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The structure of the title compound, C10H18O3, can be described in the space group Cc with two independent mol­ecules in the asymmetric unit almost related by a twofold axis due to the different orientations of the H atoms of the hydroxyl groups. However, in the space group C2/c this pseudo-twofold axis is a crystallographic one and these H atoms appear to be disordered. The same situation (Cambridge Structural Database, CSD) has been observed in the structure of the carbobicyclic derivative (CSD refcode SEWXAT), described in the space group Pc with two independent mol­ecules, while in the thio­bicyclic analogue (SEWXEX), the H atoms are disordered in the space group P21/c. In these three compounds, the hydroxyl groups are in equatorial positions and anti with respect to the ether atom bridge. The supra­molecular structure of the title compound consists of layers where the hydroxyl groups are involved as donor and acceptor of hydrogen bonds [graph-set motif R44(8)]. This layered structure shows a close resemblance to those of the carbo- and thio­bicyclic analogues but is dissimilar to that of the exo diastereoisomer derivative, which has OH groups in a syn disposition with respect to the ether bridge (WASWAO).

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807032163/ym2059sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536807032163/ym2059Isup2.hkl
Contains datablock I

CCDC reference: 657796

Key indicators

  • Single-crystal X-ray study
  • T = 170 K
  • Mean [sigma](C-C) = 0.002 Å
  • R factor = 0.045
  • wR factor = 0.122
  • Data-to-parameter ratio = 18.3

checkCIF/PLATON results

No syntax errors found



Alert level C PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low ....... 0.98
Alert level G PLAT793_ALERT_1_G Check the Absolute Configuration of C1 = ... S PLAT793_ALERT_1_G Check the Absolute Configuration of C2 = ... S PLAT793_ALERT_1_G Check the Absolute Configuration of C5 = ... S PLAT793_ALERT_1_G Check the Absolute Configuration of C6 = ... S
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 1 ALERT level C = Check and explain 4 ALERT level G = General alerts; check 4 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 0 ALERT type 2 Indicator that the structure model may be wrong or deficient 1 ALERT type 3 Indicator that the structure quality may be low 0 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check

Comment top

In a project related with the synthesis of a universal template for resolution of racemic mixtures of secondary alcohols, the intermediate title compound was synthesized (Carrasco, 2001). On the other hand, the analogous syn-diols derivatives studied so far have proved to have inclusion behaviour (Kim et al., 2002).

The two independent molecules of (I) in the Cc space group differ from each other only in the orientation of the H atoms of the hydroxyl groups. The molecules are almost related by a twofold axis which is a crystallographic one in the C2/c space group and, therefore, the H atoms are split into two positions (Figure 1). The same situation has been observed (Cambridge Crystallographic Database, Allen, 2002) in the structure of the endo-2,endo-6-dihydroxy-2,6-dimethylbicyclo(3.3.1)nonane compound described in the Pc group (SEWXAT refcode: Hawkins et al., 1990) with a CH2 group instead of the ether bridge while in the thio-bicycle derivative (SEWXEX refcode, P21/c space group: Hawkins et al., 1990) the H of the hydroxyl groups appear to be disordered.

The six-membered rings are in a slightly distorted chair conformation with the hydroxyl groups in equatorial position, anti with respect to the ether atom O1 (Table 1). These OH groups are involved in the formation of the R44(8) hydrogen bonding motif (Bernstein et al., 1995) acting as both donor and acceptor of hydrogen bonds that results into sheets (Table 2, Figure 2 and 3). Weak C—H···Oether contacts link the layers into a three-dimensional network (2.65, 3.613 (1)Å and 162° for the H···A, D···A distances and DH···A angle). This layered structure is similar to that of carbo-bicycle and thio-biclycle analogues (SEWXAT and SEWXEX) but dissimilar to that of the exo diastereoisomer derivative (OH groups in syn disposition with respect to the ether bridge (WASWAO, Pich et al., 1993). These results are in agreement with the rules proposed by Kim et al., (2002) to be fulfilled by the molecular structure of these derivatives to form supramolecular tubulant hydrogen-bonding networks.

Related literature top

For the related structures [Cambridge Structural Database (CSD), Version 5.28; Allen, 2002] of the endo-2,endo-6-dihydroxy-2,6-dimethylbicyclo(3.3.1)nonane (CSD refcode SEWXAT) and endo-2,endo-6-dihydroxy-2,6-thiobicyclo(3.3.1)nonane (CSD refcode SEWXEX) analogues, see: Hawkins et al. (1990). For the exo diastereoisomer (CSD refcode WASWAO) of the title compound, see: Pich et al. (1993). For syn-diol derivatives with inclusion behaviour, see: Kim et al. (2002).

For related literature, see: Bernstein et al. (1995); Carrasco (2001).

Experimental top

Compound (I) was synthesized (Carrasco, 2001) within a project related with the synthesis of a universal template for resolution of racemic mixtures of secondary alcohols and was crystallized from a mixture of acetone/n-hexane at 50%. No structural phase transition was detected when cooling the sample from room temperature to 170 K.

Refinement top

Refinements were performed in the Cc and C2/c space groups. In the C2/c group, the H atom of the hydroxyl groups were split into two positions while in the Cc space group refinements were carried out with two independent molecules without disorder. The lack of suitable anomalous scatters did not allow us to reliably determine the absolute structure according to the Flack parameters = 0.3 (14) and, therefore, the Friedel pairs were merged. All hydrogen atoms were located on difference Fourier maps and they were included in the refinement in the riding-model approximation with C—H = 0.98 (CH3), 0.99 (CH2), 1.00 (CH) and O—H = 0.84 Å with Uiso(H) = 1.2Ueq(C,O).

Structure description top

In a project related with the synthesis of a universal template for resolution of racemic mixtures of secondary alcohols, the intermediate title compound was synthesized (Carrasco, 2001). On the other hand, the analogous syn-diols derivatives studied so far have proved to have inclusion behaviour (Kim et al., 2002).

The two independent molecules of (I) in the Cc space group differ from each other only in the orientation of the H atoms of the hydroxyl groups. The molecules are almost related by a twofold axis which is a crystallographic one in the C2/c space group and, therefore, the H atoms are split into two positions (Figure 1). The same situation has been observed (Cambridge Crystallographic Database, Allen, 2002) in the structure of the endo-2,endo-6-dihydroxy-2,6-dimethylbicyclo(3.3.1)nonane compound described in the Pc group (SEWXAT refcode: Hawkins et al., 1990) with a CH2 group instead of the ether bridge while in the thio-bicycle derivative (SEWXEX refcode, P21/c space group: Hawkins et al., 1990) the H of the hydroxyl groups appear to be disordered.

The six-membered rings are in a slightly distorted chair conformation with the hydroxyl groups in equatorial position, anti with respect to the ether atom O1 (Table 1). These OH groups are involved in the formation of the R44(8) hydrogen bonding motif (Bernstein et al., 1995) acting as both donor and acceptor of hydrogen bonds that results into sheets (Table 2, Figure 2 and 3). Weak C—H···Oether contacts link the layers into a three-dimensional network (2.65, 3.613 (1)Å and 162° for the H···A, D···A distances and DH···A angle). This layered structure is similar to that of carbo-bicycle and thio-biclycle analogues (SEWXAT and SEWXEX) but dissimilar to that of the exo diastereoisomer derivative (OH groups in syn disposition with respect to the ether bridge (WASWAO, Pich et al., 1993). These results are in agreement with the rules proposed by Kim et al., (2002) to be fulfilled by the molecular structure of these derivatives to form supramolecular tubulant hydrogen-bonding networks.

For the related structures [Cambridge Structural Database (CSD), Version 5.28; Allen, 2002] of the endo-2,endo-6-dihydroxy-2,6-dimethylbicyclo(3.3.1)nonane (CSD refcode SEWXAT) and endo-2,endo-6-dihydroxy-2,6-thiobicyclo(3.3.1)nonane (CSD refcode SEWXEX) analogues, see: Hawkins et al. (1990). For the exo diastereoisomer (CSD refcode WASWAO) of the title compound, see: Pich et al. (1993). For syn-diol derivatives with inclusion behaviour, see: Kim et al. (2002).

For related literature, see: Bernstein et al. (1995); Carrasco (2001).

Computing details top

Data collection: COLLECT (Nonius, 2000); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: SCALEPACK and DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: WinGX (Farrugia, 1999), PLATON (Spek, 2003) and Mercury (Macrae et al., 2006).

Figures top
[Figure 1] Fig. 1. Asymmetric unit showing displacement ellipsoids at the 30% probability level. Dashed lines represented the disordered H atoms.
[Figure 2] Fig. 2. Two-dimensional network showing the R44(8) and R44(36) rings. Hydrogen atoms not involved in the O—H···O hydrogen bonds have been omitted as well as the disorder.
[Figure 3] Fig. 3. Packing diagram showing two sheets perpendicular to the ac plane. Hydrogen atoms not involved in the O—H···O hydrogen bonds have omitted.
2,6-Dimethyl-9-oxabicyclo[3.3.1]nonane-endo-2,endo-6-diol top
Crystal data top
C10H18O3F(000) = 816
Mr = 186.24Dx = 1.252 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71069 Å
Hall symbol: -C 2ycCell parameters from 11200 reflections
a = 10.8900 (2) Åθ = 2.2–27.5°
b = 9.9227 (2) ŵ = 0.09 mm1
c = 18.8981 (3) ÅT = 170 K
β = 104.658 (11)°Plate, colourless
V = 1975.63 (12) Å30.40 × 0.23 × 0.17 mm
Z = 8
Data collection top
Nonius KappaCCD area-detector
diffractometer
2113 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.032
Horizontally mounted graphite crystal monochromatorθmax = 27.5°, θmin = 2.2°
Detector resolution: 9 pixels mm-1h = 1414
φ and ω scansk = 1212
11200 measured reflectionsl = 2324
2220 independent reflections
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.045H-atom parameters constrained
wR(F2) = 0.122 w = 1/[σ2(Fo2) + (0.0645P)2 + 1.3903P]
where P = (Fo2 + 2Fc2)/3
S = 1.08(Δ/σ)max = 0.001
2220 reflectionsΔρmax = 0.37 e Å3
121 parametersΔρmin = 0.27 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 1997), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.063 (6)
Crystal data top
C10H18O3V = 1975.63 (12) Å3
Mr = 186.24Z = 8
Monoclinic, C2/cMo Kα radiation
a = 10.8900 (2) ŵ = 0.09 mm1
b = 9.9227 (2) ÅT = 170 K
c = 18.8981 (3) Å0.40 × 0.23 × 0.17 mm
β = 104.658 (11)°
Data collection top
Nonius KappaCCD area-detector
diffractometer
2113 reflections with I > 2σ(I)
11200 measured reflectionsRint = 0.032
2220 independent reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0450 restraints
wR(F2) = 0.122H-atom parameters constrained
S = 1.08Δρmax = 0.37 e Å3
2220 reflectionsΔρmin = 0.27 e Å3
121 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
xyzUiso*/UeqOcc. (<1)
O10.14392 (7)0.13828 (8)0.05218 (4)0.0205 (2)
O20.05943 (9)0.06522 (9)0.17721 (5)0.0325 (3)
H20.00680.06690.21830.039*0.50
H120.06880.01560.16370.039*0.50
O30.39487 (9)0.30199 (9)0.19209 (5)0.0329 (3)
H30.41230.36240.16500.039*0.50
H130.46930.27970.21370.039*0.50
C10.08890 (10)0.05681 (11)0.09945 (6)0.0197 (3)
H10.04140.01750.06850.024*
C20.01064 (10)0.14124 (11)0.12572 (6)0.0199 (3)
C30.04768 (10)0.27108 (11)0.16325 (6)0.0203 (3)
H3A0.10060.24930.21270.024*
H3B0.02110.33210.16890.024*
C40.12935 (11)0.34342 (11)0.12003 (6)0.0209 (3)
H4A0.07300.39070.07800.025*
H4B0.18180.41230.15180.025*
C50.21646 (10)0.24856 (11)0.09164 (6)0.0183 (3)
H50.24960.30100.05520.022*
C60.33340 (10)0.19199 (11)0.14790 (6)0.0194 (3)
C70.29534 (11)0.08904 (12)0.19901 (6)0.0214 (3)
H7A0.37150.03800.22500.026*
H7B0.26230.13750.23610.026*
C80.19427 (11)0.01001 (11)0.15796 (6)0.0226 (3)
H8A0.23580.07960.13450.027*
H8B0.15590.05590.19370.027*
C90.12245 (11)0.17108 (14)0.06051 (7)0.0296 (3)
H9A0.15770.08620.03760.044*
H9B0.09340.22600.02480.044*
H9C0.18800.22020.07720.044*
C100.42431 (11)0.13079 (13)0.10697 (7)0.0278 (3)
H10A0.44710.19920.07510.042*
H10B0.38300.05460.07730.042*
H10C0.50120.09930.14230.042*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0249 (4)0.0206 (4)0.0156 (4)0.0001 (3)0.0046 (3)0.0026 (3)
O20.0337 (5)0.0271 (5)0.0423 (5)0.0021 (4)0.0200 (4)0.0106 (4)
O30.0296 (5)0.0241 (5)0.0412 (5)0.0056 (3)0.0023 (4)0.0107 (4)
C10.0224 (5)0.0162 (5)0.0197 (5)0.0001 (4)0.0037 (4)0.0020 (4)
C20.0212 (5)0.0185 (5)0.0201 (5)0.0011 (4)0.0052 (4)0.0016 (4)
C30.0245 (5)0.0170 (5)0.0208 (5)0.0025 (4)0.0082 (4)0.0009 (4)
C40.0248 (6)0.0147 (5)0.0241 (5)0.0034 (4)0.0079 (4)0.0014 (4)
C50.0221 (5)0.0157 (5)0.0174 (5)0.0012 (4)0.0057 (4)0.0012 (4)
C60.0212 (5)0.0156 (5)0.0202 (5)0.0002 (4)0.0031 (4)0.0009 (4)
C70.0233 (5)0.0200 (5)0.0193 (5)0.0026 (4)0.0024 (4)0.0036 (4)
C80.0240 (6)0.0157 (5)0.0273 (6)0.0025 (4)0.0051 (4)0.0028 (4)
C90.0232 (6)0.0329 (7)0.0292 (6)0.0049 (5)0.0000 (5)0.0002 (5)
C100.0246 (6)0.0287 (6)0.0316 (6)0.0063 (5)0.0100 (5)0.0023 (5)
Geometric parameters (Å, º) top
O1—C51.4420 (13)C4—H4A0.9900
O1—C11.4427 (13)C4—H4B0.9900
O2—C21.4352 (13)C5—C61.5433 (14)
O2—H20.8400C5—H51.0000
O2—H120.8400C6—C101.5280 (16)
O3—C61.4331 (13)C6—C71.5332 (15)
O3—H30.8400C7—C81.5320 (16)
O3—H130.8400C7—H7A0.9900
C1—C81.5287 (15)C7—H7B0.9900
C1—C21.5478 (15)C8—H8A0.9900
C1—H11.0000C8—H8B0.9900
C2—C91.5263 (16)C9—H9A0.9800
C2—C31.5292 (15)C9—H9B0.9800
C3—C41.5300 (15)C9—H9C0.9800
C3—H3A0.9900C10—H10A0.9800
C3—H3B0.9900C10—H10B0.9800
C4—C51.5269 (14)C10—H10C0.9800
C5—O1—C1111.34 (8)C4—C5—H5106.6
C2—O2—H2109.5C6—C5—H5106.6
C2—O2—H12109.5O3—C6—C10109.31 (9)
C6—O3—H3109.5O3—C6—C7107.54 (9)
C6—O3—H13109.5C10—C6—C7111.54 (9)
O1—C1—C8109.73 (9)O3—C6—C5107.86 (9)
O1—C1—C2109.25 (8)C10—C6—C5108.85 (9)
C8—C1—C2117.46 (9)C7—C6—C5111.64 (9)
O1—C1—H1106.6C8—C7—C6112.49 (9)
C8—C1—H1106.6C8—C7—H7A109.1
C2—C1—H1106.6C6—C7—H7A109.1
O2—C2—C9107.03 (9)C8—C7—H7B109.1
O2—C2—C3108.05 (9)C6—C7—H7B109.1
C9—C2—C3111.34 (9)H7A—C7—H7B107.8
O2—C2—C1110.03 (9)C1—C8—C7113.55 (9)
C9—C2—C1109.05 (9)C1—C8—H8A108.9
C3—C2—C1111.25 (9)C7—C8—H8A108.9
C2—C3—C4112.14 (9)C1—C8—H8B108.9
C2—C3—H3A109.2C7—C8—H8B108.9
C4—C3—H3A109.2H8A—C8—H8B107.7
C2—C3—H3B109.2C2—C9—H9A109.5
C4—C3—H3B109.2C2—C9—H9B109.5
H3A—C3—H3B107.9H9A—C9—H9B109.5
C5—C4—C3113.28 (9)C2—C9—H9C109.5
C5—C4—H4A108.9H9A—C9—H9C109.5
C3—C4—H4A108.9H9B—C9—H9C109.5
C5—C4—H4B108.9C6—C10—H10A109.5
C3—C4—H4B108.9C6—C10—H10B109.5
H4A—C4—H4B107.7H10A—C10—H10B109.5
O1—C5—C4109.98 (8)C6—C10—H10C109.5
O1—C5—C6109.20 (8)H10A—C10—H10C109.5
C4—C5—C6117.37 (9)H10B—C10—H10C109.5
O1—C5—H5106.6
C5—O1—C1—C864.28 (10)O1—C5—C6—O3173.1 (1)
C5—O1—C1—C265.83 (11)C4—C5—C6—O347.12 (12)
O1—C1—C2—O2175.6 (1)O1—C5—C6—C1068.4 (1)
C8—C1—C2—O249.86 (13)C4—C5—C6—C10165.62 (9)
O1—C1—C2—C967.3 (1)O1—C5—C6—C755.19 (11)
C8—C1—C2—C9166.96 (10)C4—C5—C6—C770.81 (12)
O1—C1—C2—C355.91 (11)O3—C6—C7—C8162.07 (9)
C8—C1—C2—C369.86 (12)C10—C6—C7—C878.10 (12)
O2—C2—C3—C4166.59 (9)C5—C6—C7—C843.94 (12)
C9—C2—C3—C476.15 (12)O1—C1—C8—C751.38 (12)
C1—C2—C3—C445.70 (12)C2—C1—C8—C774.14 (12)
C2—C3—C4—C544.26 (12)C6—C7—C8—C142.51 (13)
C1—O1—C5—C463.63 (10)C1—C2—O2—H279
C1—O1—C5—C666.52 (10)C1—C2—O2—H1239
C3—C4—C5—O152.01 (11)C5—C6—O3—H356
C3—C4—C5—C673.60 (12)C5—C6—O3—H13162
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O2i0.841.922.728 (2)160
O2—H12···O3ii0.841.962.687 (1)145
O3—H3···O2iii0.842.042.687 (1)133
O3—H13···O3iv0.842.022.738 (2)143
Symmetry codes: (i) x, y, z+1/2; (ii) x1/2, y1/2, z; (iii) x+1/2, y+1/2, z; (iv) x+1, y, z+1/2.

Experimental details

Crystal data
Chemical formulaC10H18O3
Mr186.24
Crystal system, space groupMonoclinic, C2/c
Temperature (K)170
a, b, c (Å)10.8900 (2), 9.9227 (2), 18.8981 (3)
β (°) 104.658 (11)
V3)1975.63 (12)
Z8
Radiation typeMo Kα
µ (mm1)0.09
Crystal size (mm)0.40 × 0.23 × 0.17
Data collection
DiffractometerNonius KappaCCD area-detector
Absorption correction
No. of measured, independent and
observed [I > 2σ(I)] reflections
11200, 2220, 2113
Rint0.032
(sin θ/λ)max1)0.650
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.045, 0.122, 1.08
No. of reflections2220
No. of parameters121
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.37, 0.27

Computer programs: COLLECT (Nonius, 2000), SCALEPACK (Otwinowski & Minor, 1997), SCALEPACK and DENZO (Otwinowski & Minor, 1997), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 1997), WinGX (Farrugia, 1999), PLATON (Spek, 2003) and Mercury (Macrae et al., 2006).

Selected torsion angles (º) top
O1—C1—C2—O2175.6 (1)C1—C2—O2—H279
O1—C1—C2—C967.3 (1)C1—C2—O2—H1239
O1—C5—C6—O3173.1 (1)C5—C6—O3—H356
O1—C5—C6—C1068.4 (1)C5—C6—O3—H13162
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2···O2i0.841.922.728 (2)160
O2—H12···O3ii0.841.962.687 (1)145
O3—H3···O2iii0.842.042.687 (1)133
O3—H13···O3iv0.842.022.738 (2)143
Symmetry codes: (i) x, y, z+1/2; (ii) x1/2, y1/2, z; (iii) x+1/2, y+1/2, z; (iv) x+1, y, z+1/2.
 

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