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Acta Crystallogr Sect E Struct Rep Online. 2009 November 1; 65(Pt 11): o2748.
Published online 2009 October 17. doi:  10.1107/S1600536809041385
PMCID: PMC2971213

2-Hydr­oxy-6,6-dimethyl­bicyclo­[3.1.1]heptane-2-carboxylic acid

Abstract

The title compound, C10H16O3, with a bicyclo­[3.1.1]heptane unit, was obtained by oxidation of β-pinene. The asymmetric unit contains two independent mol­ecules with similar geometry: the six-membered rings in both mol­ecules adopt envelope conformations. In the crystal, the independent mol­ecules exist as O—H(...)O hydrogen-bonded dimers. The dimers are linked into helical chains along the b axis by O—H(...)O hydrogen bonds.

Related literature

For the preparation of nopinone and nopinic acid, see: Winstein & Holness (1955 [triangle]); Ma et al. (2007 [triangle]). For the crystal structure of sodium nopinate [sodium (1R,2S,5S)-2-hydr­oxy-6,6-dimethyl­bicyclo­[3.1.1]heptane-2-carboxyl­ate penta­hydrate], see: Ma et al. (2008 [triangle]).

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Object name is e-65-o2748-scheme1.jpg

Experimental

Crystal data

  • C10H16O3
  • M r = 184.23
  • Monoclinic, An external file that holds a picture, illustration, etc.
Object name is e-65-o2748-efi1.jpg
  • a = 26.796 (5) Å
  • b = 6.6560 (13) Å
  • c = 12.250 (3) Å
  • β = 112.23 (3)°
  • V = 2022.5 (9) Å3
  • Z = 8
  • Mo Kα radiation
  • μ = 0.09 mm−1
  • T = 293 K
  • 0.30 × 0.20 × 0.20 mm

Data collection

  • Enraf–Nonius CAD-4 diffractometer
  • Absorption correction: ψ scan (XCAD4; Harms & Wocadlo, 1995 [triangle]) T min = 0.974, T max = 0.983
  • 2047 measured reflections
  • 2002 independent reflections
  • 1565 reflections with I > 2σ(I)
  • R int = 0.018
  • 3 standard reflections every 200 reflections intensity decay: 1%

Refinement

  • R[F 2 > 2σ(F 2)] = 0.056
  • wR(F 2) = 0.153
  • S = 1.00
  • 2002 reflections
  • 242 parameters
  • 3 restraints
  • H atoms treated by a mixture of independent and constrained refinement
  • Δρmax = 0.21 e Å−3
  • Δρmin = −0.23 e Å−3

Data collection: CAD-4 Software (Enraf–Nonius, 1989 [triangle]); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 [triangle]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: SHELXTL (Sheldrick, 2008 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809041385/ci2928sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809041385/ci2928Isup2.hkl

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

supplementary crystallographic information

Comment

Terpenes are convenient chiral precursors due to their availability and low cost, and among them β-pinene is an important material. Many valuable chemicals were prepared from β-pinene. For instance, nopinone (Winstein & Holness, 1955) and nopinic acid were prepared by oxidation of β-pinene. Although the title compound has been prepared (Ma et al., 2007) and the crystal structure of sodium nopinate has been reported (Ma et al., 2008), the crystal structure of nopinic acid has not been reported. In this paper, we report the crystal structure of the title compound.

The asymmetric unit contains two crystallographically independent molecules (Fig. 1) with similar geometry. The six-membered rings in both the molecules adopt envelope conformations. The independent molecules are linked through a pair of O–H···O hydrogen bonds (Table 1) forming a dimer. The dimers are linked into helical chains along the b axis (Fig. 2) by O—H···O hydrogen bonds.

Experimental

Potassium permanganate (12.0 g) and NaOH (1.5 g) were dissolved in the mixture of water (100 ml) and t-butylalcohol (50 ml). While stirring vigorously, pure (-)-beta-pinene (5.2 g) was added. The reaction was maintained at the temperature of 288–298 K for 0.5 h. The mixture was heated to 353 K, then filtered and the precipitate was washed with hot water. After standing for 12 h at 273 K, sodium nopinate was filtered. The crude sodium nopinate was acidified with dilute hydrochloric acid and extracted with dichloromethane, then the product, crude nopinic acid was obtained. The crude nopinic acid was recrystallized from toluene. Single crystals of the title compound suitable for X-ray diffraction were obtained by slow evaporation of a ethanol-toluene solution.

Refinement

H atoms of hydroxyl groups were located in a difference map and their parameters were refined with a O-H distance restraint of 0.82 (1) Å. The remaining H atoms were positioned geometrically [O-H = 0.82 Å and C-H = 0.96–0.98 Å] and included in the refinement in the riding motion approximation, with Uiso(H) = 1.2 or 1.5Ueq of the carrier atom. In the absence of significant anomalous scattering, Friedel pairs were merged prior to the final refinement.

Figures

Fig. 1.
The asymmetric unit of the title compound. Displacement ellipsoids are drawn at the 30% probability level. Hydrogen bonds are shown as dashed lines.
Fig. 2.
Crystal packing of the title compound, viewed along the a axis. Hydrogen bonds are shown as dashed lines.

Crystal data

C10H16O3F(000) = 800
Mr = 184.23Dx = 1.210 Mg m3
Monoclinic, C2Mo Kα radiation, λ = 0.71073 Å
Hall symbol: C 2yCell parameters from 25 reflections
a = 26.796 (5) Åθ = 10–13°
b = 6.6560 (13) ŵ = 0.09 mm1
c = 12.250 (3) ÅT = 293 K
β = 112.23 (3)°Block, colourless
V = 2022.5 (9) Å30.30 × 0.20 × 0.20 mm
Z = 8

Data collection

Enraf–Nonius CAD-4 diffractometer1565 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.018
graphiteθmax = 25.3°, θmin = 1.6°
ω/2θ scansh = 0→32
Absorption correction: ψ scan (XCAD4; Harms & Wocadlo, 1995)k = 0→7
Tmin = 0.974, Tmax = 0.983l = −14→13
2047 measured reflections3 standard reflections every 200 reflections
2002 independent reflections intensity decay: 1%

Refinement

Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.056H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.153w = 1/[σ2(Fo2) + (0.1P)2 + 0.3P] where P = (Fo2 + 2Fc2)/3
S = 1.00(Δ/σ)max = 0.001
2002 reflectionsΔρmax = 0.21 e Å3
242 parametersΔρmin = −0.23 e Å3
3 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.044 (4)

Special details

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)

xyzUiso*/Ueq
O10.03238 (12)0.4845 (8)0.2047 (3)0.0997 (14)
H1A0.021 (3)0.504 (15)0.134 (2)0.150*
C10.2225 (3)0.6237 (14)0.2710 (5)0.116 (2)
H1B0.21580.75190.29860.174*
H1C0.21710.63360.18910.174*
H1D0.25900.58360.31560.174*
O20.07227 (15)0.3644 (5)0.0307 (3)0.0842 (10)
H2D0.06770.2896−0.02550.126*
C20.1946 (2)0.2647 (10)0.2414 (5)0.0941 (19)
H2A0.19460.28140.16350.141*
H2B0.16720.17010.23910.141*
H2C0.22920.21570.29310.141*
O30.06567 (14)0.0776 (5)0.1168 (3)0.0724 (9)
C30.18336 (16)0.4660 (9)0.2865 (4)0.0672 (12)
C40.18223 (17)0.4726 (8)0.4114 (4)0.0681 (12)
H4A0.21640.50830.47470.082*
C50.14121 (19)0.6413 (8)0.3696 (4)0.0732 (13)
H5A0.15690.77460.37810.088*
H5B0.11300.63560.40090.088*
C60.12546 (16)0.5514 (7)0.2461 (3)0.0601 (10)
H6A0.11620.64980.18200.072*
C70.08375 (14)0.3881 (7)0.2299 (3)0.0571 (10)
C80.0964 (2)0.2662 (9)0.3430 (4)0.0835 (16)
H8A0.09010.12520.32230.100*
H8B0.07140.30560.37940.100*
C90.1543 (2)0.2906 (9)0.4343 (4)0.0841 (16)
H9A0.15330.30130.51240.101*
H9B0.17500.17160.43300.101*
C100.07381 (16)0.2592 (7)0.1207 (4)0.0542 (10)
O4−0.00459 (10)−0.2034 (5)−0.3282 (2)0.0640 (8)
H4C−0.010 (2)−0.270 (8)−0.276 (4)0.096*
O50.05228 (13)−0.1491 (5)−0.0754 (2)0.0677 (8)
H5C0.0566−0.0769−0.01830.102*
O60.05719 (14)0.1444 (5)−0.1566 (3)0.0714 (9)
C110.1765 (2)−0.5132 (10)−0.1362 (6)0.0972 (18)
H11A0.1808−0.5215−0.05490.146*
H11B0.2114−0.5142−0.14160.146*
H11C0.1559−0.6262−0.17850.146*
C120.17137 (18)−0.1448 (10)−0.1071 (4)0.0769 (14)
H12A0.1733−0.1796−0.02950.115*
H12B0.1495−0.0269−0.13390.115*
H12C0.2070−0.1186−0.10480.115*
C130.14673 (15)−0.3165 (7)−0.1904 (4)0.0591 (11)
C140.08439 (14)−0.3538 (6)−0.2409 (3)0.0480 (9)
H14A0.0720−0.4534−0.19780.058*
C150.08937 (19)−0.4313 (7)−0.3542 (4)0.0660 (11)
H15A0.0597−0.3933−0.42600.079*
H15B0.0973−0.5737−0.35320.079*
C160.13896 (18)−0.2949 (7)−0.3219 (4)0.0650 (12)
H16A0.1685−0.3484−0.34200.078*
C170.1211 (2)−0.0838 (8)−0.3660 (4)0.0675 (13)
H17A0.1174−0.0727−0.44760.081*
H17B0.14830.0115−0.32000.081*
C180.06712 (17)−0.0321 (7)−0.3564 (3)0.0599 (11)
H18A0.06810.1080−0.33390.072*
H18B0.0388−0.0464−0.43390.072*
C190.05197 (13)−0.1576 (6)−0.2696 (3)0.0461 (9)
C200.05493 (15)−0.0405 (6)−0.1616 (3)0.0509 (9)

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
O10.0457 (16)0.123 (3)0.119 (3)0.014 (2)0.0179 (17)−0.057 (3)
C10.100 (4)0.146 (7)0.110 (4)−0.050 (5)0.050 (3)−0.019 (5)
O20.131 (3)0.0553 (19)0.0582 (17)−0.002 (2)0.0263 (16)−0.0013 (17)
C20.056 (3)0.120 (5)0.104 (4)0.024 (3)0.028 (3)−0.017 (4)
O30.099 (2)0.0558 (19)0.0706 (19)−0.0094 (18)0.0413 (17)−0.0104 (16)
C30.046 (2)0.084 (3)0.071 (3)0.000 (2)0.0214 (18)−0.005 (3)
C40.052 (2)0.080 (3)0.058 (2)−0.005 (2)0.0052 (17)−0.004 (2)
C50.071 (3)0.066 (3)0.076 (3)−0.005 (3)0.020 (2)−0.023 (3)
C60.063 (2)0.049 (2)0.057 (2)0.010 (2)0.0102 (17)0.001 (2)
C70.042 (2)0.065 (3)0.064 (2)0.008 (2)0.0191 (16)−0.013 (2)
C80.101 (4)0.093 (4)0.067 (3)−0.035 (3)0.044 (3)−0.019 (3)
C90.108 (4)0.085 (4)0.051 (2)−0.004 (3)0.021 (2)0.007 (3)
C100.051 (2)0.055 (3)0.055 (2)0.0081 (19)0.0183 (18)−0.0031 (19)
O40.0449 (14)0.072 (2)0.0648 (16)−0.0111 (15)0.0095 (12)0.0054 (16)
O50.103 (2)0.0507 (17)0.0607 (16)−0.0033 (17)0.0441 (15)0.0021 (15)
O60.103 (2)0.0429 (18)0.0730 (19)−0.0012 (17)0.0385 (17)−0.0001 (15)
C110.076 (3)0.086 (4)0.126 (5)0.022 (3)0.034 (3)0.021 (4)
C120.053 (3)0.090 (4)0.072 (3)−0.004 (3)0.006 (2)−0.001 (3)
C130.045 (2)0.059 (3)0.071 (2)0.003 (2)0.0190 (17)0.000 (2)
C140.051 (2)0.0404 (19)0.055 (2)−0.0065 (18)0.0232 (16)0.0045 (18)
C150.083 (3)0.049 (2)0.073 (3)−0.011 (2)0.037 (2)−0.014 (2)
C160.070 (3)0.062 (3)0.078 (3)−0.006 (2)0.046 (2)−0.007 (2)
C170.085 (3)0.065 (3)0.062 (2)−0.022 (2)0.038 (2)−0.003 (2)
C180.069 (3)0.054 (2)0.054 (2)−0.008 (2)0.0204 (18)0.007 (2)
C190.0426 (18)0.047 (2)0.0460 (18)−0.0062 (17)0.0140 (14)0.0038 (17)
C200.049 (2)0.046 (3)0.059 (2)0.0046 (18)0.0217 (17)0.0058 (19)

Geometric parameters (Å, °)

O1—C71.442 (5)O4—C191.443 (4)
O1—H1A0.82 (2)O4—H4C0.84 (5)
C1—C31.546 (8)O5—C201.303 (5)
C1—H1B0.96O5—H5C0.82
C1—H1C0.96O6—C201.232 (5)
C1—H1D0.96C11—C131.547 (8)
O2—C101.294 (5)C11—H11A0.96
O2—H2D0.82C11—H11B0.96
C2—C31.523 (8)C11—H11C0.96
C2—H2A0.96C12—C131.508 (7)
C2—H2B0.96C12—H12A0.96
C2—H2C0.96C12—H12B0.96
O3—C101.226 (6)C12—H12C0.96
C3—C41.542 (6)C13—C161.550 (6)
C3—C61.547 (6)C13—C141.566 (5)
C4—C91.505 (8)C14—C151.533 (5)
C4—C51.518 (7)C14—C191.534 (5)
C4—H4A0.98C14—H14A0.98
C5—C61.530 (6)C15—C161.533 (6)
C5—H5A0.97C15—H15A0.97
C5—H5B0.97C15—H15B0.97
C6—C71.517 (6)C16—C171.517 (7)
C6—H6A0.98C16—H16A0.98
C7—C101.526 (6)C17—C181.533 (6)
C7—C81.529 (7)C17—H17A0.97
C8—C91.540 (7)C17—H17B0.97
C8—H8A0.97C18—C191.523 (5)
C8—H8B0.97C18—H18A0.97
C9—H9A0.97C18—H18B0.97
C9—H9B0.97C19—C201.512 (5)
C7—O1—H1A103 (6)C19—O4—H4C100 (4)
C3—C1—H1B109.5C20—O5—H5C109.5
C3—C1—H1C109.5C13—C11—H11A109.5
H1B—C1—H1C109.5C13—C11—H11B109.5
C3—C1—H1D109.5H11A—C11—H11B109.5
H1B—C1—H1D109.5C13—C11—H11C109.5
H1C—C1—H1D109.5H11A—C11—H11C109.5
C10—O2—H2D109.5H11B—C11—H11C109.5
C3—C2—H2A109.5C13—C12—H12A109.5
C3—C2—H2B109.5C13—C12—H12B109.5
H2A—C2—H2B109.5H12A—C12—H12B109.5
C3—C2—H2C109.5C13—C12—H12C109.5
H2A—C2—H2C109.5H12A—C12—H12C109.5
H2B—C2—H2C109.5H12B—C12—H12C109.5
C2—C3—C4117.8 (5)C12—C13—C11109.2 (4)
C2—C3—C1108.4 (4)C12—C13—C16119.0 (4)
C4—C3—C1111.8 (4)C11—C13—C16111.6 (4)
C2—C3—C6121.3 (4)C12—C13—C14121.0 (4)
C4—C3—C685.0 (3)C11—C13—C14109.6 (4)
C1—C3—C6110.9 (5)C16—C13—C1484.3 (3)
C9—C4—C5108.1 (4)C15—C14—C19108.3 (3)
C9—C4—C3111.1 (4)C15—C14—C1388.0 (3)
C5—C4—C388.3 (3)C19—C14—C13112.5 (3)
C9—C4—H4A115.4C15—C14—H14A115.0
C5—C4—H4A115.4C19—C14—H14A115.0
C3—C4—H4A115.4C13—C14—H14A115.0
C4—C5—C686.4 (3)C14—C15—C1686.0 (3)
C4—C5—H5A114.2C14—C15—H15A114.3
C6—C5—H5A114.2C16—C15—H15A114.3
C4—C5—H5B114.2C14—C15—H15B114.3
C6—C5—H5B114.2C16—C15—H15B114.3
H5A—C5—H5B111.4H15A—C15—H15B111.5
C7—C6—C5108.9 (4)C17—C16—C15109.3 (4)
C7—C6—C3112.2 (4)C17—C16—C13110.8 (4)
C5—C6—C387.7 (3)C15—C16—C1388.6 (3)
C7—C6—H6A115.0C17—C16—H16A115.1
C5—C6—H6A115.0C15—C16—H16A115.1
C3—C6—H6A115.0C13—C16—H16A115.1
O1—C7—C6107.8 (4)C16—C17—C18111.1 (4)
O1—C7—C10103.1 (3)C16—C17—H17A109.4
C6—C7—C10113.1 (3)C18—C17—H17A109.4
O1—C7—C8107.2 (4)C16—C17—H17B109.4
C6—C7—C8111.2 (3)C18—C17—H17B109.4
C10—C7—C8113.7 (4)H17A—C17—H17B108.0
C7—C8—C9114.7 (4)C19—C18—C17116.0 (4)
C7—C8—H8A108.6C19—C18—H18A108.3
C9—C8—H8A108.6C17—C18—H18A108.3
C7—C8—H8B108.6C19—C18—H18B108.3
C9—C8—H8B108.6C17—C18—H18B108.3
H8A—C8—H8B107.6H18A—C18—H18B107.4
C4—C9—C8112.7 (4)O4—C19—C20104.0 (3)
C4—C9—H9A109.1O4—C19—C18106.0 (3)
C8—C9—H9A109.1C20—C19—C18112.9 (3)
C4—C9—H9B109.1O4—C19—C14109.3 (3)
C8—C9—H9B109.1C20—C19—C14113.6 (3)
H9A—C9—H9B107.8C18—C19—C14110.5 (3)
O3—C10—O2123.6 (4)O6—C20—O5122.0 (4)
O3—C10—C7123.9 (4)O6—C20—C19122.9 (4)
O2—C10—C7112.4 (4)O5—C20—C19115.0 (3)
C2—C3—C4—C9−40.5 (5)C12—C13—C14—C15147.2 (4)
C1—C3—C4—C9−167.1 (5)C11—C13—C14—C15−84.4 (4)
C6—C3—C4—C982.4 (4)C16—C13—C14—C1526.6 (3)
C2—C3—C4—C5−149.2 (4)C12—C13—C14—C1938.2 (5)
C1—C3—C4—C584.2 (5)C11—C13—C14—C19166.6 (4)
C6—C3—C4—C5−26.3 (3)C16—C13—C14—C19−82.4 (3)
C9—C4—C5—C6−85.0 (4)C19—C14—C15—C1686.2 (3)
C3—C4—C5—C626.6 (3)C13—C14—C15—C16−26.9 (3)
C4—C5—C6—C786.2 (4)C14—C15—C16—C17−84.5 (4)
C4—C5—C6—C3−26.5 (4)C14—C15—C16—C1327.2 (3)
C2—C3—C6—C736.3 (5)C12—C13—C16—C17−39.0 (5)
C4—C3—C6—C7−83.3 (4)C11—C13—C16—C17−167.6 (4)
C1—C3—C6—C7165.2 (4)C14—C13—C16—C1783.5 (4)
C2—C3—C6—C5145.8 (5)C12—C13—C16—C15−149.1 (4)
C4—C3—C6—C526.1 (4)C11—C13—C16—C1582.2 (4)
C1—C3—C6—C5−85.4 (4)C14—C13—C16—C15−26.6 (3)
C5—C6—C7—O178.6 (4)C15—C16—C17—C1835.4 (5)
C3—C6—C7—O1174.0 (3)C13—C16—C17—C18−60.7 (4)
C5—C6—C7—C10−168.0 (4)C16—C17—C18—C1920.9 (5)
C3—C6—C7—C10−72.7 (4)C17—C18—C19—O4−137.5 (4)
C5—C6—C7—C8−38.6 (5)C17—C18—C19—C20109.3 (4)
C3—C6—C7—C856.7 (5)C17—C18—C19—C14−19.2 (5)
O1—C7—C8—C9−134.0 (5)C15—C14—C19—O477.7 (3)
C6—C7—C8—C9−16.4 (6)C13—C14—C19—O4173.3 (3)
C10—C7—C8—C9112.7 (5)C15—C14—C19—C20−166.6 (3)
C5—C4—C9—C838.3 (6)C13—C14—C19—C20−71.0 (4)
C3—C4—C9—C8−57.0 (6)C15—C14—C19—C18−38.6 (4)
C7—C8—C9—C416.9 (7)C13—C14—C19—C1857.0 (4)
O1—C7—C10—O3−101.6 (5)O4—C19—C20—O6−99.0 (5)
C6—C7—C10—O3142.3 (5)C18—C19—C20—O615.5 (5)
C8—C7—C10—O314.1 (6)C14—C19—C20—O6142.2 (4)
O1—C7—C10—O275.2 (5)O4—C19—C20—O577.9 (4)
C6—C7—C10—O2−40.9 (5)C18—C19—C20—O5−167.7 (3)
C8—C7—C10—O2−169.1 (4)C14—C19—C20—O5−40.9 (4)

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
O1—H1A···O20.81 (3)2.38 (8)2.837 (5)116 (7)
O2—H2D···O60.821.802.621 (5)175
O4—H4C···O1i0.84 (5)2.05 (5)2.830 (5)156 (5)
O5—H5C···O30.821.882.704 (4)177

Symmetry codes: (i) −x, y−1, −z.

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: CI2928).

References

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