3-Ethyl-cis-2,6-di­phenyl­piperidine

Maheshwaran, V.; Abdul Basheer, S.; Akila, A.; Ponnuswamy, S.; Ponnuswamy, M.N.

doi:10.1107/S1600536813021417

organic compounds

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ISSN: 2056-9890

Volume 69| Part 9| September 2013| Page o1441

doi:10.1107/S1600536813021417

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3-Ethyl-cis-2,6-diphenylpiperidine

V. Maheshwaran,^a S. Abdul Basheer,^b A. Akila,^b S. Ponnuswamy ^b and M. N. Ponnuswamy ^a ^*

^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 11 July 2013; accepted 1 August 2013; online 17 August 2013)

In the title compound, C₁₉H₂₃N, the piperidine ring adopts a chair conformation. The phenyl rings at the 2,6-positions of the piperidine ring occupy equatorial orientations. The crystal structure features C—H⋯π interactions.

Related literature

For the biological activity of piperidine derivatives, see: Nalanishi et al. (1974 ). For the synthesis, see: Ponnuswamy et al. (2002 ). For puckering parameters, see: Cremer & Pople (1975 ) and for asymmetry parameters, see: Nardelli (1983 ).

Experimental

Crystal data

C₁₉H₂₃N
M_r = 265.38
Triclinic, $[P \overline 1]$
a = 5.5384 (5) Å
b = 9.2717 (9) Å
c = 16.0483 (14) Å
α = 75.508 (5)°
β = 89.474 (5)°
γ = 81.625 (5)°
V = 789.04 (13) Å³
Z = 2
Mo Kα radiation
μ = 0.06 mm⁻¹
T = 293 K
0.20 × 0.19 × 0.19 mm

Data collection

Bruker SMART APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2008 ) T_min = 0.987, T_max = 0.988
11467 measured reflections
3251 independent reflections
2579 reflections with I > 2σ(I)
R_int = 0.025

Refinement

R[F² > 2σ(F²)] = 0.043
wR(F²) = 0.124
S = 1.03
3251 reflections
185 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg2 and Cg3 are the centroids of the C7–C12 and C13–C18 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C5—H5B⋯Cg2ⁱ	0.97	3.14	3.893 (2)	136
C10—H10⋯Cg3ⁱⁱ	0.93	2.92	3.702 (2)	142
C20—H20A⋯Cg3ⁱⁱⁱ	0.96	3.17	3.926 (2)	137
Symmetry codes: (i) -x+1, -y, -z+1; (ii) -x, -y+1, -z+1; (iii) -x+1, -y+1, -z.

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT; 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 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813021417/ng5337sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813021417/ng5337Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813021417/ng5337Isup3.cml

checkCIF report

Comment top

Piperidine derivatives are the valued heterocyclic compounds in the field of medicinal chemistry. As an example, piperidines have been found to exhibit blood cholesterol-lowering activities (Nalanishi et al., 1974). Against this background and to ascertain the molecular structure and conformation, the X-ray crystal structure determination of the title compound has been carried out.

The ORTEP plot of the molecule is shown in Fig. 1. The piperidine ring adopts chair conformation with the puckering parameters (Cremer & Pople, 1975) and the asymmetry parameters (Nardelli,1983) are: q₂=0.039 (14) Å, q₃ = 0.576 (14) Å, ϕ₂ = 1(2)° and Δ_s (N1& C4)= 0.86 (12)°.

The planar phenyl rings at 2,6- positions of the piperidine ring occupy equatorial orientation as can be seen from the corresponding torsion angles [C4—C3—C2—C13=] 175.8 (1)° & [C4—C5—C6—C7=] -177.5 (1)°, respectively. The dihedral angle between the two phenyl rings is 64.22 (7)°. The ethyl group substituted at 3^rd position of the piperdine moiety is in equatorial oreintation.

The molecules are controlled by C—H ··· π type of intermolecular interactions in addition to van der Waals forces. The molecules are stacked one over the other while packing in the unit cell (Fig. 2).

Related literature top

For the biological activity of piperidine derivatives, see: Nalanishi et al. (1974). For the synthesis, see: Ponnuswamy et al. (2002). For puckering parameters, see: Cremer & Pople (1975) and 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 h. Potassium hydroxide pellets (2.8 g) were added to the mixture and the contents were refluxed for another 2 h. The reaction mixture was cooled (Ponnuswamy et al., 2002). The product formed was filtered and recrystallized from ethanol.

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

	Fig. 1. The molecular structure of the title compound, showing the atomic numbering and displacement ellipsoids drawn at 30% probability level.
	Fig. 2. The crystal packing of the molecules viewed down a axis.

3-Ethyl-cis-2,6-diphenylpiperidine top

Crystal data top

C₁₉H₂₃N	Z = 2
M_r = 265.38	F(000) = 288
Triclinic, P1	D_x = 1.117 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 5.5384 (5) Å	Cell parameters from 2579 reflections
b = 9.2717 (9) Å	θ = 1.3–26.5°
c = 16.0483 (14) Å	µ = 0.06 mm⁻¹
α = 75.508 (5)°	T = 293 K
β = 89.474 (5)°	Block, colorless
γ = 81.625 (5)°	0.20 × 0.19 × 0.19 mm
V = 789.04 (13) Å³

Data collection top

Bruker SMART APEXII CCD diffractometer	3251 independent reflections
Radiation source: fine-focus sealed tube	2579 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.025
ω and ϕ scans	θ_max = 26.5°, θ_min = 1.3°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −6→6
T_min = 0.987, T_max = 0.988	k = −11→8
11467 measured reflections	l = −20→20

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.043	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.124	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ²(F_o²) + (0.0584P)² + 0.1238P] where P = (F_o² + 2F_c²)/3
3251 reflections	(Δ/σ)_max < 0.001
185 parameters	Δρ_max = 0.13 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₁₉H₂₃N	γ = 81.625 (5)°
M_r = 265.38	V = 789.04 (13) Å³
Triclinic, P1	Z = 2
a = 5.5384 (5) Å	Mo Kα radiation
b = 9.2717 (9) Å	µ = 0.06 mm⁻¹
c = 16.0483 (14) Å	T = 293 K
α = 75.508 (5)°	0.20 × 0.19 × 0.19 mm
β = 89.474 (5)°

Data collection top

Bruker SMART APEXII CCD diffractometer	3251 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2008)	2579 reflections with I > 2σ(I)
T_min = 0.987, T_max = 0.988	R_int = 0.025
11467 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.043	0 restraints
wR(F²) = 0.124	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.13 e Å⁻³
3251 reflections	Δρ_min = −0.18 e Å⁻³
185 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

	x	y	z	U_iso*/U_eq
C2	0.1613 (2)	0.41471 (13)	0.23423 (7)	0.0434 (3)
H2	0.0128	0.3751	0.2238	0.052*
C3	0.3820 (2)	0.31957 (13)	0.20539 (8)	0.0471 (3)
H3	0.5289	0.3604	0.2160	0.057*
C4	0.4049 (3)	0.15761 (15)	0.26061 (9)	0.0594 (4)
H4A	0.2685	0.1119	0.2470	0.071*
H4B	0.5538	0.1004	0.2466	0.071*
C5	0.4091 (3)	0.14914 (15)	0.35648 (9)	0.0582 (4)
H5A	0.5578	0.1813	0.3719	0.070*
H5B	0.4089	0.0456	0.3888	0.070*
C6	0.1893 (2)	0.24831 (14)	0.38030 (8)	0.0484 (3)
H6	0.0405	0.2116	0.3672	0.058*
C7	0.1925 (2)	0.24838 (13)	0.47436 (8)	0.0471 (3)
C8	0.0291 (3)	0.17969 (17)	0.53029 (9)	0.0612 (4)
H8	−0.0888	0.1347	0.5095	0.073*
C9	0.0372 (3)	0.17646 (19)	0.61675 (10)	0.0708 (4)
H9	−0.0737	0.1285	0.6535	0.085*
C10	0.2063 (3)	0.24306 (17)	0.64857 (9)	0.0639 (4)
H10	0.2111	0.2413	0.7067	0.077*
C11	0.3691 (3)	0.31261 (19)	0.59385 (10)	0.0721 (4)
H11	0.4852	0.3585	0.6150	0.086*
C12	0.3625 (3)	0.31531 (18)	0.50754 (9)	0.0663 (4)
H12	0.4745	0.3630	0.4712	0.080*
C13	0.1329 (2)	0.57950 (13)	0.18804 (7)	0.0429 (3)
C14	0.3020 (2)	0.66778 (14)	0.20280 (8)	0.0501 (3)
H14	0.4373	0.6233	0.2389	0.060*
C15	0.2726 (3)	0.82000 (15)	0.16494 (9)	0.0596 (4)
H15	0.3872	0.8774	0.1759	0.071*
C16	0.0745 (3)	0.88777 (16)	0.11094 (9)	0.0657 (4)
H16	0.0540	0.9909	0.0859	0.079*
C17	−0.0922 (3)	0.80212 (17)	0.09430 (9)	0.0665 (4)
H17	−0.2250	0.8472	0.0572	0.080*
C18	−0.0642 (2)	0.64924 (16)	0.13235 (8)	0.0545 (3)
H18	−0.1786	0.5924	0.1206	0.065*
C19	0.3650 (3)	0.32871 (17)	0.10912 (9)	0.0609 (4)
H19A	0.2269	0.2818	0.0983	0.073*
H19B	0.3334	0.4339	0.0778	0.073*
C20	0.5909 (3)	0.2544 (2)	0.07412 (11)	0.0823 (5)
H20A	0.5665	0.2649	0.0136	0.124*
H20B	0.6213	0.1494	0.1034	0.124*
H20C	0.7282	0.3016	0.0831	0.124*
N1	0.1873 (2)	0.40159 (11)	0.32687 (6)	0.0463 (3)
H1	0.069 (3)	0.4663 (17)	0.3429 (10)	0.064 (4)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C2	0.0430 (6)	0.0478 (6)	0.0404 (6)	−0.0064 (5)	0.0015 (5)	−0.0133 (5)
C3	0.0495 (7)	0.0477 (7)	0.0462 (6)	−0.0048 (5)	0.0039 (5)	−0.0172 (5)
C4	0.0736 (9)	0.0475 (7)	0.0576 (8)	0.0000 (6)	0.0069 (7)	−0.0194 (6)
C5	0.0725 (9)	0.0444 (7)	0.0532 (8)	0.0003 (6)	0.0024 (6)	−0.0092 (6)
C6	0.0534 (7)	0.0488 (7)	0.0438 (6)	−0.0120 (5)	0.0022 (5)	−0.0106 (5)
C7	0.0521 (7)	0.0439 (6)	0.0435 (6)	−0.0052 (5)	0.0022 (5)	−0.0085 (5)
C8	0.0607 (8)	0.0709 (9)	0.0558 (8)	−0.0190 (7)	0.0106 (6)	−0.0180 (7)
C9	0.0776 (10)	0.0810 (10)	0.0539 (8)	−0.0192 (8)	0.0214 (7)	−0.0138 (7)
C10	0.0784 (10)	0.0673 (9)	0.0432 (7)	0.0027 (7)	0.0035 (7)	−0.0163 (6)
C11	0.0844 (11)	0.0823 (11)	0.0559 (8)	−0.0238 (9)	−0.0037 (8)	−0.0226 (8)
C12	0.0765 (10)	0.0774 (10)	0.0502 (8)	−0.0329 (8)	0.0065 (7)	−0.0137 (7)
C13	0.0443 (6)	0.0483 (6)	0.0359 (6)	−0.0011 (5)	0.0050 (5)	−0.0136 (5)
C14	0.0546 (7)	0.0511 (7)	0.0450 (6)	−0.0042 (5)	−0.0004 (5)	−0.0148 (5)
C15	0.0754 (9)	0.0524 (8)	0.0544 (8)	−0.0132 (7)	0.0103 (7)	−0.0180 (6)
C16	0.0847 (11)	0.0482 (7)	0.0547 (8)	0.0038 (7)	0.0147 (7)	−0.0037 (6)
C17	0.0634 (9)	0.0698 (9)	0.0517 (8)	0.0098 (7)	−0.0022 (6)	0.0007 (7)
C18	0.0489 (7)	0.0632 (8)	0.0477 (7)	−0.0033 (6)	−0.0004 (5)	−0.0101 (6)
C19	0.0698 (9)	0.0651 (8)	0.0499 (7)	−0.0034 (7)	0.0078 (6)	−0.0223 (6)
C20	0.0885 (12)	0.0953 (13)	0.0677 (10)	−0.0023 (10)	0.0219 (9)	−0.0361 (9)
N1	0.0537 (6)	0.0443 (6)	0.0391 (5)	−0.0011 (5)	0.0045 (4)	−0.0109 (4)

Geometric parameters (Å, º) top

C2—N1	1.4678 (14)	C10—H10	0.9300
C2—C13	1.5080 (16)	C11—C12	1.380 (2)
C2—C3	1.5383 (17)	C11—H11	0.9300
C2—H2	0.9800	C12—H12	0.9300
C3—C4	1.5287 (18)	C13—C14	1.3882 (17)
C3—C19	1.5289 (17)	C13—C18	1.3898 (17)
C3—H3	0.9800	C14—C15	1.3760 (18)
C4—C5	1.5209 (18)	C14—H14	0.9300
C4—H4A	0.9700	C15—C16	1.376 (2)
C4—H4B	0.9700	C15—H15	0.9300
C5—C6	1.5217 (19)	C16—C17	1.371 (2)
C5—H5A	0.9700	C16—H16	0.9300
C5—H5B	0.9700	C17—C18	1.382 (2)
C6—N1	1.4631 (15)	C17—H17	0.9300
C6—C7	1.5099 (16)	C18—H18	0.9300
C6—H6	0.9800	C19—C20	1.512 (2)
C7—C8	1.3773 (19)	C19—H19A	0.9700
C7—C12	1.3786 (19)	C19—H19B	0.9700
C8—C9	1.381 (2)	C20—H20A	0.9600
C8—H8	0.9300	C20—H20B	0.9600
C9—C10	1.362 (2)	C20—H20C	0.9600
C9—H9	0.9300	N1—H1	0.902 (16)
C10—C11	1.368 (2)

N1—C2—C13	108.11 (9)	C11—C10—H10	120.4
N1—C2—C3	109.21 (10)	C10—C11—C12	120.54 (14)
C13—C2—C3	113.50 (10)	C10—C11—H11	119.7
N1—C2—H2	108.6	C12—C11—H11	119.7
C13—C2—H2	108.6	C7—C12—C11	121.02 (14)
C3—C2—H2	108.6	C7—C12—H12	119.5
C4—C3—C19	112.37 (10)	C11—C12—H12	119.5
C4—C3—C2	109.21 (10)	C14—C13—C18	117.86 (12)
C19—C3—C2	111.62 (10)	C14—C13—C2	120.10 (10)
C4—C3—H3	107.8	C18—C13—C2	122.01 (11)
C19—C3—H3	107.8	C15—C14—C13	121.05 (12)
C2—C3—H3	107.8	C15—C14—H14	119.5
C5—C4—C3	112.36 (10)	C13—C14—H14	119.5
C5—C4—H4A	109.1	C16—C15—C14	120.39 (14)
C3—C4—H4A	109.1	C16—C15—H15	119.8
C5—C4—H4B	109.1	C14—C15—H15	119.8
C3—C4—H4B	109.1	C17—C16—C15	119.47 (13)
H4A—C4—H4B	107.9	C17—C16—H16	120.3
C4—C5—C6	111.12 (11)	C15—C16—H16	120.3
C4—C5—H5A	109.4	C16—C17—C18	120.44 (13)
C6—C5—H5A	109.4	C16—C17—H17	119.8
C4—C5—H5B	109.4	C18—C17—H17	119.8
C6—C5—H5B	109.4	C17—C18—C13	120.78 (13)
H5A—C5—H5B	108.0	C17—C18—H18	119.6
N1—C6—C7	109.94 (10)	C13—C18—H18	119.6
N1—C6—C5	107.98 (10)	C20—C19—C3	114.38 (13)
C7—C6—C5	112.76 (10)	C20—C19—H19A	108.7
N1—C6—H6	108.7	C3—C19—H19A	108.7
C7—C6—H6	108.7	C20—C19—H19B	108.7
C5—C6—H6	108.7	C3—C19—H19B	108.7
C8—C7—C12	117.64 (12)	H19A—C19—H19B	107.6
C8—C7—C6	121.42 (11)	C19—C20—H20A	109.5
C12—C7—C6	120.93 (11)	C19—C20—H20B	109.5
C7—C8—C9	121.17 (14)	H20A—C20—H20B	109.5
C7—C8—H8	119.4	C19—C20—H20C	109.5
C9—C8—H8	119.4	H20A—C20—H20C	109.5
C10—C9—C8	120.50 (14)	H20B—C20—H20C	109.5
C10—C9—H9	119.8	C6—N1—C2	113.77 (9)
C8—C9—H9	119.8	C6—N1—H1	110.9 (10)
C9—C10—C11	119.13 (13)	C2—N1—H1	109.8 (10)
C9—C10—H10	120.4

N1—C2—C3—C4	55.09 (13)	C10—C11—C12—C7	0.0 (3)
C13—C2—C3—C4	175.78 (10)	N1—C2—C13—C14	52.66 (14)
N1—C2—C3—C19	179.96 (10)	C3—C2—C13—C14	−68.65 (14)
C13—C2—C3—C19	−59.35 (14)	N1—C2—C13—C18	−125.03 (12)
C19—C3—C4—C5	−177.17 (12)	C3—C2—C13—C18	113.65 (13)
C2—C3—C4—C5	−52.74 (15)	C18—C13—C14—C15	1.34 (18)
C3—C4—C5—C6	53.94 (16)	C2—C13—C14—C15	−176.45 (11)
C4—C5—C6—N1	−55.80 (14)	C13—C14—C15—C16	−0.4 (2)
C4—C5—C6—C7	−177.47 (11)	C14—C15—C16—C17	−0.7 (2)
N1—C6—C7—C8	129.57 (13)	C15—C16—C17—C18	1.0 (2)
C5—C6—C7—C8	−109.88 (14)	C16—C17—C18—C13	0.0 (2)
N1—C6—C7—C12	−51.55 (16)	C14—C13—C18—C17	−1.11 (19)
C5—C6—C7—C12	69.00 (16)	C2—C13—C18—C17	176.64 (11)
C12—C7—C8—C9	−0.7 (2)	C4—C3—C19—C20	−64.41 (17)
C6—C7—C8—C9	178.18 (13)	C2—C3—C19—C20	172.50 (13)
C7—C8—C9—C10	0.7 (2)	C7—C6—N1—C2	−174.65 (10)
C8—C9—C10—C11	−0.3 (2)	C5—C6—N1—C2	61.95 (13)
C9—C10—C11—C12	−0.1 (2)	C13—C2—N1—C6	173.60 (10)
C8—C7—C12—C11	0.4 (2)	C3—C2—N1—C6	−62.46 (13)
C6—C7—C12—C11	−178.57 (14)

Hydrogen-bond geometry (Å, º) top

Cg2 and Cg3 are the centroids of the C7–C12 and C13–C18 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5B···Cg2ⁱ	0.97	3.14	3.893 (2)	136
C10—H10···Cg3ⁱⁱ	0.93	2.92	3.702 (2)	142
C20—H20A···Cg3ⁱⁱⁱ	0.96	3.17	3.926 (2)	137

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

Hydrogen-bond geometry (Å, º) top

Cg2 and Cg3 are the centroids of the C7–C12 and C13–C18 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C5—H5B···Cg2ⁱ	0.97	3.14	3.893 (2)	135.49
C10—H10···Cg3ⁱⁱ	0.93	2.92	3.702 (2)	142.35
C20—H20A···Cg3ⁱⁱⁱ	0.96	3.17	3.926 (2)	137.18

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

Acknowledgements

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

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Volume 69| Part 9| September 2013| Page o1441

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