(2S,6S)-1-Methyl-2,6-trans-distyryl­piperidinium chloride

Zheng, G.; Parkin, S.; Dwoskin, L.P.; Crooks, P.A.

doi:10.1107/S1600536809049587

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 66| Part 1| January 2010| Page o78

doi:10.1107/S1600536809049587

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(2S,6S)-1-Methyl-2,6-trans-distyrylpiperidinium chloride

Guangrong Zheng,^a Sean Parkin,^b Linda P. Dwoskin ^a and Peter A. Crooks ^a ^*

^aDepartment of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA, and ^bDepartment of Chemistry, University of Kentucky, Lexington, KY 40536, USA
^*Correspondence e-mail: pcrooks@email.uky.edu

(Received 18 November 2009; accepted 19 November 2009; online 9 December 2009)

In the crystal structure of the title compound, C₂₂H₂₆N⁺·Cl⁻, the piperidine ring is in a chair conformation and the two styryl groups are in axial and equatorial positions. The molecule has a hydrogen bond between the NH group and the chloride anion.

Related literature

The title compound is a des-oxygen derivative of epimerized (−)-lobeline (Zheng et al., 2005 ).

Experimental

Crystal data

C₂₂H₂₆N⁺·Cl⁻
M_r = 339.89
Orthorhombic, P 2₁ 2₁ 2₁
a = 9.9355 (4) Å
b = 12.3075 (5) Å
c = 15.8299 (7) Å
V = 1935.70 (14) Å³
Z = 4
Mo Kα radiation
μ = 0.20 mm⁻¹
T = 173 K
0.38 × 0.28 × 0.08 mm

Data collection

Nonius KappaCCD diffractometer
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997 ) T_min = 0.930, T_max = 0.984
11921 measured reflections
3416 independent reflections
2957 reflections with I > 2σ(I)
R_int = 0.065

Refinement

R[F² > 2σ(F²)] = 0.054
wR(F²) = 0.091
S = 1.11
3416 reflections
218 parameters
H-atom parameters constrained
Δρ_max = 0.45 e Å⁻³
Δρ_min = −0.26 e Å⁻³
Absolute structure: Flack (1983 ), 1457 Friedel pairs
Flack parameter: 0.06 (7)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯Clⁱ	0.93	2.10	3.027 (2)	176
Symmetry code: (i) $[-x+1, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ .

Data collection: COLLECT (Nonius, 1998 ); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in Siemens SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 and local procedures.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809049587/hg2599sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809049587/hg2599Isup2.hkl

checkCIF report

Comment top

The title compound is a des-oxygen derivative of epimerized (-)-lobeline (Zheng et al., 2005). The molecular structure is illustrated in Fig. 1. The piperidine ring of the molecule is in the chair conformation and the N-methyl group is bonded equatorially to the piperidine ring. The N atom has an axial H atom that is hydrogen bonded to the chloride anion (HN..Cl = 3.027 (2) Å). One styryl group is attached equatorially to the piperidine ring and the other styryl group is pseudo-axial, with C15—C2—N1 [111.67 (18)°] and C15—C2—C3 [113.7 (2)°] bond angles slightly different from the ideal 109.5°. The piperidine ring is not mirror symmetric, as indicated by unequal bond lengths and angles (Table 1). The double bond and phenyl ring of the styryl side chain are not coplanar, as evidenced by the C15—C16—C17—C18 and C7—C8—C9—C14 torsion angles, -165.4 (3)° and -169.0 (2)°, respectively.

Related literature top

The title compound is a des-oxygen derivative of epimerized (-)-lobeline (Zheng et al., 2005).

Experimental top

The title compound was prepared from (-)-lobeline (Zheng et al., 2005). Crystals suitable for X-ray diffraction studies were obtained by slow recrystallization from a solution in methanol and diethyl ether.

Computing details top

Data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO-SMN (Otwinowski & Minor, 1997); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in Siemens SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELX97 (Sheldrick, 2008) and local procedures.

Figures top

Fig. 1. A view of the molecule. Displacement ellipsoids are drawn at the 50% probability level.

(2S,6S)-1-Methyl-2,6-trans-distyrylpiperidinium chloride top

Crystal data top

C₂₂H₂₆N⁺·Cl⁻	F(000) = 728
M_r = 339.89	D_x = 1.166 Mg m⁻³
Orthorhombic, P2₁2₁2₁	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 21849 reflections
a = 9.9355 (4) Å	θ = 1.0–27.5°
b = 12.3075 (5) Å	µ = 0.20 mm⁻¹
c = 15.8299 (7) Å	T = 173 K
V = 1935.70 (14) Å³	Irregular plates, colourless
Z = 4	0.38 × 0.28 × 0.08 mm

Data collection top

Nonius KappaCCD diffractometer	3416 independent reflections
Radiation source: fine-focus sealed tube	2957 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.065
Detector resolution: 18 pixels mm^-1	θ_max = 25.0°, θ_min = 2.1°
ω scans at fixed χ = 55°	h = −11→11
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997)	k = −14→14
T_min = 0.930, T_max = 0.984	l = −18→18
11921 measured reflections

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)] = 0.054	H-atom parameters constrained
wR(F²) = 0.091	w = 1/[σ²(F_o²) + (0.0332P)² + 0.1721P] where P = (F_o² + 2F_c²)/3
S = 1.11	(Δ/σ)_max = 0.001
3416 reflections	Δρ_max = 0.45 e Å⁻³
218 parameters	Δρ_min = −0.26 e Å⁻³
0 restraints	Absolute structure: Flack (1983), 1457 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.06 (7)

Crystal data top

C₂₂H₂₆N⁺·Cl⁻	V = 1935.70 (14) Å³
M_r = 339.89	Z = 4
Orthorhombic, P2₁2₁2₁	Mo Kα radiation
a = 9.9355 (4) Å	µ = 0.20 mm⁻¹
b = 12.3075 (5) Å	T = 173 K
c = 15.8299 (7) Å	0.38 × 0.28 × 0.08 mm

Data collection top

Nonius KappaCCD diffractometer	3416 independent reflections
Absorption correction: multi-scan (SCALEPACK; Otwinowski & Minor, 1997)	2957 reflections with I > 2σ(I)
T_min = 0.930, T_max = 0.984	R_int = 0.065
11921 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.054	H-atom parameters constrained
wR(F²) = 0.091	Δρ_max = 0.45 e Å⁻³
S = 1.11	Δρ_min = −0.26 e Å⁻³
3416 reflections	Absolute structure: Flack (1983), 1457 Friedel pairs
218 parameters	Absolute structure parameter: 0.06 (7)
0 restraints

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
Cl	0.49125 (6)	1.13417 (4)	0.35616 (4)	0.03556 (19)
N1	0.44499 (17)	0.82481 (15)	0.25784 (13)	0.0275 (5)
H1	0.4661	0.7643	0.2253	0.033*
C1	0.4017 (3)	0.9121 (2)	0.19752 (16)	0.0358 (7)
H1A	0.3144	0.8928	0.1729	0.054*
H1B	0.4687	0.9192	0.1524	0.054*
H1C	0.3938	0.9812	0.2278	0.054*
C2	0.3304 (2)	0.79138 (19)	0.31510 (17)	0.0305 (6)
H2	0.2579	0.7607	0.2783	0.037*
C3	0.3774 (3)	0.7007 (2)	0.37336 (17)	0.0372 (7)
H3A	0.3035	0.6812	0.4125	0.045*
H3B	0.3991	0.6356	0.3392	0.045*
C4	0.5004 (3)	0.7336 (2)	0.42414 (16)	0.0395 (7)
H4A	0.4780	0.7958	0.4612	0.047*
H4B	0.5298	0.6724	0.4602	0.047*
C5	0.6127 (2)	0.76520 (19)	0.36400 (16)	0.0331 (6)
H5A	0.6390	0.7008	0.3304	0.040*
H5B	0.6920	0.7884	0.3972	0.040*
C6	0.5726 (2)	0.85631 (19)	0.30435 (15)	0.0272 (6)
H6	0.5545	0.9232	0.3383	0.033*
C7	0.6841 (2)	0.87992 (19)	0.24306 (15)	0.0292 (6)
H7	0.7039	0.8283	0.2002	0.035*
C8	0.7558 (2)	0.9709 (2)	0.24688 (15)	0.0283 (6)
H8	0.7260	1.0241	0.2861	0.034*
C9	0.8759 (2)	0.9986 (2)	0.19738 (15)	0.0281 (6)
C10	0.9516 (2)	1.0897 (2)	0.22012 (17)	0.0342 (7)
H10	0.9237	1.1327	0.2667	0.041*
C11	1.0659 (2)	1.1182 (2)	0.17623 (18)	0.0391 (7)
H11	1.1164	1.1800	0.1932	0.047*
C12	1.1074 (3)	1.0578 (2)	0.10788 (17)	0.0444 (8)
H12	1.1859	1.0780	0.0775	0.053*
C13	1.0347 (3)	0.9682 (2)	0.08396 (17)	0.0460 (8)
H13	1.0629	0.9266	0.0366	0.055*
C14	0.9202 (3)	0.9378 (2)	0.12838 (17)	0.0419 (7)
H14	0.8715	0.8750	0.1116	0.050*
C15	0.2714 (2)	0.88730 (18)	0.36100 (16)	0.0278 (6)
H15	0.3300	0.9378	0.3875	0.033*
C16	0.1402 (2)	0.90289 (19)	0.36523 (17)	0.0307 (6)
H16	0.0856	0.8520	0.3359	0.037*
C17	0.0685 (2)	0.9906 (2)	0.41046 (14)	0.0257 (6)
C18	−0.0696 (2)	0.9803 (2)	0.42416 (15)	0.0312 (6)
H18	−0.1147	0.9167	0.4054	0.037*
C19	−0.1417 (3)	1.0608 (2)	0.46452 (16)	0.0383 (7)
H19	−0.2359	1.0527	0.4729	0.046*
C20	−0.0774 (3)	1.1519 (2)	0.49227 (17)	0.0390 (7)
H20	−0.1269	1.2071	0.5204	0.047*
C21	0.0595 (3)	1.1644 (2)	0.47978 (16)	0.0342 (7)
H21	0.1037	1.2278	0.4998	0.041*
C22	0.1322 (3)	1.0848 (2)	0.43814 (15)	0.0290 (6)
H22	0.2258	1.0945	0.4284	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl	0.0428 (4)	0.0231 (3)	0.0408 (4)	−0.0033 (3)	0.0079 (3)	−0.0019 (3)
N1	0.0250 (11)	0.0208 (11)	0.0369 (12)	0.0017 (9)	0.0023 (10)	−0.0077 (10)
C1	0.0337 (16)	0.0357 (15)	0.0379 (16)	0.0067 (13)	−0.0034 (13)	−0.0001 (14)
C2	0.0190 (14)	0.0247 (14)	0.0478 (16)	−0.0070 (11)	0.0024 (13)	−0.0055 (13)
C3	0.0334 (16)	0.0283 (15)	0.0500 (18)	−0.0045 (12)	0.0089 (14)	0.0034 (14)
C4	0.0414 (16)	0.0329 (14)	0.0442 (17)	0.0019 (15)	0.0055 (16)	0.0147 (13)
C5	0.0243 (14)	0.0306 (15)	0.0445 (17)	0.0002 (12)	−0.0047 (13)	0.0062 (14)
C6	0.0194 (13)	0.0244 (14)	0.0377 (15)	−0.0057 (12)	−0.0040 (12)	−0.0056 (13)
C7	0.0256 (13)	0.0319 (15)	0.0301 (15)	0.0050 (13)	−0.0009 (12)	−0.0023 (13)
C8	0.0236 (14)	0.0294 (15)	0.0319 (15)	0.0007 (12)	−0.0023 (12)	−0.0012 (13)
C9	0.0218 (14)	0.0360 (16)	0.0264 (14)	0.0004 (12)	−0.0029 (12)	0.0050 (13)
C10	0.0288 (15)	0.0325 (15)	0.0412 (16)	0.0026 (12)	−0.0026 (13)	0.0033 (13)
C11	0.0294 (15)	0.0356 (17)	0.0523 (19)	−0.0086 (13)	−0.0001 (14)	0.0098 (16)
C12	0.0300 (16)	0.061 (2)	0.0427 (18)	−0.0069 (16)	0.0042 (14)	0.0142 (16)
C13	0.0379 (18)	0.066 (2)	0.0339 (17)	−0.0039 (16)	0.0074 (14)	−0.0072 (15)
C14	0.0347 (16)	0.0530 (18)	0.0380 (18)	−0.0100 (14)	−0.0044 (14)	−0.0036 (16)
C15	0.0241 (14)	0.0235 (14)	0.0359 (15)	−0.0025 (11)	0.0007 (12)	−0.0038 (12)
C16	0.0280 (15)	0.0262 (14)	0.0379 (15)	−0.0046 (11)	−0.0065 (13)	−0.0035 (13)
C17	0.0231 (14)	0.0276 (15)	0.0265 (14)	0.0052 (12)	−0.0040 (11)	0.0030 (12)
C18	0.0238 (15)	0.0347 (16)	0.0350 (15)	−0.0033 (13)	−0.0051 (12)	−0.0003 (13)
C19	0.0237 (15)	0.0502 (19)	0.0410 (18)	0.0055 (14)	0.0035 (13)	−0.0038 (15)
C20	0.0382 (18)	0.0449 (19)	0.0338 (16)	0.0115 (15)	0.0034 (13)	−0.0065 (15)
C21	0.0378 (17)	0.0297 (17)	0.0352 (16)	−0.0010 (13)	0.0011 (13)	−0.0052 (13)
C22	0.0224 (14)	0.0335 (15)	0.0311 (15)	−0.0016 (12)	0.0019 (12)	0.0009 (13)

Geometric parameters (Å, º) top

N1—C1	1.500 (3)	C9—C10	1.397 (3)
N1—C2	1.512 (3)	C10—C11	1.377 (3)
N1—C6	1.517 (3)	C10—H10	0.9500
N1—H1	0.9300	C11—C12	1.376 (3)
C1—H1A	0.9800	C11—H11	0.9500
C1—H1B	0.9800	C12—C13	1.371 (4)
C1—H1C	0.9800	C12—H12	0.9500
C2—C15	1.505 (3)	C13—C14	1.389 (3)
C2—C3	1.522 (3)	C13—H13	0.9500
C2—H2	1.0000	C14—H14	0.9500
C3—C4	1.518 (3)	C15—C16	1.320 (3)
C3—H3A	0.9900	C15—H15	0.9500
C3—H3B	0.9900	C16—C17	1.478 (3)
C4—C5	1.517 (3)	C16—H16	0.9500
C4—H4A	0.9900	C17—C22	1.392 (3)
C4—H4B	0.9900	C17—C18	1.394 (3)
C5—C6	1.519 (3)	C18—C19	1.380 (3)
C5—H5A	0.9900	C18—H18	0.9500
C5—H5B	0.9900	C19—C20	1.363 (4)
C6—C7	1.501 (3)	C19—H19	0.9500
C6—H6	1.0000	C20—C21	1.383 (3)
C7—C8	1.329 (3)	C20—H20	0.9500
C7—H7	0.9500	C21—C22	1.384 (3)
C8—C9	1.468 (3)	C21—H21	0.9500
C8—H8	0.9500	C22—H22	0.9500
C9—C14	1.395 (3)

C1—N1—C2	111.13 (18)	C7—C8—C9	127.4 (2)
C1—N1—C6	111.45 (18)	C7—C8—H8	116.3
C2—N1—C6	114.09 (19)	C9—C8—H8	116.3
C1—N1—H1	106.5	C14—C9—C10	117.5 (2)
C2—N1—H1	106.5	C14—C9—C8	123.4 (2)
C6—N1—H1	106.5	C10—C9—C8	119.1 (2)
N1—C1—H1A	109.5	C11—C10—C9	121.2 (3)
N1—C1—H1B	109.5	C11—C10—H10	119.4
H1A—C1—H1B	109.5	C9—C10—H10	119.4
N1—C1—H1C	109.5	C12—C11—C10	120.4 (3)
H1A—C1—H1C	109.5	C12—C11—H11	119.8
H1B—C1—H1C	109.5	C10—C11—H11	119.8
C15—C2—N1	111.67 (18)	C13—C12—C11	119.6 (3)
C15—C2—C3	113.7 (2)	C13—C12—H12	120.2
N1—C2—C3	109.39 (19)	C11—C12—H12	120.2
C15—C2—H2	107.2	C12—C13—C14	120.6 (3)
N1—C2—H2	107.2	C12—C13—H13	119.7
C3—C2—H2	107.2	C14—C13—H13	119.7
C4—C3—C2	111.81 (19)	C13—C14—C9	120.7 (3)
C4—C3—H3A	109.3	C13—C14—H14	119.7
C2—C3—H3A	109.3	C9—C14—H14	119.7
C4—C3—H3B	109.3	C16—C15—C2	121.6 (2)
C2—C3—H3B	109.3	C16—C15—H15	119.2
H3A—C3—H3B	107.9	C2—C15—H15	119.2
C5—C4—C3	109.2 (2)	C15—C16—C17	127.4 (2)
C5—C4—H4A	109.8	C15—C16—H16	116.3
C3—C4—H4A	109.8	C17—C16—H16	116.3
C5—C4—H4B	109.8	C22—C17—C18	118.3 (2)
C3—C4—H4B	109.8	C22—C17—C16	122.8 (2)
H4A—C4—H4B	108.3	C18—C17—C16	118.9 (2)
C4—C5—C6	112.74 (19)	C19—C18—C17	121.2 (3)
C4—C5—H5A	109.0	C19—C18—H18	119.4
C6—C5—H5A	109.0	C17—C18—H18	119.4
C4—C5—H5B	109.0	C20—C19—C18	119.7 (2)
C6—C5—H5B	109.0	C20—C19—H19	120.1
H5A—C5—H5B	107.8	C18—C19—H19	120.1
C7—C6—N1	110.65 (18)	C19—C20—C21	120.5 (3)
C7—C6—C5	110.60 (19)	C19—C20—H20	119.8
N1—C6—C5	109.39 (19)	C21—C20—H20	119.8
C7—C6—H6	108.7	C20—C21—C22	120.2 (3)
N1—C6—H6	108.7	C20—C21—H21	119.9
C5—C6—H6	108.7	C22—C21—H21	119.9
C8—C7—C6	122.0 (2)	C21—C22—C17	120.1 (2)
C8—C7—H7	119.0	C21—C22—H22	119.9
C6—C7—H7	119.0	C17—C22—H22	119.9

C1—N1—C2—C15	−54.9 (3)	C8—C9—C10—C11	179.3 (2)
C6—N1—C2—C15	72.2 (2)	C9—C10—C11—C12	0.7 (4)
C1—N1—C2—C3	178.35 (18)	C10—C11—C12—C13	−0.4 (4)
C6—N1—C2—C3	−54.6 (3)	C11—C12—C13—C14	−0.4 (4)
C15—C2—C3—C4	−69.2 (3)	C12—C13—C14—C9	0.9 (4)
N1—C2—C3—C4	56.4 (3)	C10—C9—C14—C13	−0.6 (4)
C2—C3—C4—C5	−58.0 (3)	C8—C9—C14—C13	180.0 (2)
C3—C4—C5—C6	57.4 (3)	N1—C2—C15—C16	133.2 (3)
C1—N1—C6—C7	−57.5 (2)	C3—C2—C15—C16	−102.5 (3)
C2—N1—C6—C7	175.62 (18)	C2—C15—C16—C17	177.6 (2)
C1—N1—C6—C5	−179.60 (19)	C15—C16—C17—C22	16.4 (4)
C2—N1—C6—C5	53.5 (2)	C15—C16—C17—C18	−165.4 (3)
C4—C5—C6—C7	−176.7 (2)	C22—C17—C18—C19	−0.4 (4)
C4—C5—C6—N1	−54.6 (3)	C16—C17—C18—C19	−178.7 (2)
N1—C6—C7—C8	129.0 (2)	C17—C18—C19—C20	−0.5 (4)
C5—C6—C7—C8	−109.6 (3)	C18—C19—C20—C21	0.4 (4)
C6—C7—C8—C9	172.7 (2)	C19—C20—C21—C22	0.6 (4)
C7—C8—C9—C14	10.4 (4)	C20—C21—C22—C17	−1.5 (4)
C7—C8—C9—C10	−169.0 (2)	C18—C17—C22—C21	1.4 (4)
C14—C9—C10—C11	−0.2 (3)	C16—C17—C22—C21	179.7 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Clⁱ	0.93	2.10	3.027 (2)	176

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

Experimental details

Crystal data
Chemical formula	C₂₂H₂₆N⁺·Cl⁻
M_r	339.89
Crystal system, space group	Orthorhombic, P2₁2₁2₁
Temperature (K)	173
a, b, c (Å)	9.9355 (4), 12.3075 (5), 15.8299 (7)
V (Å³)	1935.70 (14)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.20
Crystal size (mm)	0.38 × 0.28 × 0.08

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	Multi-scan (SCALEPACK; Otwinowski & Minor, 1997)
T_min, T_max	0.930, 0.984
No. of measured, independent and observed [I > 2σ(I)] reflections	11921, 3416, 2957
R_int	0.065
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.054, 0.091, 1.11
No. of reflections	3416
No. of parameters	218
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.45, −0.26
Absolute structure	Flack (1983), 1457 Friedel pairs
Absolute structure parameter	0.06 (7)

Computer programs: COLLECT (Nonius, 1998), SCALEPACK (Otwinowski & Minor, 1997), DENZO-SMN (Otwinowski & Minor, 1997), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in Siemens SHELXTL (Sheldrick, 2008), SHELX97 (Sheldrick, 2008) and local procedures.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···Clⁱ	0.93	2.10	3.027 (2)	175.7

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

Acknowledgements

This research was supported by National Institute of Health grants DA13519 and DA00399.

References

Flack, H. D. (1983). Acta Cryst. A39, 876–881. CrossRef CAS Web of Science IUCr Journals Google Scholar
Nonius (1998). COLLECT. Nonius BV, Delft, The Netherlands. Google Scholar
Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307–326. New York: Academic Press. Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Zheng, G., Dwoskin, L. P., Deaciuc, A. G., Norrholm, S. D. & Crooks, P. A. (2005). J. Med. Chem. pp. 5551–5560. Web of Science CrossRef Google Scholar