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ISSN: 2056-9890

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

aCollege of Materials Science and Chemical Engineering, Zhejiang University, Hangzhou 310027, People's Republic of China, and bZhejiang Huayi Pharmaceutical Company, Yiwu, Zhejiang 322000, People's Republic of China
*Correspondence e-mail: grzheng@zju.edu.cn

(Received 26 May 2008; accepted 25 July 2008; online 31 July 2008)

(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[Findlay, S. P. (1957). J. Org. Chem. 22, 1385-1394.]); Meltzer et al. (1994[Meltzer, P. C., Liang, A. Y. & Madras, B. K. (1994). J. Med. Chem. 37, 2001-2010.]).

[Scheme 1]

Experimental

Crystal data
  • C10H16NO3+·C4H5O6

  • Mr = 347.32

  • Monoclinic, P 21

  • 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[Sheldrick, G. M. (2002). SADABS. University of Göttingen, Germany.]) Tmin = 0.936, Tmax = 0.961

  • 4145 measured reflections

  • 1522 independent reflections

  • 1460 reflections with I > 2σ(I)

  • Rint = 0.082

Refinement
  • R[F2 > 2σ(F2)] = 0.064

  • wR(F2) = 0.154

  • S = 1.05

  • 1522 reflections

  • 226 parameters

  • 2 restraints

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.38 e Å−3

  • Δρmin = −0.35 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA 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
Symmetry codes: (i) x, y, z+1; (ii) [-x, y-{\script{1\over 2}}, -z+1].

Data collection: SMART (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2001[Bruker (2001). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and publCIF (Westrip, 2008[Westrip, S. P. (2008). publCIF. In preparation.]).

Supporting information


Comment top

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.

Related literature top

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

Experimental top

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.

Refinement top

H atoms were located in a difference Fourier map and refined isotropically with bond restraints N1–H1, other H atoms were positioned geometrically and treated as riding, with C–H and O–H bond lengths constrained to 0.96Å for methyl, 0.97Å for methylene, 0.98Å for methine and 0.82Å for hydroxyl, with Uiso(H) = 1.5Ueq(methyl C and hydroxyl O) and Uiso(H) = 1.2Ueq(methylene and methine C).

The 2813 Friedel pairs were merged.

Computing details top

Data collection: SMART (Bruker, 2001); cell refinement: SAINT (Bruker, 2001); data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2007).

Figures top
[Figure 1] Fig. 1. The molecular structure of I with the atom numbering scheme. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as a small spheres of arbitrary radius.
[Figure 2] Fig. 2. Parts of the two-dimensional network in I. H atoms not involved in hydrogen bonds have been omitted for clarity. Symmetry codes: (A) -x, y-1/2, -z+1; (B) x, y, z+1; (E) -x, y+1/2, -z+1.
(R)-(+)-3-Hydroxy-2-methoxycarbonyl-8-methyl-8- azoniabicyclo[3.2.1]octane L-bitartrate top
Crystal data top
C10H16NO3+·C4H5O6F(000) = 368
Mr = 347.32Dx = 1.464 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 2848 reflections
a = 6.503 (1) Åθ = 5.1–56.6°
b = 15.914 (3) ŵ = 0.12 mm1
c = 7.6626 (12) ÅT = 293 K
β = 96.497 (3)°Prism, colourless
V = 787.9 (2) Å30.50 × 0.49 × 0.37 mm
Z = 2
Data collection top
SMART 1K CCD area-detector
diffractometer
1522 independent reflections
Radiation source: Fine-focus sealed tube1460 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.082
ϕ and ω scansθmax = 25.5°, θmin = 2.6°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)
h = 67
Tmin = 0.936, Tmax = 0.961k = 1919
4145 measured reflectionsl = 98
Refinement top
Refinement on F2Primary atom site location: Direct
Least-squares matrix: FullSecondary atom site location: Difmap
R[F2 > 2σ(F2)] = 0.064Hydrogen site location: Geom
wR(F2) = 0.154H atoms treated by a mixture of independent and constrained refinement
S = 1.05 w = 1/[σ2(Fo2) + (0.1P)2]
where P = (Fo2 + 2Fc2)/3
1522 reflections(Δ/σ)max < 0.001
226 parametersΔρmax = 0.38 e Å3
2 restraintsΔρmin = 0.35 e Å3
Crystal data top
C10H16NO3+·C4H5O6V = 787.9 (2) Å3
Mr = 347.32Z = 2
Monoclinic, P21Mo Kα radiation
a = 6.503 (1) ŵ = 0.12 mm1
b = 15.914 (3) ÅT = 293 K
c = 7.6626 (12) Å0.50 × 0.49 × 0.37 mm
β = 96.497 (3)°
Data collection top
SMART 1K CCD area-detector
diffractometer
1522 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2002)
1460 reflections with I > 2σ(I)
Tmin = 0.936, Tmax = 0.961Rint = 0.082
4145 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0642 restraints
wR(F2) = 0.154H atoms treated by a mixture of independent and constrained refinement
S = 1.05Δρmax = 0.38 e Å3
1522 reflectionsΔρmin = 0.35 e Å3
226 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F^2^ against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F^2^, conventional R-factors R are based on F, with F set to zero for negative F^2^. The threshold expression of F^2^ > σ(F^2^) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F^2^ 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
xyzUiso*/Ueq
O10.4137 (5)0.42707 (19)1.0979 (4)0.0430 (7)
H1A0.33130.44111.01400.064*
O20.2485 (5)0.42415 (18)0.7727 (4)0.0424 (7)
O30.3452 (4)0.31950 (18)0.6043 (3)0.0394 (6)
O40.0156 (5)0.0122 (2)0.7351 (4)0.0490 (7)
O50.2813 (4)0.0965 (2)0.8123 (3)0.0443 (7)
H50.27350.07670.91010.066*
O60.0490 (4)0.0881 (2)0.4144 (4)0.0503 (7)
H6A0.09710.04190.43460.076*
O70.2769 (6)0.03238 (19)0.4196 (4)0.0533 (8)
H70.27130.04790.31710.080*
O80.3679 (5)0.16640 (19)0.2317 (4)0.0470 (7)
O90.2908 (5)0.0395 (2)0.1220 (3)0.0494 (8)
N10.6693 (4)0.20164 (19)1.0231 (4)0.0285 (6)
C10.5207 (5)0.3624 (2)1.0542 (5)0.0302 (7)
C20.6708 (6)0.3287 (2)1.1994 (5)0.0387 (9)
H2A0.59510.30541.29020.046*
H2B0.75620.37431.25090.046*
C30.8082 (5)0.2615 (3)1.1353 (5)0.0356 (8)
H30.88520.23191.23410.043*
C40.9545 (5)0.2942 (3)1.0073 (6)0.0483 (10)
H4A1.08710.26581.02630.058*
H4B0.97710.35411.02300.058*
C50.8474 (6)0.2756 (3)0.8221 (6)0.0437 (9)
H5A0.84670.32490.74750.052*
H5B0.91560.22990.76780.052*
C60.6273 (5)0.2510 (2)0.8544 (5)0.0304 (7)
H60.55960.21650.75870.036*
C70.4975 (5)0.3252 (2)0.8921 (5)0.0298 (7)
C80.3528 (5)0.3622 (2)0.7538 (5)0.0304 (7)
C90.2115 (7)0.3550 (3)0.4589 (6)0.0508 (11)
H9A0.08280.37170.49850.076*
H9B0.18560.31370.36770.076*
H9C0.27740.40310.41390.076*
C100.7663 (6)0.1188 (2)0.9999 (5)0.0390 (8)
H10A0.69430.09080.90030.058*
H10B0.75910.08541.10330.058*
H10C0.90860.12670.98120.058*
C110.1363 (5)0.0638 (2)0.7001 (4)0.0305 (7)
C120.1436 (5)0.0981 (2)0.5152 (4)0.0334 (8)
H120.17520.15820.52400.040*
C130.3152 (5)0.0546 (2)0.4291 (4)0.0327 (8)
H130.44750.06430.50100.039*
C140.3271 (5)0.0916 (3)0.2461 (4)0.0321 (7)
H10.543 (4)0.188 (2)1.068 (5)0.026 (9)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0541 (15)0.0441 (14)0.0301 (14)0.0102 (13)0.0021 (11)0.0035 (13)
O20.0453 (13)0.0446 (14)0.0360 (15)0.0180 (12)0.0015 (11)0.0030 (13)
O30.0432 (13)0.0527 (15)0.0200 (13)0.0097 (12)0.0066 (9)0.0019 (12)
O40.0579 (15)0.0664 (18)0.0237 (13)0.0218 (15)0.0089 (11)0.0036 (14)
O50.0545 (14)0.0633 (16)0.0141 (12)0.0159 (14)0.0000 (10)0.0055 (13)
O60.0430 (13)0.079 (2)0.0269 (14)0.0105 (15)0.0062 (10)0.0089 (15)
O70.089 (2)0.0441 (15)0.0291 (16)0.0119 (16)0.0166 (15)0.0036 (13)
O80.0640 (17)0.0522 (17)0.0267 (15)0.0055 (14)0.0139 (12)0.0041 (13)
O90.0798 (19)0.0564 (16)0.0124 (12)0.0012 (16)0.0067 (12)0.0005 (12)
N10.0293 (12)0.0377 (15)0.0176 (13)0.0008 (11)0.0007 (10)0.0038 (12)
C10.0320 (15)0.0308 (16)0.0272 (19)0.0059 (14)0.0012 (12)0.0005 (14)
C20.0456 (18)0.044 (2)0.0238 (18)0.0020 (17)0.0083 (14)0.0023 (17)
C30.0320 (15)0.0437 (18)0.0277 (18)0.0068 (15)0.0114 (13)0.0067 (16)
C40.0299 (17)0.057 (2)0.058 (3)0.0043 (18)0.0027 (15)0.007 (2)
C50.0405 (18)0.048 (2)0.045 (2)0.0075 (16)0.0155 (15)0.0118 (19)
C60.0323 (15)0.0375 (18)0.0207 (17)0.0010 (14)0.0000 (12)0.0056 (14)
C70.0285 (14)0.0363 (16)0.0235 (17)0.0033 (13)0.0010 (11)0.0032 (14)
C80.0294 (14)0.0359 (17)0.0255 (19)0.0012 (14)0.0018 (13)0.0058 (14)
C90.055 (2)0.072 (3)0.0219 (19)0.016 (2)0.0107 (16)0.007 (2)
C100.0442 (18)0.0422 (19)0.0292 (19)0.0088 (16)0.0010 (14)0.0049 (16)
C110.0374 (15)0.0406 (17)0.0138 (16)0.0002 (14)0.0043 (11)0.0035 (15)
C120.0439 (17)0.0420 (18)0.0140 (16)0.0032 (16)0.0026 (13)0.0020 (15)
C130.0422 (17)0.0451 (19)0.0103 (16)0.0031 (15)0.0000 (12)0.0035 (14)
C140.0382 (16)0.046 (2)0.0118 (15)0.0002 (15)0.0041 (11)0.0018 (15)
Geometric parameters (Å, º) top
O1—C11.307 (5)C3—C41.533 (6)
O1—H1A0.8200C3—H30.9800
O2—C81.215 (4)C4—C51.537 (7)
O3—C81.328 (5)C4—H4A0.9700
O3—C91.448 (4)C4—H4B0.9700
O4—C111.188 (5)C5—C61.531 (5)
O5—C111.309 (4)C5—H5A0.9700
O5—H50.8200C5—H5B0.9700
O6—C121.404 (4)C6—C71.498 (5)
O6—H6A0.8200C6—H60.9800
O7—C131.407 (5)C7—C81.459 (5)
O7—H70.8200C9—H9A0.9600
O8—C141.228 (5)C9—H9B0.9600
O9—C141.262 (5)C9—H9C0.9600
N1—C101.481 (5)C10—H10A0.9600
N1—C61.511 (4)C10—H10B0.9600
N1—C31.511 (4)C10—H10C0.9600
N1—H10.954 (19)C11—C121.524 (4)
C1—C71.369 (5)C12—C131.525 (5)
C1—C21.495 (5)C12—H120.9800
C2—C31.511 (6)C13—C141.531 (4)
C2—H2A0.9700C13—H130.9800
C2—H2B0.9700
C1—O1—H1A109.5N1—C6—C5100.9 (3)
C8—O3—C9115.2 (3)C7—C6—H6111.8
C11—O5—H5109.5N1—C6—H6111.8
C12—O6—H6A109.5C5—C6—H6111.8
C13—O7—H7109.5C1—C7—C8118.7 (3)
C10—N1—C6113.5 (3)C1—C7—C6120.6 (3)
C10—N1—C3113.2 (3)C8—C7—C6120.6 (3)
C6—N1—C3101.4 (3)O2—C8—O3123.4 (3)
C10—N1—H1103 (2)O2—C8—C7124.4 (3)
C6—N1—H1111 (2)O3—C8—C7112.2 (3)
C3—N1—H1115 (2)O3—C9—H9A109.5
O1—C1—C7124.5 (3)O3—C9—H9B109.5
O1—C1—C2114.5 (3)H9A—C9—H9B109.5
C7—C1—C2121.0 (3)O3—C9—H9C109.5
C1—C2—C3111.9 (3)H9A—C9—H9C109.5
C1—C2—H2A109.2H9B—C9—H9C109.5
C3—C2—H2A109.2N1—C10—H10A109.5
C1—C2—H2B109.2N1—C10—H10B109.5
C3—C2—H2B109.2H10A—C10—H10B109.5
H2A—C2—H2B107.9N1—C10—H10C109.5
C2—C3—N1107.1 (3)H10A—C10—H10C109.5
C2—C3—C4113.6 (3)H10B—C10—H10C109.5
N1—C3—C4103.0 (3)O4—C11—O5124.9 (3)
C2—C3—H3111.0O4—C11—C12123.2 (3)
N1—C3—H3111.0O5—C11—C12111.8 (3)
C4—C3—H3111.0O6—C12—C11110.6 (3)
C3—C4—C5106.0 (3)O6—C12—C13111.2 (3)
C3—C4—H4A110.5C11—C12—C13110.0 (3)
C5—C4—H4A110.5O6—C12—H12108.3
C3—C4—H4B110.5C11—C12—H12108.3
C5—C4—H4B110.5C13—C12—H12108.3
H4A—C4—H4B108.7O7—C13—C12109.5 (3)
C6—C5—C4103.5 (3)O7—C13—C14111.0 (3)
C6—C5—H5A111.1C12—C13—C14109.7 (3)
C4—C5—H5A111.1O7—C13—H13108.9
C6—C5—H5B111.1C12—C13—H13108.9
C4—C5—H5B111.1C14—C13—H13108.9
H5A—C5—H5B109.0O8—C14—O9126.3 (3)
C7—C6—N1107.2 (3)O8—C14—C13119.2 (3)
C7—C6—C5112.8 (3)O9—C14—C13114.4 (3)
O1—C1—C2—C3172.8 (3)C5—C6—C7—C177.6 (4)
C7—C1—C2—C39.1 (5)N1—C6—C7—C8151.1 (3)
C1—C2—C3—N147.1 (4)C5—C6—C7—C898.7 (4)
C1—C2—C3—C465.9 (4)C9—O3—C8—O23.7 (5)
C10—N1—C3—C2160.7 (3)C9—O3—C8—C7177.3 (3)
C6—N1—C3—C277.4 (3)C1—C7—C8—O20.7 (5)
C10—N1—C3—C479.3 (3)C6—C7—C8—O2177.0 (3)
C6—N1—C3—C442.6 (3)C1—C7—C8—O3179.7 (3)
C2—C3—C4—C596.8 (4)C6—C7—C8—O33.9 (4)
N1—C3—C4—C518.7 (4)O4—C11—C12—O623.5 (5)
C3—C4—C5—C611.9 (4)O5—C11—C12—O6158.1 (3)
C10—N1—C6—C7170.3 (3)O4—C11—C12—C1399.7 (4)
C3—N1—C6—C768.0 (3)O5—C11—C12—C1378.7 (4)
C10—N1—C6—C571.4 (4)O6—C12—C13—O762.8 (4)
C3—N1—C6—C550.2 (3)C11—C12—C13—O760.0 (4)
C4—C5—C6—C776.1 (4)O6—C12—C13—C1459.3 (4)
C4—C5—C6—N137.9 (4)C11—C12—C13—C14177.9 (3)
O1—C1—C7—C83.8 (5)O7—C13—C14—O8177.1 (3)
C2—C1—C7—C8178.4 (3)C12—C13—C14—O861.7 (4)
O1—C1—C7—C6179.8 (3)O7—C13—C14—O93.4 (4)
C2—C1—C7—C62.0 (5)C12—C13—C14—O9117.8 (3)
N1—C6—C7—C132.6 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O20.821.892.600 (4)145
O7—H7···O90.822.062.562 (4)120
N1—H1···O8i0.95 (2)1.82 (2)2.724 (4)158 (4)
O6—H6A···O2ii0.822.583.182 (4)132
O5—H5···O9i0.821.722.535 (4)172
Symmetry codes: (i) x, y, z+1; (ii) x, y1/2, z+1.

Experimental details

Crystal data
Chemical formulaC10H16NO3+·C4H5O6
Mr347.32
Crystal system, space groupMonoclinic, P21
Temperature (K)293
a, b, c (Å)6.503 (1), 15.914 (3), 7.6626 (12)
β (°) 96.497 (3)
V3)787.9 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.12
Crystal size (mm)0.50 × 0.49 × 0.37
Data collection
DiffractometerSMART 1K CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2002)
Tmin, Tmax0.936, 0.961
No. of measured, independent and
observed [I > 2σ(I)] reflections
4145, 1522, 1460
Rint0.082
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.154, 1.05
No. of reflections1522
No. of parameters226
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.38, 0.35

Computer programs: SMART (Bruker, 2001), SAINT (Bruker, 2001), SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2007).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O1—H1A···O20.821.892.600 (4)145.0
O7—H7···O90.822.062.562 (4)119.6
N1—H1···O8i0.954 (19)1.82 (2)2.724 (4)158 (4)
O6—H6A···O2ii0.822.583.182 (4)131.5
O5—H5···O9i0.821.722.535 (4)172.3
Symmetry codes: (i) x, y, z+1; (ii) x, y1/2, z+1.
 

Acknowledgements

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

References

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