r-2,c-6-Bis(3-methoxy­phen­yl)-t-3,t-5-dimethyl­piperidin-4-one

Parthiban, P.; Ramkumar, V.; Kumar, N.A.; Kim, J.S.; Jeong, Y.T.

doi:10.1107/S1600536808023490

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 64| Part 8| August 2008| Page o1631

doi:10.1107/S1600536808023490

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r-2,c-6-Bis(3-methoxyphenyl)-t-3,t-5-dimethylpiperidin-4-one

P. Parthiban,^a V. Ramkumar,^b Nanjundan Ashok Kumar,^a Jong Su Kim ^a and Yeon Tae Jeong ^a ^*

^aDivision of Image Science and Information Engineering, Pukyong National University, Busan 608 739, Republic of Korea, and ^bDepartment of Chemistry, IIT Madras, Chennai, Tamilnadu, India
^*Correspondence e-mail: ytjeong@pknu.ac.kr

(Received 22 July 2008; accepted 25 July 2008; online 31 July 2008)

In the title compound, C₂₁H₂₅NO₃, the piperidinone ring adopts a chair conformation with an equatorial orientation of all substituents; the 3-methoxyphenyl groups make a dihedral angle of 60.26 (15)°. The carbonyl group O atom is disordered over two positions in a 0.643 (3):0.357 (3) ratio. The crystal structure is stabilized by N—H⋯O and C—H⋯O hydrogen bonding.

Related literature

For related literature, see: Angle et al. (1995 ); Balamurugan et al. (2008 ); Gayathri et al. (2008 ); Katritzky et al. (1990 ); Ramachandran et al. (2007 ); Thiruvalluvar et al. (2007 ; Cremer & Pople (1975 ); Noller & Baliah (1948 ).

Experimental

Crystal data

C₂₁H₂₅NO₃
M_r = 339.42
Monoclinic, C 2/c
a = 20.9885 (6) Å
b = 9.7699 (2) Å
c = 19.8153 (5) Å
β = 109.459 (2)°
V = 3831.14 (17) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 298 (2) K
0.25 × 0.23 × 0.22 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 1999 ) T_min = 0.931, T_max = 0.983
23076 measured reflections
4624 independent reflections
2715 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.163
S = 0.92
4624 reflections
239 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.12 e Å⁻³
Δρ_min = −0.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1A⋯O1ⁱ	0.881 (18)	2.414 (19)	3.2784 (18)	167.1 (15)
C2—H2⋯O3ⁱ	0.98	2.47	3.335 (2)	146
Symmetry code: (i) $[-x+1, y, -z+{\script{1\over 2}}]$ .

Data collection: APEX2 (Bruker–Nonius, 2004 ); cell refinement: APEX2; data reduction: SAINT-Plus (Bruker–Nonius, 2004); 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808023490/bx2164sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808023490/bx2164Isup2.hkl

checkCIF report

Comment top

Substituted piperidin-4-ones are very important class of compounds due to their presence in a wide variety of naturally occurring alkaloids, active pharmaceutical ingredients and intermediates and as building blocks of many drugs. (Angle & Breitenbucher, 1995; Katritzky & Fan, 1990). The piperidone heterocycle predominantly adopts the chair conformation (Ramachandran et al., 2007; Balamurugan et al., 2008) whereas depending upon the substitution, the configuration and conformation can be different (Thiruvalluvar et al., 2007; Gayathri et al., 2008). Hence, the present single-crystal XRD studies on the title compound have been carried out to find out the impact on the configuration and conformation of the piperidone ring due to the presence of methyl group on both sides of the carbonyl and methoxy group on the meta position of the phenyl rings.

In the title compound C₂₁H₂₅NO₃, as shown in figure, the piperidone heterocycle adopts a chair conformation with equatorial disposition of all the substituents. The equatorial orientations of the methyl and phenyl groups are confirmed by their torsion angles. The aryl groups attached to to the piperidone ring on both sides of the secondary amino group make a dihedral angle of 60.26 (15)°.

The analysis of torsion angles, asymmetry parameters and least-squares plane calculation shows that the piperidone ring adopts chair conformation with deviation of ring atoms N1 and C3 from the C1/C2/C4/C5 plane by -0.677 and 0.563 Å;, respectively. The ring puckering parameters for N1/C1/C2/C3/C4/C5 atoms are q2 = 0.0851 (17), q3 = 0.5515, Q_T = 0.5580 (16) Å and θ = 8.77 (17)° (Cremer & Pople, 1975).

Related literature top

For related literature, see: Angle et al. (1995); Balamurugan et al. (2008); Gayathri et al. (2008); Katritzky et al. (1990); Ramachandran et al. (2007); Thiruvalluvar et al. (2007; Cremer & Pople (1975); Noller & Baliah (1948).

Experimental top

The title compound was synthesized by the one pot condensation of 2-pentanone, meta methoxybenzaldehyde and ammonium acetate in 1:2:1 ratio, using ethanol as a solvent by adopting the literature procedure of modified Mannich reaction, reported by Noller & Baliah (1948) for similar type compounds. The mixture was warmed and kept aside overnight. The formed 2,6-bis(3-methoxyphenyl)-3, 5-dimethylpiperidin-4-one was filtered off and washed with 1:5 ethanol, ether mixture. Thus, the obtained crude product was purified by recrystallization with ethanol to afford the colorless crystals with diffraction quality.

Computing details top

Data collection: APEX2 (Bruker–Nonius, 2004); cell refinement: APEX2 (Bruker–Nonius, 2004); data reduction: SAINT-Plus (Bruker–Nonius, 2004); 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).

Figures top

	Fig. 1. ORTEP of the molecule with atoms represented as 30% probability ellipsoids.
	Fig. 2. Packing of molecules along the b axis.

r-2,c-6-Bis(3-methoxyphenyl)-t-3,t-5-dimethylpiperidin-4-one top

Crystal data top

C₂₁H₂₅NO₃	F(000) = 1456
M_r = 339.42	D_x = 1.177 Mg m⁻³
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 5862 reflections
a = 20.9885 (6) Å	θ = 2.4–22.6°
b = 9.7699 (2) Å	µ = 0.08 mm⁻¹
c = 19.8153 (5) Å	T = 298 K
β = 109.459 (2)°	Block, colourless
V = 3831.14 (17) Å³	0.25 × 0.23 × 0.22 mm
Z = 8

Data collection top

Bruker APEXII CCD area-detector diffractometer	4624 independent reflections
Radiation source: fine-focus sealed tube	2715 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
ϕ and ω scans	θ_max = 28.3°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 1999)	h = −27→27
T_min = 0.931, T_max = 0.983	k = −13→12
23076 measured reflections	l = −26→23

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.163	H atoms treated by a mixture of independent and constrained refinement
S = 0.92	w = 1/[σ²(F_o²) + (0.1P)² + 0.5P] where P = (F_o² + 2F_c²)/3
4624 reflections	(Δ/σ)_max < 0.001
239 parameters	Δρ_max = 0.12 e Å⁻³
1 restraint	Δρ_min = −0.14 e Å⁻³

Crystal data top

C₂₁H₂₅NO₃	V = 3831.14 (17) Å³
M_r = 339.42	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 20.9885 (6) Å	µ = 0.08 mm⁻¹
b = 9.7699 (2) Å	T = 298 K
c = 19.8153 (5) Å	0.25 × 0.23 × 0.22 mm
β = 109.459 (2)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	4624 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 1999)	2715 reflections with I > 2σ(I)
T_min = 0.931, T_max = 0.983	R_int = 0.031
23076 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	1 restraint
wR(F²) = 0.163	H atoms treated by a mixture of independent and constrained refinement
S = 0.92	Δρ_max = 0.12 e Å⁻³
4624 reflections	Δρ_min = −0.14 e Å⁻³
239 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	Occ. (<1)
C1	0.34428 (7)	0.63001 (15)	0.18001 (8)	0.0440 (4)
H1	0.3033	0.6627	0.1881	0.053*
C2	0.32387 (8)	0.52388 (16)	0.11928 (8)	0.0477 (4)
H2	0.3651	0.4956	0.1101	0.057*
C3	0.29531 (8)	0.39913 (18)	0.14380 (9)	0.0548 (4)
C4	0.33555 (7)	0.33955 (15)	0.21586 (8)	0.0461 (4)
H4	0.3776	0.3020	0.2122	0.055*
C5	0.35427 (7)	0.45552 (15)	0.27161 (8)	0.0425 (4)
H5	0.3127	0.4922	0.2767	0.051*
C6	0.38064 (8)	0.75142 (15)	0.16328 (8)	0.0456 (4)
C7	0.44600 (8)	0.73763 (15)	0.16225 (8)	0.0445 (4)
H7	0.4668	0.6523	0.1703	0.053*
C8	0.48077 (8)	0.84985 (17)	0.14930 (8)	0.0499 (4)
C9	0.44996 (11)	0.97624 (18)	0.13621 (11)	0.0715 (6)
H9	0.4730	1.0519	0.1276	0.086*
C10	0.38482 (12)	0.9890 (2)	0.13608 (13)	0.0872 (7)
H10	0.3637	1.0740	0.1266	0.105*
C11	0.35003 (10)	0.87908 (19)	0.14962 (11)	0.0712 (6)
H11	0.3060	0.8902	0.1496	0.085*
C12	0.27530 (10)	0.5817 (2)	0.04956 (10)	0.0764 (6)
H12A	0.2658	0.5130	0.0129	0.115*
H12B	0.2955	0.6597	0.0353	0.115*
H12C	0.2340	0.6089	0.0566	0.115*
C13	0.29752 (10)	0.22367 (18)	0.23642 (11)	0.0678 (5)
H13A	0.2563	0.2582	0.2408	0.102*
H13B	0.3249	0.1853	0.2813	0.102*
H13C	0.2873	0.1541	0.2001	0.102*
C14	0.39959 (8)	0.40590 (15)	0.34391 (8)	0.0461 (4)
C15	0.37474 (10)	0.3865 (2)	0.39968 (10)	0.0731 (6)
H15	0.3298	0.4061	0.3934	0.088*
C16	0.41662 (12)	0.3379 (3)	0.46462 (11)	0.0924 (8)
H16	0.3991	0.3236	0.5014	0.111*
C17	0.48319 (11)	0.3104 (2)	0.47607 (10)	0.0742 (6)
H17	0.5109	0.2784	0.5203	0.089*
C18	0.50881 (8)	0.33063 (16)	0.42127 (8)	0.0516 (4)
C19	0.46682 (7)	0.37783 (15)	0.35542 (8)	0.0453 (4)
H19	0.4843	0.3908	0.3185	0.054*
C20	0.58679 (12)	0.9383 (3)	0.14770 (15)	0.0956 (7)
H20A	0.5679	0.9847	0.1027	0.143*
H20B	0.6315	0.9069	0.1527	0.143*
H20C	0.5889	1.0000	0.1860	0.143*
C21	0.62095 (10)	0.2629 (2)	0.49353 (11)	0.0866 (7)
H21A	0.6201	0.3258	0.5305	0.130*
H21B	0.6657	0.2595	0.4907	0.130*
H21C	0.6082	0.1734	0.5045	0.130*
H1A	0.4028 (8)	0.6278 (19)	0.2787 (10)	0.056 (5)*
N1	0.38767 (6)	0.56426 (13)	0.24572 (7)	0.0424 (3)
O1	0.54531 (6)	0.82403 (13)	0.15007 (6)	0.0624 (4)
O2A	0.2376 (3)	0.3574 (6)	0.1104 (2)	0.0878 (14)	0.760 (15)
O2B	0.2601 (7)	0.3246 (17)	0.1015 (7)	0.0878 (14)	0.241 (15)
O3	0.57452 (6)	0.30761 (13)	0.42644 (6)	0.0666 (4)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0379 (8)	0.0520 (8)	0.0419 (9)	0.0083 (6)	0.0128 (7)	0.0066 (7)
C2	0.0397 (8)	0.0609 (10)	0.0385 (8)	−0.0020 (7)	0.0078 (7)	0.0035 (7)
C3	0.0445 (9)	0.0689 (11)	0.0451 (10)	−0.0112 (8)	0.0068 (8)	−0.0042 (8)
C4	0.0391 (8)	0.0486 (8)	0.0500 (9)	−0.0030 (6)	0.0141 (7)	−0.0003 (7)
C5	0.0369 (8)	0.0504 (8)	0.0408 (8)	0.0042 (6)	0.0135 (7)	0.0057 (7)
C6	0.0491 (9)	0.0479 (9)	0.0378 (8)	0.0066 (7)	0.0118 (7)	0.0070 (7)
C7	0.0465 (9)	0.0443 (8)	0.0388 (8)	0.0021 (6)	0.0090 (7)	0.0038 (6)
C8	0.0545 (10)	0.0541 (9)	0.0385 (9)	−0.0053 (7)	0.0121 (7)	−0.0006 (7)
C9	0.0908 (15)	0.0483 (10)	0.0834 (14)	−0.0055 (9)	0.0396 (12)	0.0099 (9)
C10	0.1054 (18)	0.0477 (11)	0.123 (2)	0.0209 (11)	0.0568 (16)	0.0256 (11)
C11	0.0696 (12)	0.0581 (11)	0.0941 (15)	0.0189 (9)	0.0382 (11)	0.0208 (10)
C12	0.0677 (12)	0.0969 (15)	0.0493 (11)	−0.0041 (11)	−0.0012 (10)	0.0147 (10)
C13	0.0672 (12)	0.0599 (11)	0.0748 (13)	−0.0141 (9)	0.0218 (10)	0.0068 (9)
C14	0.0486 (9)	0.0487 (8)	0.0406 (9)	0.0013 (7)	0.0145 (7)	0.0051 (7)
C15	0.0605 (11)	0.1109 (16)	0.0525 (11)	0.0134 (11)	0.0252 (10)	0.0182 (10)
C16	0.0858 (16)	0.148 (2)	0.0511 (12)	0.0181 (15)	0.0330 (12)	0.0295 (13)
C17	0.0761 (14)	0.0975 (15)	0.0408 (10)	0.0060 (11)	0.0085 (10)	0.0208 (10)
C18	0.0518 (10)	0.0504 (9)	0.0447 (10)	0.0002 (7)	0.0052 (8)	0.0068 (7)
C19	0.0481 (9)	0.0474 (8)	0.0384 (9)	−0.0018 (7)	0.0119 (7)	0.0058 (7)
C20	0.0824 (15)	0.0931 (16)	0.1168 (19)	−0.0398 (13)	0.0406 (15)	−0.0121 (14)
C21	0.0678 (13)	0.0993 (16)	0.0654 (14)	0.0113 (11)	−0.0141 (11)	0.0136 (11)
N1	0.0438 (7)	0.0441 (7)	0.0345 (7)	−0.0023 (5)	0.0066 (6)	0.0032 (6)
O1	0.0527 (7)	0.0679 (8)	0.0662 (8)	−0.0140 (5)	0.0191 (6)	0.0032 (6)
O2A	0.051 (2)	0.120 (2)	0.0707 (14)	−0.040 (2)	−0.0090 (14)	0.0095 (14)
O2B	0.051 (2)	0.120 (2)	0.0707 (14)	−0.040 (2)	−0.0090 (14)	0.0095 (14)
O3	0.0498 (7)	0.0787 (9)	0.0574 (8)	0.0069 (6)	−0.0005 (6)	0.0176 (6)

Geometric parameters (Å, º) top

C1—N1	1.4654 (19)	C12—H12A	0.9600
C1—C6	1.506 (2)	C12—H12B	0.9600
C1—C2	1.537 (2)	C12—H12C	0.9600
C1—H1	0.9800	C13—H13A	0.9600
C2—C3	1.508 (2)	C13—H13B	0.9600
C2—C12	1.526 (2)	C13—H13C	0.9600
C2—H2	0.9800	C14—C19	1.380 (2)
C3—O2B	1.169 (13)	C14—C15	1.383 (2)
C3—O2A	1.240 (4)	C15—C16	1.378 (3)
C3—C4	1.513 (2)	C15—H15	0.9300
C4—C13	1.517 (2)	C16—C17	1.366 (3)
C4—C5	1.539 (2)	C16—H16	0.9300
C4—H4	0.9800	C17—C18	1.377 (2)
C5—N1	1.4570 (18)	C17—H17	0.9300
C5—C14	1.511 (2)	C18—O3	1.3671 (19)
C5—H5	0.9800	C18—C19	1.388 (2)
C6—C7	1.385 (2)	C19—H19	0.9300
C6—C11	1.388 (2)	C20—O1	1.426 (2)
C7—C8	1.387 (2)	C20—H20A	0.9600
C7—H7	0.9300	C20—H20B	0.9600
C8—O1	1.3730 (19)	C20—H20C	0.9600
C8—C9	1.378 (2)	C21—O3	1.430 (2)
C9—C10	1.372 (3)	C21—H21A	0.9600
C9—H9	0.9300	C21—H21B	0.9600
C10—C11	1.374 (3)	C21—H21C	0.9600
C10—H10	0.9300	N1—H1A	0.881 (18)
C11—H11	0.9300

N1—C1—C6	109.30 (12)	C2—C12—H12A	109.5
N1—C1—C2	109.18 (12)	C2—C12—H12B	109.5
C6—C1—C2	112.85 (12)	H12A—C12—H12B	109.5
N1—C1—H1	108.5	C2—C12—H12C	109.5
C6—C1—H1	108.5	H12A—C12—H12C	109.5
C2—C1—H1	108.5	H12B—C12—H12C	109.5
C3—C2—C12	111.93 (14)	C4—C13—H13A	109.5
C3—C2—C1	109.26 (12)	C4—C13—H13B	109.5
C12—C2—C1	112.75 (14)	H13A—C13—H13B	109.5
C3—C2—H2	107.6	C4—C13—H13C	109.5
C12—C2—H2	107.6	H13A—C13—H13C	109.5
C1—C2—H2	107.6	H13B—C13—H13C	109.5
O2B—C3—O2A	30.7 (7)	C19—C14—C15	118.53 (15)
O2B—C3—C2	119.8 (7)	C19—C14—C5	120.44 (13)
O2A—C3—C2	121.1 (2)	C15—C14—C5	121.03 (14)
O2B—C3—C4	117.2 (7)	C16—C15—C14	120.02 (17)
O2A—C3—C4	121.1 (2)	C16—C15—H15	120.0
C2—C3—C4	117.27 (13)	C14—C15—H15	120.0
C3—C4—C13	111.25 (13)	C17—C16—C15	121.45 (17)
C3—C4—C5	108.85 (13)	C17—C16—H16	119.3
C13—C4—C5	112.82 (13)	C15—C16—H16	119.3
C3—C4—H4	107.9	C16—C17—C18	119.18 (17)
C13—C4—H4	107.9	C16—C17—H17	120.4
C5—C4—H4	107.9	C18—C17—H17	120.4
N1—C5—C14	110.05 (12)	O3—C18—C17	124.51 (15)
N1—C5—C4	108.76 (11)	O3—C18—C19	115.71 (14)
C14—C5—C4	111.95 (12)	C17—C18—C19	119.78 (16)
N1—C5—H5	108.7	C14—C19—C18	121.04 (14)
C14—C5—H5	108.7	C14—C19—H19	119.5
C4—C5—H5	108.7	C18—C19—H19	119.5
C7—C6—C11	118.74 (15)	O1—C20—H20A	109.5
C7—C6—C1	120.24 (13)	O1—C20—H20B	109.5
C11—C6—C1	121.02 (14)	H20A—C20—H20B	109.5
C6—C7—C8	120.69 (14)	O1—C20—H20C	109.5
C6—C7—H7	119.7	H20A—C20—H20C	109.5
C8—C7—H7	119.7	H20B—C20—H20C	109.5
O1—C8—C9	124.48 (15)	O3—C21—H21A	109.5
O1—C8—C7	115.50 (14)	O3—C21—H21B	109.5
C9—C8—C7	120.02 (16)	H21A—C21—H21B	109.5
C10—C9—C8	119.12 (16)	O3—C21—H21C	109.5
C10—C9—H9	120.4	H21A—C21—H21C	109.5
C8—C9—H9	120.4	H21B—C21—H21C	109.5
C9—C10—C11	121.50 (17)	C5—N1—C1	113.77 (12)
C9—C10—H10	119.3	C5—N1—H1A	110.5 (11)
C11—C10—H10	119.3	C1—N1—H1A	108.3 (11)
C10—C11—C6	119.93 (17)	C8—O1—C20	117.83 (15)
C10—C11—H11	120.0	C18—O3—C21	118.55 (15)
C6—C11—H11	120.0

N1—C1—C2—C3	51.68 (16)	O1—C8—C9—C10	179.28 (18)
C6—C1—C2—C3	173.44 (13)	C7—C8—C9—C10	−0.1 (3)
N1—C1—C2—C12	176.82 (13)	C8—C9—C10—C11	0.9 (4)
C6—C1—C2—C12	−61.42 (17)	C9—C10—C11—C6	−0.5 (4)
C12—C2—C3—O2B	32.9 (11)	C7—C6—C11—C10	−0.6 (3)
C1—C2—C3—O2B	158.5 (11)	C1—C6—C11—C10	178.52 (18)
C12—C2—C3—O2A	−2.9 (5)	N1—C5—C14—C19	−46.64 (19)
C1—C2—C3—O2A	122.7 (5)	C4—C5—C14—C19	74.44 (17)
C12—C2—C3—C4	−174.39 (15)	N1—C5—C14—C15	133.92 (17)
C1—C2—C3—C4	−48.78 (18)	C4—C5—C14—C15	−105.00 (18)
O2B—C3—C4—C13	−32.1 (10)	C19—C14—C15—C16	−1.0 (3)
O2A—C3—C4—C13	3.0 (5)	C5—C14—C15—C16	178.4 (2)
C2—C3—C4—C13	174.50 (15)	C14—C15—C16—C17	1.2 (4)
O2B—C3—C4—C5	−157.0 (10)	C15—C16—C17—C18	−0.6 (4)
O2A—C3—C4—C5	−121.9 (5)	C16—C17—C18—O3	179.6 (2)
C2—C3—C4—C5	49.58 (18)	C16—C17—C18—C19	−0.3 (3)
C3—C4—C5—N1	−53.41 (15)	C15—C14—C19—C18	0.2 (2)
C13—C4—C5—N1	−177.41 (13)	C5—C14—C19—C18	−179.21 (14)
C3—C4—C5—C14	−175.24 (12)	O3—C18—C19—C14	−179.43 (14)
C13—C4—C5—C14	60.77 (17)	C17—C18—C19—C14	0.4 (3)
N1—C1—C6—C7	50.27 (18)	C14—C5—N1—C1	−172.98 (12)
C2—C1—C6—C7	−71.42 (18)	C4—C5—N1—C1	64.05 (16)
N1—C1—C6—C11	−128.84 (17)	C6—C1—N1—C5	172.93 (12)
C2—C1—C6—C11	109.47 (18)	C2—C1—N1—C5	−63.19 (15)
C11—C6—C7—C8	1.3 (2)	C9—C8—O1—C20	9.7 (3)
C1—C6—C7—C8	−177.79 (14)	C7—C8—O1—C20	−170.90 (17)
C6—C7—C8—O1	179.56 (13)	C17—C18—O3—C21	−1.7 (3)
C6—C7—C8—C9	−1.0 (2)	C19—C18—O3—C21	178.11 (16)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱ	0.881 (18)	2.414 (19)	3.2784 (18)	167.1 (15)
C2—H2···O3ⁱ	0.98	2.47	3.335 (2)	146

Symmetry code: (i) −x+1, y, −z+1/2.

Experimental details

Crystal data
Chemical formula	C₂₁H₂₅NO₃
M_r	339.42
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	298
a, b, c (Å)	20.9885 (6), 9.7699 (2), 19.8153 (5)
β (°)	109.459 (2)
V (Å³)	3831.14 (17)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.25 × 0.23 × 0.22

Data collection
Diffractometer	Bruker APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 1999)
T_min, T_max	0.931, 0.983
No. of measured, independent and observed [I > 2σ(I)] reflections	23076, 4624, 2715
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.163, 0.92
No. of reflections	4624
No. of parameters	239
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.12, −0.14

Computer programs: APEX2 (Bruker–Nonius, 2004), SAINT-Plus (Bruker–Nonius, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O1ⁱ	0.881 (18)	2.414 (19)	3.2784 (18)	167.1 (15)
C2—H2···O3ⁱ	0.98	2.47	3.335 (2)	146

Symmetry code: (i) −x+1, y, −z+1/2.

Acknowledgements

This research was supported by the second stage of BK 21 program and Pukyong National University under the 2008 Postdoc program. The authors acknowledge the Department of Chemistry, IIT Madras, for the X-ray data collection.

References

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