8—H8119.5
N1—C2—C3—C456.90 (15)C6—C7—C12—C11179.08 (13)
C13—C2—C3—C4178.62 (11)N1—C2—C13—C1450.66 (15)
C2—C3—C4—C553.73 (18)C3—C2—C13—C1470.16 (15)
C3—C4—C5—C653.20 (18)N1—C2—C13—C18128.55 (12)
C4—C5—C6—N155.84 (15)C3—C2—C13—C18110.63 (14)
C4—C5—C6—C7177.89 (12)C18—C13—C14—C150.6 (2)
N1—C6—C7—C8130.46 (12)C2—C13—C14—C15178.63 (13)
C5—C6—C7—C8108.40 (14)C13—C14—C15—C160.3 (2)
N1—C6—C7—C1250.58 (15)C14—C15—C16—C170.3 (2)
C5—C6—C7—C1270.56 (16)C15—C16—C17—C180.6 (2)
C12—C7—C8—C90.1 (2)C16—C17—C18—C130.4 (2)
C6—C7—C8—C9179.06 (12)C14—C13—C18—C170.25 (19)
C7—C8—C9—C100.1 (2)C2—C13—C18—C17178.98 (12)
C8—C9—C10—C110.2 (2)C7—C6—N1—C2174.32 (10)
C9—C10—C11—C120.2 (2)C5—C6—N1—C261.97 (13)
C10—C11—C12—C70.2 (2)C13—C2—N1—C6173.66 (10)
C8—C7—C12—C110.1 (2)C3—C2—N1—C662.57 (14)
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C13–C18 and C7–C12 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cg1i0.973.003.719 (2)132
C10—H10···Cg1ii0.933.013.760 (2)139
C16—H16···Cg2iii0.933.033.799 (2)141
Symmetry codes: (i) x+2, y+1, z+2; (ii) x+1, y+2, z+1; (iii) x, y1, z.
Hydrogen-bond geometry (Å, º) top
Cg1 and Cg2 are the centroids of the C13–C18 and C7–C12 rings, respectively.
D—H···AD—HH···AD···AD—H···A
C3—H3A···Cg1i0.973.003.719 (2)131.97
C10—H10···Cg1ii0.933.013.760 (2)138.49
C16—H16···Cg2iii0.933.033.799 (2)141.22
Symmetry codes: (i) x+2, y+1, z+2; (ii) x+1, y+2, z+1; (iii) x, y1, z.
 

Acknowledgements

SP thanks the UGC, New Delhi, for financial assistance in the form of a Major Research Project.

References

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