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

Ravichandran, K.; Sakthivel, P.; Ramesh, P.; Ponnuswamy, S.; Ponnuswamy, M.N.

doi:10.1107/S1600536812007015

organic compounds

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ISSN: 2056-9890

Volume 68| Part 3| March 2012| Page o870

doi:10.1107/S1600536812007015

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

K. Ravichandran,^a P. Sakthivel,^b P. Ramesh,^a 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 9 January 2012; accepted 16 February 2012; online 29 February 2012)

In the title compound, C₂₀H₂₁NO₂, the piperidine ring adopts a distorted boat conformation. The phenyl rings substituted at the 2- and 6-positions of the piperidine ring subtend angles of 86.0 (1) and 67.3 (1)° with the mean plane of the piperidine ring (all six non-H atoms). The crystal packing features C—H⋯O interactions.

Related literature

For the biological activity of piperidine derivatives, see: Aridoss et al. (2009 ); Nalanishi et al. (1974 ); Michael (2001 ); Pinder (1992 ); Rubiralta et al. (1991 ). For puckering parameters, see: Cremer & Pople (1975 ). For asymmetry parameters, see: Nardelli (1983 ). For hydrogen-bond motifs, see: Bernstein et al.(1995 ).

Experimental

Crystal data

C₂₀H₂₁NO₂
M_r = 307.38
Monoclinic, P 2₁ /n
a = 10.6604 (6) Å
b = 15.7278 (7) Å
c = 10.8066 (5) Å
β = 110.120 (2)°
V = 1701.31 (15) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.20 × 0.20 × 0.20 mm

Data collection

Bruker SMART APEX CCD detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1998 ) T_min = 0.985, T_max = 0.985
16240 measured reflections
4162 independent reflections
2769 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.042
wR(F²) = 0.125
S = 1.04
4162 reflections
209 parameters
H-atom parameters constrained
Δρ_max = 0.19 e Å⁻³
Δρ_min = −0.13 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C6—H6⋯O1ⁱ	0.98	2.59	3.2951 (17)	129
Symmetry code: (i) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: SMART (Bruker, 1998); cell refinement: SAINT-Plus (Bruker, 1998); data reduction: SAINT-Plus; 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 and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812007015/bt5783sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812007015/bt5783Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536812007015/bt5783Isup3.cml

checkCIF report

Comment top

Piperidine derivatives are the valued heterocyclic compounds in the field of medicinal chemistry. The compounds possessing an amide bond linkage have a wide range of biological activities such as antimicrobial, anti-inflammatory, antiviral, antimalarial and general anesthetics (Aridoss et al., 2009). Functionalized piperidines are familiar substructures found in biologically active natural products and synthetic pharmaceuticals (Michael, 2001; Pinder, 1992; Rubiralta et al., 1991). 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 formyl substituted piperidine derivative crystallizes in monoclinic space groups P2₁/n. The piperidine ring adopts distorted boat conformation with the puckering parameters (Cremer & Pople, 1975) and the asymmetry parameters (Nardelli, 1983) are: q₂=0.648 (2) Å, q₃ = -0.047 (1) Å, ϕ₂ = -98.9 (1)° and Δ_s(N1 & C4)= 16.8 (1)°. The sum of the bond angles around N1 [359.2°] is in accordance with sp² hybridization.

The carbonyl group is oriented syn to C2 [C2—N1—C7—O1=] -6.5 (2)° and anti to C6 [C6—N1—C7—O1=] -176.7 (1)°. The best plane of the piperidine ring and the attached phenyl rings [C8—C13 & C16—C21] are twisted away by 86.0 (1)° & 67.3 (1)°. The two phenyl rings are approximately perpendicular to each other with a dihedral angle of 86.5 (1)°.

The crystal packing reveals that the symmetry related molecules are linked through a network of C—H···O type of intermolecular interactions. The atom C6 at (x, y, z) donates a proton to O1 at (-1/2 + x, 1/2 - y, -1/2 + z) forming a C(5) one dimensional chain running along the ac diagonal axis (Bernstein et al., 1995).

Related literature top

For the biological activity of piperidine derivatives, see: Aridoss et al. (2009); Nalanishi et al. (1974); Michael (2001); Pinder (1992); Rubiralta et al. (1991). For puckering parameters, see: Cremer & Pople (1975). For asymmetry parameters, see: Nardelli (1983). For hydrogen-bond motifs, see: Bernstein et al.(1995).

Experimental top

To ice-cold acetic anhydride (10 ml), 85% formic acid (5 ml) was added slowly and the resulting acetic acid–formic anhydride was cooled to 5° C and added slowly to a cold solution of piperidine-4-one (5 mmol) in anhydrous benzene (30 ml). The reaction mixture was stirred at room temperature for 5 h and the solution was poured into water (250 ml). The benzene layer was separated out, concentrated and recrystallized from benzene: pet-ether (60–80° C) in the ratio 1:1.

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); 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) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, showing the atomic numbering and displacement ellipsoids drawn at 50% probability level.
	Fig. 2. The crystal packing of the molecules. H atoms not involved in hydrogen bonding (dashed lines) have been omitted for clarity.

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

Crystal data top

C₂₀H₂₁NO₂	F(000) = 656
M_r = 307.38	D_x = 1.200 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2769 reflections
a = 10.6604 (6) Å	θ = 2.3–28.3°
b = 15.7278 (7) Å	µ = 0.08 mm⁻¹
c = 10.8066 (5) Å	T = 293 K
β = 110.120 (2)°	Block, yellow
V = 1701.31 (15) Å³	0.20 × 0.20 × 0.20 mm
Z = 4

Data collection top

Bruker SMART APEX CCD detector diffractometer	4162 independent reflections
Radiation source: fine-focus sealed tube	2769 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
ω scans	θ_max = 28.3°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −13→9
T_min = 0.985, T_max = 0.985	k = −17→20
16240 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.042	H-atom parameters constrained
wR(F²) = 0.125	w = 1/[σ²(F_o²) + (0.0489P)² + 0.2736P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max < 0.001
4162 reflections	Δρ_max = 0.19 e Å⁻³
209 parameters	Δρ_min = −0.13 e Å⁻³
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0063 (15)

Crystal data top

C₂₀H₂₁NO₂	V = 1701.31 (15) Å³
M_r = 307.38	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 10.6604 (6) Å	µ = 0.08 mm⁻¹
b = 15.7278 (7) Å	T = 293 K
c = 10.8066 (5) Å	0.20 × 0.20 × 0.20 mm
β = 110.120 (2)°

Data collection top

Bruker SMART APEX CCD detector diffractometer	4162 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1998)	2769 reflections with I > 2σ(I)
T_min = 0.985, T_max = 0.985	R_int = 0.021
16240 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.042	0 restraints
wR(F²) = 0.125	H-atom parameters constrained
S = 1.04	Δρ_max = 0.19 e Å⁻³
4162 reflections	Δρ_min = −0.13 e Å⁻³
209 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
O1	0.33930 (11)	0.19983 (7)	0.96574 (9)	0.0689 (3)
O2	0.12616 (13)	0.21093 (8)	0.35746 (10)	0.0845 (4)
N1	0.20536 (10)	0.17426 (7)	0.75311 (10)	0.0487 (3)
C2	0.31776 (13)	0.17185 (9)	0.70280 (12)	0.0483 (3)
H2	0.3914	0.2017	0.7688	0.058*
C3	0.28375 (14)	0.22558 (9)	0.57618 (13)	0.0554 (4)
C4	0.15392 (15)	0.19561 (10)	0.47344 (13)	0.0597 (4)
C5	0.05906 (14)	0.14749 (10)	0.52365 (12)	0.0598 (4)
H5A	0.0781	0.0872	0.5226	0.072*
H5B	−0.0312	0.1567	0.4633	0.072*
C6	0.06466 (13)	0.17169 (9)	0.66235 (13)	0.0530 (3)
H6	0.0275	0.2290	0.6582	0.064*
C7	0.22970 (15)	0.19192 (9)	0.88088 (13)	0.0563 (4)
H7	0.1558	0.1988	0.9071	0.068*
C8	0.36733 (12)	0.08118 (9)	0.69907 (12)	0.0477 (3)
C9	0.45199 (14)	0.04765 (10)	0.81673 (13)	0.0583 (4)
H9	0.4758	0.0808	0.8926	0.070*
C10	0.50188 (17)	−0.03415 (12)	0.82365 (16)	0.0715 (5)
H10	0.5580	−0.0555	0.9038	0.086*
C11	0.46891 (17)	−0.08374 (11)	0.71304 (19)	0.0732 (5)
H11	0.5018	−0.1389	0.7177	0.088*
C12	0.38724 (18)	−0.05151 (12)	0.59586 (18)	0.0781 (5)
H12	0.3655	−0.0847	0.5201	0.094*
C13	0.33629 (16)	0.03008 (11)	0.58839 (15)	0.0683 (4)
H13	0.2803	0.0508	0.5077	0.082*
C14	0.40046 (17)	0.22591 (12)	0.52432 (16)	0.0751 (5)
H14A	0.4797	0.2455	0.5923	0.113*
H14B	0.3801	0.2631	0.4495	0.113*
H14C	0.4148	0.1693	0.4986	0.113*
C15	0.25767 (18)	0.31820 (10)	0.60864 (17)	0.0709 (4)
H15A	0.1843	0.3194	0.6409	0.106*
H15B	0.2363	0.3523	0.5304	0.106*
H15C	0.3362	0.3404	0.6747	0.106*
C16	−0.01874 (13)	0.11249 (10)	0.71207 (13)	0.0553 (4)
C17	−0.14145 (15)	0.13908 (12)	0.71422 (15)	0.0681 (4)
H17	−0.1720	0.1935	0.6854	0.082*
C18	−0.21912 (18)	0.08524 (16)	0.75901 (18)	0.0855 (6)
H18	−0.3018	0.1035	0.7599	0.103*
C19	−0.1747 (2)	0.00528 (16)	0.8021 (2)	0.0905 (6)
H19	−0.2269	−0.0307	0.8326	0.109*
C20	−0.0538 (2)	−0.02166 (14)	0.8001 (2)	0.0942 (6)
H20	−0.0238	−0.0761	0.8291	0.113*
C21	0.02406 (18)	0.03149 (12)	0.75529 (19)	0.0774 (5)
H21	0.1063	0.0126	0.7542	0.093*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0658 (7)	0.0879 (8)	0.0450 (5)	−0.0068 (6)	0.0089 (5)	−0.0128 (5)
O2	0.0962 (9)	0.1036 (10)	0.0445 (6)	0.0147 (7)	0.0125 (5)	0.0114 (5)
N1	0.0453 (6)	0.0573 (7)	0.0408 (5)	0.0030 (5)	0.0113 (4)	−0.0060 (5)
C2	0.0450 (7)	0.0562 (8)	0.0407 (6)	0.0011 (6)	0.0112 (5)	−0.0026 (5)
C3	0.0598 (8)	0.0586 (9)	0.0485 (7)	0.0094 (7)	0.0194 (6)	0.0058 (6)
C4	0.0674 (9)	0.0618 (9)	0.0452 (7)	0.0186 (7)	0.0135 (6)	0.0028 (6)
C5	0.0524 (8)	0.0704 (10)	0.0453 (7)	0.0085 (7)	0.0024 (6)	−0.0057 (6)
C6	0.0457 (7)	0.0581 (9)	0.0497 (7)	0.0070 (6)	0.0095 (5)	−0.0057 (6)
C7	0.0590 (8)	0.0627 (9)	0.0473 (7)	−0.0003 (7)	0.0182 (6)	−0.0084 (6)
C8	0.0401 (6)	0.0572 (8)	0.0456 (6)	0.0030 (6)	0.0144 (5)	0.0026 (5)
C9	0.0570 (8)	0.0741 (10)	0.0458 (7)	0.0094 (7)	0.0201 (6)	0.0095 (6)
C10	0.0744 (10)	0.0827 (12)	0.0666 (9)	0.0262 (9)	0.0358 (8)	0.0315 (8)
C11	0.0781 (11)	0.0592 (10)	0.0960 (12)	0.0132 (8)	0.0477 (10)	0.0143 (9)
C12	0.0754 (11)	0.0703 (12)	0.0831 (11)	0.0124 (9)	0.0204 (9)	−0.0172 (9)
C13	0.0650 (9)	0.0731 (11)	0.0552 (8)	0.0185 (8)	0.0057 (7)	−0.0085 (7)
C14	0.0763 (11)	0.0899 (13)	0.0677 (9)	0.0150 (9)	0.0357 (8)	0.0199 (8)
C15	0.0842 (11)	0.0568 (10)	0.0740 (10)	0.0053 (8)	0.0302 (9)	0.0061 (7)
C16	0.0469 (7)	0.0628 (9)	0.0522 (7)	−0.0006 (7)	0.0117 (6)	−0.0136 (6)
C17	0.0517 (8)	0.0876 (12)	0.0619 (9)	0.0046 (8)	0.0157 (7)	−0.0091 (8)
C18	0.0546 (10)	0.1252 (18)	0.0783 (11)	−0.0028 (11)	0.0249 (8)	−0.0087 (11)
C19	0.0761 (13)	0.1046 (17)	0.0937 (13)	−0.0247 (12)	0.0330 (10)	−0.0060 (12)
C20	0.0880 (14)	0.0718 (13)	0.1283 (17)	−0.0076 (10)	0.0441 (13)	0.0039 (11)
C21	0.0652 (10)	0.0650 (11)	0.1073 (13)	0.0013 (8)	0.0365 (10)	−0.0046 (9)

Geometric parameters (Å, º) top

O1—C7	1.2183 (17)	C10—H10	0.9300
O2—C4	1.2088 (16)	C11—C12	1.364 (2)
N1—C7	1.3433 (16)	C11—H11	0.9300
N1—C2	1.4768 (16)	C12—C13	1.385 (2)
N1—C6	1.4837 (16)	C12—H12	0.9300
C2—C8	1.5261 (19)	C13—H13	0.9300
C2—C3	1.5416 (18)	C14—H14A	0.9600
C2—H2	0.9800	C14—H14B	0.9600
C3—C4	1.521 (2)	C14—H14C	0.9600
C3—C14	1.530 (2)	C15—H15A	0.9600
C3—C15	1.546 (2)	C15—H15B	0.9600
C4—C5	1.506 (2)	C15—H15C	0.9600
C5—C6	1.5276 (18)	C16—C21	1.379 (2)
C5—H5A	0.9700	C16—C17	1.381 (2)
C5—H5B	0.9700	C17—C18	1.383 (3)
C6—C16	1.508 (2)	C17—H17	0.9300
C6—H6	0.9800	C18—C19	1.368 (3)
C7—H7	0.9300	C18—H18	0.9300
C8—C13	1.3834 (19)	C19—C20	1.364 (3)
C8—C9	1.3856 (18)	C19—H19	0.9300
C9—C10	1.384 (2)	C20—C21	1.378 (3)
C9—H9	0.9300	C20—H20	0.9300
C10—C11	1.368 (2)	C21—H21	0.9300

C7—N1—C2	119.30 (11)	C9—C10—H10	119.9
C7—N1—C6	118.63 (11)	C12—C11—C10	119.29 (16)
C2—N1—C6	121.31 (10)	C12—C11—H11	120.4
N1—C2—C8	111.46 (11)	C10—C11—H11	120.4
N1—C2—C3	109.86 (10)	C11—C12—C13	120.72 (16)
C8—C2—C3	117.81 (11)	C11—C12—H12	119.6
N1—C2—H2	105.6	C13—C12—H12	119.6
C8—C2—H2	105.6	C8—C13—C12	121.03 (14)
C3—C2—H2	105.6	C8—C13—H13	119.5
C4—C3—C14	112.59 (12)	C12—C13—H13	119.5
C4—C3—C2	110.81 (12)	C3—C14—H14A	109.5
C14—C3—C2	110.75 (11)	C3—C14—H14B	109.5
C4—C3—C15	105.55 (12)	H14A—C14—H14B	109.5
C14—C3—C15	108.19 (13)	C3—C14—H14C	109.5
C2—C3—C15	108.72 (11)	H14A—C14—H14C	109.5
O2—C4—C5	121.24 (14)	H14B—C14—H14C	109.5
O2—C4—C3	122.13 (15)	C3—C15—H15A	109.5
C5—C4—C3	116.61 (11)	C3—C15—H15B	109.5
C4—C5—C6	115.08 (12)	H15A—C15—H15B	109.5
C4—C5—H5A	108.5	C3—C15—H15C	109.5
C6—C5—H5A	108.5	H15A—C15—H15C	109.5
C4—C5—H5B	108.5	H15B—C15—H15C	109.5
C6—C5—H5B	108.5	C21—C16—C17	118.60 (16)
H5A—C5—H5B	107.5	C21—C16—C6	121.60 (13)
N1—C6—C16	111.54 (11)	C17—C16—C6	119.79 (14)
N1—C6—C5	110.17 (11)	C16—C17—C18	120.33 (18)
C16—C6—C5	111.52 (12)	C16—C17—H17	119.8
N1—C6—H6	107.8	C18—C17—H17	119.8
C16—C6—H6	107.8	C19—C18—C17	120.22 (18)
C5—C6—H6	107.8	C19—C18—H18	119.9
O1—C7—N1	126.23 (14)	C17—C18—H18	119.9
O1—C7—H7	116.9	C20—C19—C18	119.9 (2)
N1—C7—H7	116.9	C20—C19—H19	120.0
C13—C8—C9	117.32 (13)	C18—C19—H19	120.0
C13—C8—C2	125.71 (12)	C19—C20—C21	120.2 (2)
C9—C8—C2	116.97 (12)	C19—C20—H20	119.9
C10—C9—C8	121.34 (14)	C21—C20—H20	119.9
C10—C9—H9	119.3	C20—C21—C16	120.67 (17)
C8—C9—H9	119.3	C20—C21—H21	119.7
C11—C10—C9	120.28 (14)	C16—C21—H21	119.7
C11—C10—H10	119.9

C7—N1—C2—C8	96.72 (14)	C6—N1—C7—O1	−176.66 (14)
C6—N1—C2—C8	−93.42 (13)	N1—C2—C8—C13	100.41 (16)
C7—N1—C2—C3	−130.81 (13)	C3—C2—C8—C13	−27.9 (2)
C6—N1—C2—C3	39.05 (16)	N1—C2—C8—C9	−80.34 (14)
N1—C2—C3—C4	−55.83 (14)	C3—C2—C8—C9	151.32 (13)
C8—C2—C3—C4	73.26 (15)	C13—C8—C9—C10	−1.0 (2)
N1—C2—C3—C14	178.49 (12)	C2—C8—C9—C10	179.73 (13)
C8—C2—C3—C14	−52.43 (17)	C8—C9—C10—C11	0.5 (2)
N1—C2—C3—C15	59.74 (15)	C9—C10—C11—C12	0.5 (3)
C8—C2—C3—C15	−171.17 (12)	C10—C11—C12—C13	−0.9 (3)
C14—C3—C4—O2	−34.5 (2)	C9—C8—C13—C12	0.5 (2)
C2—C3—C4—O2	−159.11 (14)	C2—C8—C13—C12	179.78 (15)
C15—C3—C4—O2	83.37 (17)	C11—C12—C13—C8	0.4 (3)
C14—C3—C4—C5	147.10 (14)	N1—C6—C16—C21	−47.78 (18)
C2—C3—C4—C5	22.44 (17)	C5—C6—C16—C21	75.87 (17)
C15—C3—C4—C5	−95.08 (15)	N1—C6—C16—C17	132.58 (13)
O2—C4—C5—C6	−148.57 (14)	C5—C6—C16—C17	−103.77 (15)
C3—C4—C5—C6	29.89 (18)	C21—C16—C17—C18	0.0 (2)
C7—N1—C6—C16	−53.53 (16)	C6—C16—C17—C18	179.70 (14)
C2—N1—C6—C16	136.54 (12)	C16—C17—C18—C19	0.3 (3)
C7—N1—C6—C5	−177.94 (13)	C17—C18—C19—C20	−0.4 (3)
C2—N1—C6—C5	12.13 (18)	C18—C19—C20—C21	0.2 (3)
C4—C5—C6—N1	−47.61 (17)	C19—C20—C21—C16	0.1 (3)
C4—C5—C6—C16	−172.03 (12)	C17—C16—C21—C20	−0.2 (3)
C2—N1—C7—O1	−6.5 (2)	C6—C16—C21—C20	−179.87 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O1ⁱ	0.98	2.59	3.2951 (17)	129

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Experimental details

Crystal data
Chemical formula	C₂₀H₂₁NO₂
M_r	307.38
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	10.6604 (6), 15.7278 (7), 10.8066 (5)
β (°)	110.120 (2)
V (Å³)	1701.31 (15)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.20 × 0.20 × 0.20

Data collection
Diffractometer	Bruker SMART APEX CCD detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1998)
T_min, T_max	0.985, 0.985
No. of measured, independent and observed [I > 2σ(I)] reflections	16240, 4162, 2769
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.666

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.042, 0.125, 1.04
No. of reflections	4162
No. of parameters	209
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.19, −0.13

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C6—H6···O1ⁱ	0.98	2.59	3.2951 (17)	128.5

Symmetry code: (i) x−1/2, −y+1/2, z−1/2.

Acknowledgements

KR thanks the TBI Consultancy, University of Madras, India, for the data collection and the management of Kandaswami Kandar's College, Velur, Namakkal, Tamilnadu, India, for encouragement.

References

Aridoss, G., Parthiban, P., Ramachandran, R., Prakash, M., Kabilan, S. & Jeong, Y. T. (2009). Eur. J. Med. Chem. 44, 577–592. Web of Science CrossRef PubMed CAS Google Scholar
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N. L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker. (1998). SMART, SAINT-Plus and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358. CrossRef CAS Web of Science Google Scholar
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565. CrossRef IUCr Journals Google Scholar
Michael, J. P. (2001). The Alkaloids. Chemistry and Biology, edited by G. A. Cordell, Vol. 55, pp. 91–258. New York: Academic Press. Google Scholar
Nalanishi, M., Shiraki, M., Kobayakawa, T. & Kobayashi, R. (1974). Japanese Patent No. 74-3987. Google Scholar
Nardelli, M. (1983). Acta Cryst. C39, 1141–1142. CrossRef CAS Web of Science IUCr Journals Google Scholar
Pinder, A. R. (1992). Nat. Prod. Rep. 9, 491–504. CrossRef CAS Web of Science Google Scholar
Rubiralta, M., Giralt, E. & Diez, A. (1991). Piperidine: Structure, Preparation, Reactivity, and Synthetic Applications of Piperidine and its Derivatives, pp. 225–312. Amsterdam: Elsevier. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar