(R)-(+)-3-Hydr­oxy-2-methoxy­carbonyl-8-methyl-8-azoniabicyclo­[3.2.1]octane l-bitartrate

Jian-Bing Yu; Shuang-Wei Chen; Guo-Rong Zheng; Li-Yan Dai

doi:10.1107/S1600536808023532

. 2008 Jul 31;64(Pt 8):o1653. doi: 10.1107/S1600536808023532

(R)-(+)-3-Hydroxy-2-methoxycarbonyl-8-methyl-8-azoniabicyclo[3.2.1]octane l-bitartrate

Jian-Bing Yu ^a, Shuang-Wei Chen ^b, Guo-Rong Zheng ^b, Li-Yan Dai ^a,^*

PMCID: PMC2962227 PMID: 21203339

Abstract

(RS)-(±)-2-Methoxycarbonyl-3-tropinone is an important intermediate for the preparation of cocaine and its derivatives. The molecule in the title compound, C₁₀H₁₆NO₃ ⁺·C₄H₅O₆ ⁻, is present as the enol tautomer. The six-membered ring adopts a half boat conformation, and the five-membered ring a slightly distorted envelope conformation. There are intra- and intermolecular hydrogen bonds involving the hydroxyl, carboxyl groups and quaternary ammonium groups.

Related literature

For related literature, see: Findlay (1957 ▶); Meltzer et al. (1994 ▶).

Experimental

Crystal data

C₁₀H₁₆NO₃ ⁺·C₄H₅O₆ ⁻
M _r = 347.32
Monoclinic,
a = 6.5030 (10) Å
b = 15.914 (3) Å
c = 7.6626 (12) Å
β = 96.497 (3)°
V = 787.9 (2) Å³
Z = 2
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 293 (2) K
0.50 × 0.49 × 0.37 mm

Data collection

SMART 1K CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2002 ▶) T _min = 0.936, T _max = 0.961
4145 measured reflections
1522 independent reflections
1460 reflections with I > 2σ(I)
R _int = 0.082

Refinement

R[F ² > 2σ(F ²)] = 0.064
wR(F ²) = 0.154
S = 1.05
1522 reflections
226 parameters
2 restraints
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.38 e Å⁻³
Δρ_min = −0.35 e Å⁻³

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and publCIF (Westrip, 2008 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808023532/rk2093sup1.cif

e-64-o1653-sup1.cif^{(20.1KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808023532/rk2093Isup2.hkl

e-64-o1653-Isup2.hkl^{(75KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1A⋯O2	0.82	1.89	2.600 (4)	145
O7—H7⋯O9	0.82	2.06	2.562 (4)	120
N1—H1⋯O8ⁱ	0.954 (19)	1.82 (2)	2.724 (4)	158 (4)
O6—H6A⋯O2ⁱⁱ	0.82	2.58	3.182 (4)	132
O5—H5⋯O9ⁱ	0.82	1.72	2.535 (4)	172

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Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

We thank the Shanghai Institute of Organic Chemistry for the X-ray data collection and analysis.

supplementary crystallographic information

Comment

The (RS)-(±)-2-carbomethoxy-3-tropinone, I is an important intermediate for preparation of cocaine and its derivatives (Meltzer et al., 1994). It could be resolved by recrystallizing its L- and D-bitartrates (Findlay, 1957). The molecular struture of I is the enol tautomer of the title compound. As shown on Fig. 1, the asymmetric unit of I contains a quaternary ammonium cation and a bitartrate. The 6-membered ring is nearly a chair conformation. The five-membered ring adopts nearly an envelope conformation with N1 atom deviation from C3/C4/C5/C6 plane 0.306 (2)Å. There are intra- and intermolecular hydrogen bonds involving the hydroxyl, carboxyl and quaternary ammonium ions. The system of these H-bond with formation a two-dimensional network presented on Fig. 2. All bond lengths and angles in I are normal.

Experimental

All reagents were of analytical grade and used without further purification. The title compound I was prepared by the general procedure (Findlay, 1957). The single crystals were obtained by evaporation of its methanol solution.