Five bicyclo­[3.3.0]octa-2,6-dienes

A series of five compounds containing the bicyclo­[3.3.0]octa-2,6-diene skeleton are described, namely tetra­methyl cis,cis-3,7-dihydroxy­bicyclo­[3.3.0]octa-2,6-diene-2,4-exo,6,8-exo-tetracarboxyl­ate, C₁₆H₁₈O₁₀, (I), tetra­methyl cis,cis-3,7-di­hydr­oxy-1,5-dimethyl­bicyclo­[3.3.0]octa-2,6-diene-2,4-exo,6,8-exo-tetra­carboxyl­ate, C₁₈H₂₂O₁₀, (II), tetra­methyl cis,cis-3,7-dimethoxybicyclo­[3.3.0]octa-2,6-diene-2,4-exo,6,8-exo-tetra­carboxyl­ate, C₁₈H₂₂O₁₀, (III), tetra­methyl cis,cis-3,7-dimeth­oxy-1,5-dimethyl­bicyclo­[3.3.0]octa-2,6-diene-2,4-exo,6,8-exo-tetra­carboxylate, C₂₀H₂₆O₁₀, (IV), and tetra­methyl cis,cis-3,7-diacetoxy­bicyclo­[3.3.0]octa-2,6-diene-2,4-exo,6,8-exo-tetra­carboxyl­ate, C₂₀H₂₂O₁₂, (V). The bicyclic core is substituted in all cases at positions 2, 4, 6 and 8 with methoxy­carbonyl groups and additionally at positions 3 and 7 with hydroxy [in (I) and (II)], methoxy [in (III) and (IV)] or acet­oxy [in (V)] groups. The conformations of the methoxy­carbonyl groups at positions 2 and 4 are exo for all five compounds. Each C₅ ring of the bicyclic skeleton is almost planar, but the rings are not coplanar, with dihedral angles of 54.93 (7), 69.85 (5), 64.07 (4), 80.74 (5) and 66.91 (7)° for (I)–(V), respectively, and the bicyclooctadiene system adopts a butterfly-like conformation. Strong intra­molecular hydrogen bonds exist between the –OH and C=O groups in (I) and (II), with O...O distances of 2.660 (2) and 2.672 (2) Å in (I), and 2.653 (2) and 2.635 (2) Å in (II). The mol­ecular packing is stabilized by weaker C—H...O(=C) inter­actions, leading to dimers in (I)–(III) and to a chain structure in (V). The structure series presented in this article shows how the geometry of the cycloocta-2,6-diene skeleton changes upon substitution in different positions and, consequently, how the packing is modified, although the intermolecular interactions are basically the same across the series.

S1. Comment

The Weiss reaction is a very general, versatile and simple route to bicyclo[3.3.0]octa-2,6-dienes, which starts from α-diketones reacting with 3-oxoglutarate esters. Although this is a widely used synthetic route, few of the bicyclic compounds derived from it, depicted in the scheme below, have been fully structurally characterized. The structure of the related red Vossen's salt C₁₆H₁₅O₁₀Na, synthetized in 1910 (Vossen, 1910; Schroeter, 1922), was reported only in 2002 (Djaidi et al., 2002). The structures of the two possible epimers when R = H, R'₁ = CH₃ and R'₂ = C₂H₅ have been reported (Williams et al., 1997). The structure of (I) has been previously described in a PhD thesis (Djaidi, 2006), although to the best of our knowledge and from the latest version of the Cambridge Structural Database (specify which version; Allen, 2002), it has been not published. From the synthetic viewpoint, this tetraester could be easily hydrolized and decarboxylated in acid media, leading to bicyclo[3.3.0]octa-3,7-diones (Bertz et al., 1982; Docken, 1981), a versatile starting point for the synthesis of a wide variety of compounds (Gupta et al., 1991).

The series of compounds (Figs. 1–5) are constructed from the central bicyclo[3.3.0]octa-2,6-diene core, with numbering for the nomenclature and the substitution as shown in the scheme. The structure contains two nonconjugated C═C double bonds at positions 2 and 6 and four methoxycarbonyl groups at positions 2, 4, 6 and 8. As expected, from considering conjugation between the double bonds at positions 2 and 6 and the methoxycarbonyl groups at positions 2 and 4, these groups are coplanar with their anchoring carbon rings, with (C1/C3)—C2—C11—(O3/O4) and (C5/C7)—C6—C15—(O7/O8) torsion angles of less than 5°, except for (III) in which some of these angles are ca 15°. Given the planar nature of the methoxycarbonyl groups, two distinct orientations are possible for the methoxy groups at positions 2 and 6, either towards the `bridgehead' side, i.e. internal, or towards the hydroxy group (positions 3 and 7), i.e. external. Both (I) and (II) have internal methoxy groups at the 2- and 6-positions, similar to both epimers of C<sub>17</sub>H<sub>20</sub>O<sub>10</sub> (Williams et al., 1997). In contrast, compounds with substituted hydroxy groups at positions 3 and 7 [(III), (IV) and (V)] have an alternate pattern, with one `internal' and one `external' methoxy group. This situation can be rationalized in terms of the tendency of the OH group to form a hydrogen bond with the methoxycarbonyl C═O group in preference to a methoxy group. Strong intramolecular hydrogen bonds exist between the OH and C═O groups (Desiraju, 2002), with O···O distances of 2.660 (2) and 2.672 (2) Å in (I), and 2.653 (2) and 2.635 (2) Å for (II).

Each one of the two fused five-membered carbon rings in the bicyclic core is almost planar, as indicated by the C—C—C—C torsion angles. As the rings are fused through sp³-like hybridized C atoms they are not coplanar and define dihedral angles of 54.93 (7), 69.85 (5), 64.07 (4), 80.74 (5) and 66.91 (7)° for (I)–(V), respectively, with the bicyclic core conformation best described as butterfly. The positions of the methoxy carbonyl groups on C atoms 4 and 8 are exo in all cases. Additionally, the groups located at C atoms 1 and 5 [H for (I), (III) and (V), and CH₃ for (II) and (IV)] lie at opposite sides of the plane that bisects the carbon unit parallel to the C1—C5 bond, with C10—C5—C1—C9 torsion angles of 25.7 (2) and 25.0 (2)° for (II) and (IV), respectively. For compounds (I)–(IV), the groups connected to atoms O1 and O2 [H for (I) and (II), and CH₃ for (III) and (IV)] are almost coplanar to their rings; according to the C—C—O—C torsion angle data the substituents are inclined at less than 15° for (III) and (IV). In (V), the acetyl group is perpendicular to each pentacyclic unit, with torsion angles close to 90°.

The endo H atoms H4 and H8 play an important role in determining the packing of the five compounds, since they define hydrogen bonds with C═O or OH O atoms on adjacent molecules. In this way, molecules of (I) form dimers through the interaction of atoms H4 and H8 with the OH atom O2A, and of atom H8 with the C═O atom O8A [symmetry code: (A) -x, -y + 2, -z; Fig. 6]. The butterfly wings of the two molecules in these dimers remain parallel, with a separation of ca3.1 Å. The interaction of atom H4 with the OH atom O1(-x + 1, -y, -z) in (II) and of atom H8 with the C═ O atom O4(-x + 1, -y + 1, -z + 2) in (III) leads in the same way to intermolecular dimers (Figs. 7 and 8), but with no parallelism between the butterfly wings. The interactions of atoms H4 and H8 with the C═O atoms O6A and O10A, respectively, in addition to the interaction of atom O1 with H5A, leads to a chain structure for (V) [symmetry code: (A) x, -y + 3/2, -z - 1/2; Fig. 9]. The molecules are positioned in a concave-to-convex arrangement. As the molecules are not planar, the direction of each of the vicinal chains is opposite. This interaction between the endo bicyclic atoms H4 and H8 with other O atoms in the vicinal molecule is not present for (IV), where the packing just contains C_methyl—H···O contacts.

Related literature

For related literature, see: Allen (2002); Arndt (1943); Bertz et al. (1982); Bruker (1999); Desiraju (2002); Djaidi (2006); Djaidi et al. (2002); Docken (1981); Gupta et al. (1991); Schroeter (1922); Vossen (1910); Williams et al. (1997).

S2. Experimental

The synthesis of (I) followed the previously reported protocol of Bertz et al. (1982), slightly modified in order to avoid the formation of sticky byproducts: the Na⁺ salt (C₁₆H₁₆O₁₀Na₂; 26.86 g, 0.065 mol) was dissolved in the minimum amount of distilled water (ca 150 ml). Then, under vigorous stirring, 1 M acetic acid solution was added dropwise (ca 1 ml min^-1); a white solid began to appear, which redissolved quickly (acid addition should be drop by drop, thus avoiding formation of the sticky product), with 128 ml of 1 M acetic acid added in total. The white solid formed was filtered off and redissolved in ethyl acetate, and the resulting solution was dried (MgSO₄), filtered and concentrated under vacuum to obtain a white solid. Recrystallization in acetone gave colorless prismatic crystals in 98% yield [m.p. 383.1–383.8 K (literature 374–376 K; Bertz et al., 1982)].

The synthesis of (II) followed the same procedure described for (I) but starting from C₁₈H₂₀O₁₀Na₂. Recrystallization in acetone gave white [colorless according to CIF] crystals (m.p. 427.1–428.3 K, yield 83%).

Compound (I) (6.00 g, 0.016 mol) or compound (II) (6.0 g, 0.016 mol) was suspended in dry diethyl ether and then treated dropwise with excess diazomethane dissolved in diethyl ether [prepared from N-nitrosomethylurea and KOH as described by (Arndt, 1943)]. The excess diazomethane was allowed to react for 12 h until no more of the reactant (I) or (II) was visible by thin layer chromatography (aluminium foil, silica gel 60 F₂₅₄, ethyl acetate–hexane 1:3). The solution was then evaporated under vacuum to obtain a light-yellow solid, which was redissolved in methanol (250 ml) and allowed to crystallize, yielding 4.87 g of white crystals of (III) (m.p. 411.9–413.2 K, 76.1% yield) or 1.87 g of white crystals [both colorless according to CIF] of (IV) (m.p. 440.7–442.3 K, 87.4%).

For the synthesis of (V), a mixture of acetic acid (40 ml) and acetic anhydride (10 ml, 0.085 mol) was added to (I) (15.38 g, 0.042 mol) and then refluxed [the solid compound (I) dissolves upon heating]. After 40 min, the heat was removed and distilled water (10 ml) was added to the reactor (in small portions with care). The mixture was allowed to cool to room temperature and then extracted with ethyl acetate (50 ml × 3). The extract was then dried with MgSO₄. Evaporation under vacuum lead to 10.2 g of a white powdered solid, which was recrystallized in acetone to give X-ray quality colorless crystals of (V) (m.p. 369.7–371.2 K, 53.4%). When the procedure was applied to (II), no acetylated products were observed.

S3. Refinement

The hydroxy H atoms (where present) were located in a Fourier map and refined with isotropic parameters. For all other H atoms, the H-atom positions were calculated after each cycle of refinement with SHELXTL-NT (Bruker, 1999) using a riding model for each structure, with C—H distances in the range 0.96–1.00 Å. U_iso(H) values were set equal to 1.5U_eq of the parent C atom for methyl groups and 1.2U_eq(C) for other H atoms.

Computing details

For all compounds, data collection: SMART-NT (Bruker, 2001); cell refinement: SAINT-NT (Bruker, 1999); data reduction: SAINT-NT (Bruker, 1999); program(s) used to solve structure: SHELXTL-NT (Bruker, 1999); program(s) used to refine structure: SHELXTL-NT (Bruker, 1999); molecular graphics: SHELXTL-NT (Bruker, 1999); software used to prepare material for publication: SHELXTL-NT (Bruker, 1999).

Figures

	Fig. 1. The molecular structure of (I), with the atomic numbering scheme. Displacement ellipsoids are shown at the 33% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 2. The molecular structure of (II), with the atomic numbering scheme. Displacement ellipsoids are shown at the 33% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 3. The molecular structure of (III), with the atomic numbering scheme. Displacement ellipsoids are shown at the 33% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 4. The molecular structure of (IV), with the atomic numbering scheme. Displacement ellipsoids are shown at the 33% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 5. The molecular structure of (V), with the atomic numbering scheme. Displacement ellipsoids are shown at the 33% probability level and H atoms are shown as spheres of arbitrary radii.
	Fig. 6. The molecular packing for (I) [symmetry code: (A) -x, -y + 2, -z]. C atoms are plotted as cross-hatched circles, O atoms as shaded circles and H atoms as circles. Some of the H atoms have been omitted for clarity.
	Fig. 7. The molecular packing for (II) [symmetry code: (A) -x + 1, -y, -z]. Atoms are represented as in Fig. 6. Some of the H atoms have been omitted for clarity.
	Fig. 8. The molecular packing for (III) [symmetry code: (A) -x + 1, -y + 1, -z + 2]. Atoms are represented as in Fig. 6. Some of the H atoms have been omitted for clarity.
	Fig. 9. The molecular packing for (V) [symmetry code: (A) x, -y + 3/2, -z - 1/2]. Atoms are represented as in Fig. 6. Some of the H atoms and some atoms not involved in the interactions shown have been omitted for clarity.

(I) tetramethyl cis,cis-3,7-dihydroxybicyclo[3.3.0]octa-2,6-diene- 2,4-exo,6,8-exo-tetracarboxylate

Crystal data

C16H18O10	F(000) = 776
Mr = 370.30	Dx = 1.437 Mg m^−3
Monoclinic, P21/n	Melting point: 109.9-110.6 (literature: 101-103) K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 12.1198 (18) Å	Cell parameters from 4350 reflections
b = 12.5461 (19) Å	θ = 2.4–24.6°
c = 12.4089 (19) Å	µ = 0.12 mm^−1
β = 114.896 (2)°	T = 150 K
V = 1711.5 (4) Å^3	Polyhedron, colorless
Z = 4	0.55 × 0.21 × 0.13 mm

Data collection

Siemens SMART CCD area-detector diffractometer	3025 independent reflections
Radiation source: fine-focus sealed tube	2583 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.028
ϕ and ω scans	θmax = 25.0°, θmin = 2.0°
Absorption correction: part of the refinement model (ΔF) (SADABS; Bruker, 1999)	h = −14→14
Tmin = 0.935, Tmax = 0.984	k = −14→14
11440 measured reflections	l = −14→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.038	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.104	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0542P)^2 + 0.4889P] where P = (Fo^2 + 2Fc^2)/3
3025 reflections	(Δ/σ)max < 0.001
247 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.17 e Å^−3

Special details

Experimental. 0.3 ° between frames and 20 secs exposure (per frame)

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 5.3133 (0.0085) x + 9.3621 (0.0067) y - 3.3488 (0.0093) z = 6.4064 (0.0058)

* 0.0684 (0.0009) C1 * -0.0241 (0.0010) C2 * -0.0321 (0.0010) C3 * 0.0722 (0.0010) C4 * -0.0844 (0.0010) C5

Rms deviation of fitted atoms = 0.0611

0.6438 (0.0092) x + 1.7209 (0.0094) y - 11.4108 (0.0041) z = 0.1212 (0.0085)

Angle to previous plane (with approximate e.s.d.) = 54.93 (0.07)

* -0.0965 (0.0009) C1 * 0.0676 (0.0009) C5 * -0.0076 (0.0010) C6 * -0.0571 (0.0010) C7 * 0.0936 (0.0009) C8

Rms deviation of fitted atoms = 0.0721

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.08396 (12)	0.67107 (10)	−0.15219 (10)	0.0353 (3)
H1	0.021 (2)	0.628 (2)	−0.166 (2)	0.066 (7)*
C3	0.10211 (14)	0.72085 (13)	−0.05023 (14)	0.0271 (4)
C2	0.03770 (14)	0.70816 (12)	0.01409 (14)	0.0257 (4)
C11	−0.06461 (14)	0.63584 (13)	−0.02446 (14)	0.0282 (4)
O3	−0.12524 (10)	0.63914 (9)	0.04394 (10)	0.0333 (3)
C12	−0.23401 (17)	0.57417 (18)	0.00448 (19)	0.0489 (5)
H12A	−0.2954	0.6029	−0.0701	0.073*
H12B	−0.2660	0.5748	0.0650	0.073*
H12C	−0.2142	0.5008	−0.0082	0.073*
O4	−0.09395 (11)	0.57884 (10)	−0.11209 (11)	0.0388 (3)
C1	0.08088 (13)	0.78046 (12)	0.12010 (13)	0.0239 (3)
H1A	0.1007	0.7384	0.1944	0.029*
C8	−0.00569 (14)	0.87491 (12)	0.11280 (14)	0.0243 (3)
H8	−0.0681	0.8829	0.0291	0.029*
C17	−0.06830 (15)	0.86531 (13)	0.19472 (15)	0.0283 (4)
O9	−0.18756 (11)	0.88028 (12)	0.13618 (12)	0.0475 (4)
C18	−0.2562 (2)	0.8716 (2)	0.2077 (2)	0.0687 (7)
H18A	−0.2369	0.8039	0.2510	0.103*
H18B	−0.3435	0.8743	0.1558	0.103*
H18C	−0.2347	0.9309	0.2644	0.103*
O10	−0.01788 (11)	0.84805 (11)	0.29918 (11)	0.0410 (3)
C7	0.07960 (14)	0.96797 (12)	0.14486 (13)	0.0243 (3)
O2	0.04152 (11)	1.06242 (9)	0.16719 (10)	0.0302 (3)
H2	0.101 (2)	1.1046 (17)	0.1811 (19)	0.050 (6)*
C6	0.18732 (14)	0.94655 (12)	0.14337 (13)	0.0253 (4)
C15	0.27344 (14)	1.03093 (13)	0.15769 (13)	0.0268 (4)
O7	0.37033 (10)	0.99862 (9)	0.14229 (10)	0.0318 (3)
C16	0.45486 (16)	1.08030 (15)	0.14306 (17)	0.0400 (5)
H16A	0.4096	1.1413	0.0957	0.060*
H16B	0.5085	1.0516	0.1090	0.060*
H16C	0.5038	1.1033	0.2250	0.060*
O8	0.25581 (10)	1.12375 (9)	0.17749 (10)	0.0332 (3)
C5	0.19878 (14)	0.83101 (12)	0.12000 (14)	0.0248 (3)
H5	0.2724	0.8000	0.1858	0.030*
C4	0.19947 (15)	0.80432 (13)	−0.00252 (14)	0.0277 (4)
H4	0.1729	0.8688	−0.0546	0.033*
C13	0.32245 (15)	0.76896 (13)	0.00656 (15)	0.0312 (4)
O5	0.35769 (10)	0.67789 (10)	0.06738 (11)	0.0368 (3)
C14	0.47507 (17)	0.63754 (17)	0.08232 (18)	0.0442 (5)
H14A	0.4806	0.6391	0.0058	0.066*
H14B	0.4847	0.5641	0.1117	0.066*
H14C	0.5395	0.6821	0.1396	0.066*
O6	0.38111 (14)	0.81581 (11)	−0.03460 (15)	0.0553 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0374 (7)	0.0412 (7)	0.0309 (7)	−0.0030 (6)	0.0178 (6)	−0.0086 (5)
C3	0.0293 (8)	0.0265 (8)	0.0246 (8)	0.0037 (7)	0.0106 (7)	0.0001 (7)
C2	0.0261 (8)	0.0246 (8)	0.0258 (8)	0.0014 (6)	0.0103 (7)	0.0010 (6)
C11	0.0261 (8)	0.0286 (8)	0.0279 (9)	0.0013 (7)	0.0095 (7)	0.0016 (7)
O3	0.0278 (6)	0.0372 (7)	0.0357 (7)	−0.0074 (5)	0.0141 (5)	−0.0008 (5)
C12	0.0317 (10)	0.0584 (13)	0.0553 (13)	−0.0152 (9)	0.0170 (9)	−0.0002 (10)
O4	0.0369 (7)	0.0390 (7)	0.0349 (7)	−0.0060 (6)	0.0097 (6)	−0.0087 (6)
C1	0.0246 (8)	0.0230 (8)	0.0247 (8)	−0.0006 (6)	0.0109 (7)	0.0014 (6)
C8	0.0244 (8)	0.0259 (8)	0.0230 (8)	0.0005 (6)	0.0105 (7)	0.0011 (6)
C17	0.0303 (9)	0.0267 (8)	0.0305 (9)	−0.0003 (7)	0.0153 (7)	−0.0008 (7)
O9	0.0307 (7)	0.0768 (10)	0.0416 (8)	0.0106 (6)	0.0217 (6)	0.0087 (7)
C18	0.0403 (12)	0.120 (2)	0.0616 (15)	0.0090 (13)	0.0369 (11)	0.0088 (14)
O10	0.0396 (7)	0.0585 (9)	0.0292 (7)	−0.0015 (6)	0.0185 (6)	0.0032 (6)
C7	0.0295 (8)	0.0238 (8)	0.0200 (8)	0.0016 (6)	0.0108 (7)	0.0017 (6)
O2	0.0341 (7)	0.0250 (6)	0.0341 (7)	0.0010 (5)	0.0169 (5)	−0.0020 (5)
C6	0.0265 (8)	0.0264 (8)	0.0225 (8)	−0.0011 (6)	0.0098 (7)	0.0003 (6)
C15	0.0273 (8)	0.0302 (9)	0.0215 (8)	−0.0021 (7)	0.0089 (7)	−0.0004 (7)
O7	0.0311 (6)	0.0305 (6)	0.0385 (7)	−0.0069 (5)	0.0193 (5)	−0.0038 (5)
C16	0.0380 (10)	0.0398 (11)	0.0487 (11)	−0.0128 (8)	0.0247 (9)	−0.0047 (9)
O8	0.0353 (7)	0.0267 (7)	0.0372 (7)	−0.0050 (5)	0.0150 (6)	−0.0067 (5)
C5	0.0237 (8)	0.0258 (8)	0.0261 (8)	0.0005 (6)	0.0115 (7)	0.0005 (6)
C4	0.0325 (9)	0.0250 (8)	0.0296 (9)	0.0007 (7)	0.0169 (7)	0.0018 (7)
C13	0.0349 (9)	0.0298 (9)	0.0347 (9)	−0.0038 (7)	0.0202 (8)	−0.0039 (7)
O5	0.0305 (7)	0.0409 (7)	0.0444 (7)	0.0069 (5)	0.0210 (6)	0.0067 (6)
C14	0.0330 (10)	0.0571 (13)	0.0479 (11)	0.0107 (9)	0.0222 (9)	0.0005 (9)
O6	0.0634 (9)	0.0426 (8)	0.0884 (11)	0.0010 (7)	0.0599 (9)	0.0089 (7)

Geometric parameters (Å, º)

C1—C2	1.499 (2)	O9—C18	1.454 (2)
C1—C8	1.560 (2)	C18—H18A	0.9800
C1—C5	1.564 (2)	C18—H18B	0.9800
C2—C3	1.340 (2)	C18—H18C	0.9800
C3—C4	1.500 (2)	C7—O2	1.3422 (19)
C4—C5	1.560 (2)	O2—H2	0.85 (2)
C5—C6	1.496 (2)	C6—C15	1.444 (2)
C6—C7	1.341 (2)	C15—O8	1.227 (2)
C7—C8	1.498 (2)	C15—O7	1.330 (2)
O1—C3	1.3435 (19)	O7—C16	1.446 (2)
O1—H1	0.89 (2)	C16—H16A	0.9800
C2—C11	1.446 (2)	C16—H16B	0.9800
C11—O4	1.223 (2)	C16—H16C	0.9800
C11—O3	1.337 (2)	C5—H5	1.0000
O3—C12	1.449 (2)	C4—C13	1.513 (2)
C12—H12A	0.9800	C4—H4	1.0000
C12—H12B	0.9800	C13—O6	1.191 (2)
C12—H12C	0.9800	C13—O5	1.336 (2)
C1—H1A	1.0000	O5—C14	1.447 (2)
C8—C17	1.508 (2)	C14—H14A	0.9800
C8—H8	1.0000	C14—H14B	0.9800
C17—O10	1.197 (2)	C14—H14C	0.9800
C17—O9	1.330 (2)	O1—O2	6.465 (2)
C3—O1—H1	104.8 (16)	C6—C7—O2	126.96 (15)
C2—C3—O1	126.88 (15)	C6—C7—C8	114.03 (14)
C2—C3—C4	113.97 (14)	O2—C7—C8	118.96 (13)
O1—C3—C4	119.07 (14)	C7—O2—H2	104.6 (14)
C3—C2—C11	120.72 (14)	C7—C6—C15	120.59 (15)
C3—C2—C1	112.03 (14)	C7—C6—C5	111.55 (14)
C11—C2—C1	127.16 (14)	C15—C6—C5	127.79 (14)
O4—C11—O3	123.43 (15)	O8—C15—O7	123.83 (15)
O4—C11—C2	123.31 (15)	O8—C15—C6	122.84 (15)
O3—C11—C2	113.24 (14)	O7—C15—C6	113.27 (14)
C11—O3—C12	115.66 (14)	C15—O7—C16	116.67 (13)
O3—C12—H12A	109.5	O7—C16—H16A	109.5
O3—C12—H12B	109.5	O7—C16—H16B	109.5
H12A—C12—H12B	109.5	H16A—C16—H16B	109.5
O3—C12—H12C	109.5	O7—C16—H16C	109.5
H12A—C12—H12C	109.5	H16A—C16—H16C	109.5
H12B—C12—H12C	109.5	H16B—C16—H16C	109.5
C2—C1—C8	115.52 (12)	C6—C5—C4	115.84 (13)
C2—C1—C5	103.07 (12)	C6—C5—C1	103.49 (12)
C8—C1—C5	106.52 (12)	C4—C5—C1	107.07 (12)
C2—C1—H1A	110.5	C6—C5—H5	110.0
C8—C1—H1A	110.5	C4—C5—H5	110.0
C5—C1—H1A	110.5	C1—C5—H5	110.0
C7—C8—C17	111.73 (13)	C3—C4—C13	114.28 (13)
C7—C8—C1	101.81 (12)	C3—C4—C5	102.03 (12)
C17—C8—C1	114.66 (12)	C13—C4—C5	113.55 (13)
C7—C8—H8	109.5	C3—C4—H4	108.9
C17—C8—H8	109.5	C13—C4—H4	108.9
C1—C8—H8	109.5	C5—C4—H4	108.9
O10—C17—O9	123.99 (15)	O6—C13—O5	123.90 (16)
O10—C17—C8	124.89 (15)	O6—C13—C4	124.80 (16)
O9—C17—C8	111.12 (14)	O5—C13—C4	111.30 (13)
C17—O9—C18	115.22 (15)	C13—O5—C14	115.77 (14)
O9—C18—H18A	109.5	O5—C14—H14A	109.5
O9—C18—H18B	109.5	O5—C14—H14B	109.5
H18A—C18—H18B	109.5	H14A—C14—H14B	109.5
O9—C18—H18C	109.5	O5—C14—H14C	109.5
H18A—C18—H18C	109.5	H14A—C14—H14C	109.5
H18B—C18—H18C	109.5	H14B—C14—H14C	109.5
C1—C2—C3—C4	−0.85 (19)	C7—C8—C17—O9	115.38 (15)
C1—C5—C4—C3	−13.02 (15)	C1—C8—C17—O9	−129.45 (15)
C2—C3—C4—C5	8.92 (18)	O10—C17—O9—C18	−1.5 (3)
C3—C4—C5—C6	−127.85 (14)	C8—C17—O9—C18	179.49 (18)
C4—C5—C6—C7	111.08 (15)	C17—C8—C7—C6	136.16 (14)
C5—C6—C7—C8	−5.02 (19)	C17—C8—C7—O2	−46.24 (18)
C6—C7—C8—C1	13.33 (17)	C1—C8—C7—O2	−169.07 (13)
C7—C8—C5—C1	163.03 (16)	O2—C7—C6—C15	−5.1 (2)
C1—C2—C11—O3	1.6 (2)	C8—C7—C6—C15	172.25 (13)
C1—C2—C11—O4	−179.69 (15)	O2—C7—C6—C5	177.61 (14)
C3—C2—C11—O3	−174.64 (14)	O8—C15—O7—C16	−3.4 (2)
C3—C2—C11—O4	4.1 (2)	C6—C15—O7—C16	173.86 (13)
C5—C6—C15—O7	3.1 (2)	C15—C6—C5—C4	−65.9 (2)
C5—C6—C15—O8	−179.52 (15)	C7—C6—C5—C1	−5.76 (17)
C7—C6—C15—O7	−173.64 (14)	C15—C6—C5—C1	177.21 (14)
C7—C6—C15—O8	3.7 (2)	C2—C1—C5—C6	135.61 (12)
O1—C3—C2—C11	−0.8 (3)	C8—C1—C5—C6	13.59 (15)
C4—C3—C2—C11	175.89 (14)	C2—C1—C5—C4	12.76 (15)
O1—C3—C2—C1	−177.57 (14)	C8—C1—C5—C4	−109.27 (13)
O4—C11—O3—C12	−3.2 (2)	C2—C3—C4—C13	131.89 (15)
C2—C11—O3—C12	175.60 (14)	O1—C3—C4—C13	−51.1 (2)
C3—C2—C1—C8	108.09 (15)	O1—C3—C4—C5	−174.08 (13)
C11—C2—C1—C8	−68.4 (2)	C6—C5—C4—C13	108.69 (16)
C3—C2—C1—C5	−7.65 (17)	C1—C5—C4—C13	−136.49 (13)
C11—C2—C1—C5	175.87 (15)	C3—C4—C13—O6	127.25 (19)
C2—C1—C8—C7	−129.63 (13)	C5—C4—C13—O6	−116.27 (19)
C2—C1—C8—C17	109.56 (15)	C3—C4—C13—O5	−52.93 (18)
C5—C1—C8—C17	−136.67 (13)	C5—C4—C13—O5	63.55 (18)
C7—C8—C17—O10	−63.6 (2)	O6—C13—O5—C14	0.4 (3)
C1—C8—C17—O10	51.6 (2)	C4—C13—O5—C14	−179.39 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4	0.89 (2)	1.89 (2)	2.6720 (18)	146 (2)
O2—H2···O8	0.85 (2)	1.91 (2)	2.6597 (17)	146 (2)
C8—H8···O8^i	1.00	2.62	3.602 (2)	169
C4—H4···O2^i	1.00	2.53	3.237 (2)	128

Symmetry code: (i) −x, −y+2, −z.

(II) tetramethyl cis,cis-3,7-dihydroxy-1,5-dimethylbicyclo[3.3.0]octa-2,6-diene- 2,4-exo,6,8-exo-tetracarboxylate

Crystal data

C18H22O10	Z = 2
Mr = 398.36	F(000) = 420
Triclinic, P1	Dx = 1.441 Mg m^−3
Hall symbol: -P 1	Melting point = 153.9–155.1 K
a = 9.3037 (6) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.2495 (7) Å	Cell parameters from 3771 reflections
c = 10.6378 (7) Å	θ = 2.4–25.0°
α = 95.155 (1)°	µ = 0.12 mm^−1
β = 103.114 (1)°	T = 150 K
γ = 109.208 (1)°	Plate, colorless
V = 917.90 (11) Å^3	0.55 × 0.42 × 0.39 mm

Data collection

Siemens SMART CCD area-detector diffractometer	3209 independent reflections
Radiation source: fine-focus sealed tube	2900 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.011
ϕ and ω scans	θmax = 25.0°, θmin = 2.0°
Absorption correction: part of the refinement model (ΔF) (SADABS; Bruker, 1999)	h = −10→11
Tmin = 0.938, Tmax = 0.955	k = −12→12
5494 measured reflections	l = −12→12

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0517P)^2 + 0.2879P] where P = (Fo^2 + 2Fc^2)/3
3209 reflections	(Δ/σ)max < 0.001
267 parameters	Δρmax = 0.26 e Å^−3
0 restraints	Δρmin = −0.19 e Å^−3

Special details

Experimental. 0.3 ° between frames and 10 secs exposure (per frame)

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

6.0204 (0.0048) x + 2.2059 (0.0067) y + 3.8463 (0.0066) z = 5.3360 (0.0033)

* 0.1125 (0.0008) C1 * -0.0563 (0.0009) C2 * -0.0291 (0.0009) C3 * 0.0998 (0.0008) C4 * -0.1270 (0.0008) C5

Rms deviation of fitted atoms = 0.0925

- 2.9505 (0.0059) x + 10.0137 (0.0016) y + 1.2263 (0.0070) z = 2.3261 (0.0044)

Angle to previous plane (with approximate e.s.d.) = 69.85 (0.05)

* -0.1342 (0.0008) C1 * 0.1123 (0.0008) C5 * -0.0474 (0.0009) C6 * -0.0429 (0.0009) C7 * 0.1121 (0.0008) C8

Rms deviation of fitted atoms = 0.0972

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.47110 (13)	−0.03840 (11)	0.64565 (11)	0.0343 (3)
H1	0.444 (3)	−0.097 (2)	0.700 (2)	0.059 (6)*
C3	0.42416 (16)	0.06705 (14)	0.67737 (14)	0.0245 (3)
C2	0.35393 (16)	0.08153 (14)	0.77191 (13)	0.0223 (3)
C11	0.32632 (16)	−0.02376 (14)	0.85577 (14)	0.0252 (3)
O3	0.26444 (12)	0.00529 (10)	0.95135 (10)	0.0283 (2)
C12	0.2378 (2)	−0.09603 (17)	1.03841 (16)	0.0357 (4)
H12A	0.3303	−0.1198	1.0656	0.054*
H12B	0.1491	−0.1791	0.9932	0.054*
H12C	0.2164	−0.0562	1.1141	0.054*
O4	0.35934 (13)	−0.12941 (11)	0.84071 (11)	0.0339 (3)
C1	0.32496 (16)	0.21882 (14)	0.78241 (13)	0.0211 (3)
C9	0.43802 (16)	0.32010 (15)	0.90647 (13)	0.0257 (3)
H9A	0.5452	0.3362	0.9049	0.039*
H9B	0.4192	0.2802	0.9821	0.039*
H9C	0.4207	0.4075	0.9103	0.039*
C8	0.14584 (16)	0.19194 (14)	0.77181 (13)	0.0220 (3)
H8	0.0993	0.1040	0.8019	0.026*
C17	0.12153 (16)	0.31047 (15)	0.85034 (13)	0.0236 (3)
O5	0.12808 (11)	0.41840 (10)	0.78764 (9)	0.0270 (2)
O6	0.10362 (13)	0.30880 (12)	0.95871 (10)	0.0345 (3)
C18	0.1098 (2)	0.53684 (16)	0.85877 (16)	0.0350 (4)
H18A	0.1839	0.5655	0.9441	0.052*
H18B	0.0041	0.5100	0.8678	0.052*
H18C	0.1292	0.6134	0.8114	0.052*
C7	0.07620 (16)	0.17361 (14)	0.62748 (13)	0.0221 (3)
O2	−0.08155 (11)	0.12242 (10)	0.58052 (11)	0.0283 (2)
H2	−0.098 (2)	0.122 (2)	0.494 (2)	0.052 (6)*
C6	0.18437 (16)	0.21328 (14)	0.56018 (13)	0.0222 (3)
C15	0.13283 (17)	0.20624 (14)	0.41931 (14)	0.0256 (3)
O7	0.25047 (12)	0.24851 (11)	0.36285 (9)	0.0307 (3)
C16	0.2043 (2)	0.24296 (18)	0.22255 (15)	0.0393 (4)
H16A	0.1616	0.3148	0.2041	0.059*
H16B	0.1255	0.1527	0.1811	0.059*
H16C	0.2950	0.2577	0.1893	0.059*
O8	−0.00707 (12)	0.16525 (11)	0.35739 (10)	0.0334 (3)
C5	0.35250 (15)	0.26790 (14)	0.64888 (13)	0.0213 (3)
C10	0.42970 (16)	0.42702 (14)	0.65991 (14)	0.0250 (3)
H10A	0.3675	0.4727	0.6932	0.038*
H10B	0.4357	0.4487	0.5749	0.038*
H10C	0.5343	0.4594	0.7186	0.038*
C4	0.45074 (16)	0.18468 (14)	0.60182 (13)	0.0234 (3)
H4	0.4069	0.1473	0.5076	0.028*
C13	0.62584 (16)	0.27294 (14)	0.63150 (14)	0.0250 (3)
O9	0.65751 (11)	0.32465 (10)	0.52558 (10)	0.0293 (2)
C14	0.81879 (18)	0.41577 (17)	0.54256 (17)	0.0358 (4)
H14A	0.8891	0.3690	0.5769	0.054*
H14B	0.8421	0.5004	0.6026	0.054*
H14C	0.8325	0.4386	0.4594	0.054*
O10	0.72156 (12)	0.29710 (12)	0.73569 (11)	0.0357 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0460 (7)	0.0266 (6)	0.0402 (6)	0.0193 (5)	0.0207 (5)	0.0081 (5)
C3	0.0245 (7)	0.0214 (7)	0.0262 (7)	0.0078 (6)	0.0051 (6)	0.0026 (6)
C2	0.0223 (7)	0.0207 (7)	0.0222 (7)	0.0067 (5)	0.0043 (5)	0.0038 (5)
C11	0.0220 (7)	0.0243 (7)	0.0276 (7)	0.0076 (6)	0.0044 (6)	0.0052 (6)
O3	0.0343 (6)	0.0283 (5)	0.0263 (5)	0.0124 (4)	0.0115 (4)	0.0117 (4)
C12	0.0420 (9)	0.0356 (9)	0.0348 (9)	0.0135 (7)	0.0166 (7)	0.0185 (7)
O4	0.0394 (6)	0.0266 (6)	0.0435 (6)	0.0163 (5)	0.0168 (5)	0.0145 (5)
C1	0.0225 (7)	0.0196 (7)	0.0207 (7)	0.0070 (5)	0.0055 (5)	0.0047 (5)
C9	0.0273 (7)	0.0261 (7)	0.0209 (7)	0.0082 (6)	0.0040 (6)	0.0026 (6)
C8	0.0233 (7)	0.0205 (7)	0.0214 (7)	0.0065 (5)	0.0059 (5)	0.0051 (5)
C17	0.0202 (7)	0.0272 (7)	0.0225 (7)	0.0080 (6)	0.0050 (5)	0.0041 (6)
O5	0.0327 (6)	0.0237 (5)	0.0276 (5)	0.0125 (4)	0.0103 (4)	0.0046 (4)
O6	0.0419 (6)	0.0432 (6)	0.0248 (6)	0.0199 (5)	0.0140 (5)	0.0076 (5)
C18	0.0405 (9)	0.0268 (8)	0.0382 (9)	0.0156 (7)	0.0093 (7)	−0.0014 (7)
C7	0.0229 (7)	0.0173 (6)	0.0231 (7)	0.0066 (5)	0.0025 (5)	0.0016 (5)
O2	0.0215 (5)	0.0303 (6)	0.0282 (6)	0.0063 (4)	0.0029 (4)	0.0031 (4)
C6	0.0251 (7)	0.0196 (7)	0.0204 (7)	0.0078 (5)	0.0041 (6)	0.0028 (5)
C15	0.0311 (8)	0.0207 (7)	0.0225 (7)	0.0084 (6)	0.0040 (6)	0.0038 (6)
O7	0.0341 (6)	0.0372 (6)	0.0194 (5)	0.0102 (5)	0.0073 (4)	0.0085 (4)
C16	0.0522 (10)	0.0440 (10)	0.0198 (8)	0.0142 (8)	0.0097 (7)	0.0078 (7)
O8	0.0302 (6)	0.0371 (6)	0.0248 (5)	0.0082 (5)	−0.0018 (4)	0.0044 (4)
C5	0.0231 (7)	0.0219 (7)	0.0179 (7)	0.0071 (6)	0.0051 (5)	0.0039 (5)
C10	0.0262 (7)	0.0222 (7)	0.0266 (7)	0.0076 (6)	0.0078 (6)	0.0063 (6)
C4	0.0258 (7)	0.0236 (7)	0.0204 (7)	0.0084 (6)	0.0065 (6)	0.0035 (5)
C13	0.0270 (7)	0.0241 (7)	0.0270 (8)	0.0114 (6)	0.0095 (6)	0.0059 (6)
O9	0.0262 (5)	0.0321 (6)	0.0306 (6)	0.0081 (4)	0.0107 (4)	0.0119 (4)
C14	0.0274 (8)	0.0380 (9)	0.0452 (9)	0.0104 (7)	0.0141 (7)	0.0179 (7)
O10	0.0265 (6)	0.0464 (7)	0.0316 (6)	0.0101 (5)	0.0054 (5)	0.0117 (5)

Geometric parameters (Å, º)

C1—C2	1.5166 (19)	O5—C18	1.4508 (17)
C1—C8	1.5725 (18)	C18—H18A	0.9600
C1—C5	1.5954 (18)	C18—H18B	0.9600
C2—C3	1.340 (2)	C18—H18C	0.9600
C3—C4	1.4928 (19)	C7—O2	1.3388 (16)
C4—C5	1.5676 (19)	O2—H2	0.89 (2)
C5—C6	1.5198 (18)	C6—C15	1.4534 (19)
C6—C7	1.342 (2)	C15—O8	1.2272 (17)
C7—C8	1.4929 (19)	C15—O7	1.3339 (18)
O1—C3	1.3359 (17)	O7—C16	1.4467 (17)
O1—H1	0.89 (2)	C16—H16A	0.9600
C2—C11	1.4563 (19)	C16—H16B	0.9600
C11—O4	1.2258 (17)	C16—H16C	0.9600
C11—O3	1.3335 (18)	C5—C10	1.5317 (18)
O3—C12	1.4509 (17)	C10—H10A	0.9600
C12—H12A	0.9600	C10—H10B	0.9600
C12—H12B	0.9600	C10—H10C	0.9600
C12—H12C	0.9600	C4—C13	1.5224 (19)
C1—C9	1.5268 (19)	C4—H4	0.9800
C9—H9A	0.9600	C13—O10	1.2002 (17)
C9—H9B	0.9600	C13—O9	1.3388 (17)
C9—H9C	0.9600	O9—C14	1.4425 (18)
C8—C17	1.5197 (19)	C14—H14A	0.9600
C8—H8	0.9800	C14—H14B	0.9600
C17—O6	1.2024 (17)	C14—H14C	0.9600
C17—O5	1.3338 (17)	O1—O2	5.814 (2)
C3—O1—H1	104.8 (14)	O2—C7—C6	127.85 (13)
O1—C3—C2	127.35 (13)	O2—C7—C8	118.33 (12)
O1—C3—C4	118.52 (13)	C6—C7—C8	113.81 (12)
C2—C3—C4	114.12 (12)	C7—O2—H2	103.9 (13)
C3—C2—C11	119.53 (13)	C7—C6—C15	119.60 (13)
C3—C2—C1	112.03 (12)	C7—C6—C5	112.24 (12)
C11—C2—C1	128.25 (12)	C15—C6—C5	128.10 (12)
O4—C11—O3	122.82 (13)	O8—C15—O7	122.73 (13)
O4—C11—C2	122.69 (13)	O8—C15—C6	122.92 (14)
O3—C11—C2	114.48 (12)	O7—C15—C6	114.36 (12)
C11—O3—C12	116.09 (12)	C15—O7—C16	116.14 (12)
O3—C12—H12A	109.5	O7—C16—H16A	109.5
O3—C12—H12B	109.5	O7—C16—H16B	109.5
H12A—C12—H12B	109.5	H16A—C16—H16B	109.5
O3—C12—H12C	109.5	O7—C16—H16C	109.5
H12A—C12—H12C	109.5	H16A—C16—H16C	109.5
H12B—C12—H12C	109.5	H16B—C16—H16C	109.5
C2—C1—C9	110.38 (11)	C6—C5—C10	111.05 (11)
C2—C1—C8	110.83 (10)	C6—C5—C4	110.38 (10)
C9—C1—C8	113.42 (11)	C10—C5—C4	113.12 (11)
C2—C1—C5	101.62 (10)	C6—C5—C1	101.56 (10)
C9—C1—C5	114.48 (11)	C10—C5—C1	114.39 (11)
C8—C1—C5	105.42 (10)	C4—C5—C1	105.64 (10)
C1—C9—H9A	109.5	C5—C10—H10A	109.5
C1—C9—H9B	109.5	C5—C10—H10B	109.5
H9A—C9—H9B	109.5	H10A—C10—H10B	109.5
C1—C9—H9C	109.5	C5—C10—H10C	109.5
H9A—C9—H9C	109.5	H10A—C10—H10C	109.5
H9B—C9—H9C	109.5	H10B—C10—H10C	109.5
C7—C8—C17	113.20 (11)	C3—C4—C13	111.43 (11)
C7—C8—C1	102.45 (11)	C3—C4—C5	102.49 (11)
C17—C8—C1	113.08 (11)	C13—C4—C5	112.91 (11)
C7—C8—H8	109.3	C3—C4—H4	109.9
C17—C8—H8	109.3	C13—C4—H4	109.9
C1—C8—H8	109.3	C5—C4—H4	109.9
O6—C17—O5	123.86 (13)	O10—C13—O9	124.44 (13)
O6—C17—C8	123.62 (13)	O10—C13—C4	125.32 (13)
O5—C17—C8	112.48 (11)	O9—C13—C4	110.20 (11)
C17—O5—C18	115.30 (11)	C13—O9—C14	115.75 (11)
O5—C18—H18A	109.5	O9—C14—H14A	109.5
O5—C18—H18B	109.5	O9—C14—H14B	109.5
H18A—C18—H18B	109.5	H14A—C14—H14B	109.5
O5—C18—H18C	109.5	O9—C14—H14C	109.5
H18A—C18—H18C	109.5	H14A—C14—H14C	109.5
H18B—C18—H18C	109.5	H14B—C14—H14C	109.5
C1—C2—C3—C4	−2.47 (17)	O6—C17—O5—C18	−0.81 (19)
C1—C5—C4—C3	18.44 (13)	C8—C17—O5—C18	−178.50 (11)
C2—C3—C4—C5	−10.61 (15)	C17—C8—C7—O2	−70.42 (15)
C3—C4—C5—C6	−90.58 (12)	C1—C8—C7—O2	167.48 (11)
C4—C5—C6—C7	124.75 (12)	C17—C8—C7—C6	109.04 (14)
C5—C6—C7—C8	−0.16 (17)	O2—C7—C6—C15	1.8 (2)
C6—C7—C8—C1	−13.05 (15)	C8—C7—C6—C15	−177.60 (11)
C7—C8—C5—C1	−158.65 (13)	O2—C7—C6—C5	179.24 (12)
C1—C2—C11—O3	1.6 (2)	O8—C15—O7—C16	−0.3 (2)
C1—C2—C11—O4	−177.43 (13)	C6—C15—O7—C16	179.91 (12)
C3—C2—C11—O3	176.19 (12)	C7—C6—C5—C10	−108.96 (13)
C3—C2—C11—O4	−2.9 (2)	C15—C6—C5—C10	68.20 (17)
C5—C6—C15—O7	2.9 (2)	C15—C6—C5—C4	−58.08 (17)
C5—C6—C15—O8	−176.92 (13)	C7—C6—C5—C1	13.07 (14)
C7—C6—C15—O7	179.87 (12)	C15—C6—C5—C1	−169.77 (13)
C7—C6—C15—O8	0.1 (2)	C2—C1—C5—C6	95.62 (11)
C9—C1—C5—C10	−25.72 (16)	C9—C1—C5—C6	−145.41 (11)
O1—C3—C2—C11	2.0 (2)	C8—C1—C5—C6	−20.06 (12)
O1—C3—C2—C1	177.41 (13)	C2—C1—C5—C10	−144.69 (11)
C4—C3—C2—C11	−177.87 (11)	C8—C1—C5—C10	99.63 (13)
O4—C11—O3—C12	0.09 (19)	C2—C1—C5—C4	−19.62 (12)
C2—C11—O3—C12	−178.95 (11)	C9—C1—C5—C4	99.35 (13)
C3—C2—C1—C9	−107.78 (13)	C8—C1—C5—C4	−135.30 (10)
C11—C2—C1—C9	67.13 (17)	O1—C3—C4—C13	−69.49 (16)
C3—C2—C1—C8	125.71 (12)	C2—C3—C4—C13	110.40 (14)
C11—C2—C1—C8	−59.39 (17)	O1—C3—C4—C5	169.50 (12)
C3—C2—C1—C5	14.07 (14)	C10—C5—C4—C3	144.29 (11)
C11—C2—C1—C5	−171.02 (12)	C6—C5—C4—C13	149.43 (11)
C2—C1—C8—C7	−89.09 (12)	C10—C5—C4—C13	24.31 (15)
C9—C1—C8—C7	146.10 (11)	C1—C5—C4—C13	−101.55 (12)
C2—C1—C8—C17	148.74 (11)	C3—C4—C13—O10	−34.2 (2)
C9—C1—C8—C17	23.92 (15)	C5—C4—C13—O10	80.53 (17)
C5—C1—C8—C17	−102.08 (12)	C3—C4—C13—O9	148.10 (12)
C7—C8—C17—O6	147.02 (14)	C5—C4—C13—O9	−97.19 (13)
C1—C8—C17—O6	−97.04 (16)	O10—C13—O9—C14	−0.4 (2)
C7—C8—C17—O5	−35.28 (16)	C4—C13—O9—C14	177.32 (12)
C1—C8—C17—O5	80.66 (14)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···O4	0.89 (2)	1.85 (2)	2.6354 (16)	146 (2)
O2—H2···O8	0.89 (2)	1.86 (2)	2.6533 (15)	146.8 (18)
C4—H4···O1^i	0.98	2.56	3.2533 (18)	128

Symmetry code: (i) −x+1, −y, −z+1.

(III) tetramethyl cis,cis-3,7-dimethoxybicyclo[3.3.0]octa-2,6-diene- 2,4-exo,6,8-exo-tetracarboxylate

Crystal data

C18H22O10	F(000) = 840
Mr = 398.36	Dx = 1.444 Mg m^−3
Monoclinic, P21/n	Melting point = 138.7–140 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 13.4118 (4) Å	Cell parameters from 5768 reflections
b = 8.3693 (3) Å	θ = 2.4–25.0°
c = 17.4894 (6) Å	µ = 0.12 mm^−1
β = 111.049 (1)°	T = 150 K
V = 1832.15 (11) Å^3	Plate, colorless
Z = 4	0.48 × 0.43 × 0.42 mm

Data collection

Siemens SMART CCD area-detector diffractometer	3200 independent reflections
Radiation source: fine-focus sealed tube	2987 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.011
ϕ and ω scans	θmax = 25.0°, θmin = 2.4°
Absorption correction: part of the refinement model (ΔF) (SADABS; Bruker, 1999)	h = −12→15
Tmin = 0.923, Tmax = 0.930	k = −9→8
8916 measured reflections	l = −20→20

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.095	H-atom parameters constrained
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0586P)^2 + 0.5767P] where P = (Fo^2 + 2Fc^2)/3
3200 reflections	(Δ/σ)max = 0.001
259 parameters	Δρmax = 0.23 e Å^−3
0 restraints	Δρmin = −0.22 e Å^−3

Special details

Experimental. 0.3 ° between frames and 5 secs exposure (per frame)

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

5.0507 (0.0076) x + 6.9880 (0.0028) y + 4.1842 (0.0104) z = 8.4589 (0.0077)

* -0.0739 (0.0007) C1 * 0.0265 (0.0008) C2 * 0.0331 (0.0008) C3 * -0.0767 (0.0008) C4 * 0.0909 (0.0008) C5

Rms deviation of fitted atoms = 0.0654

2.8683 (0.0079) x - 7.1206 (0.0027) y + 6.4915 (0.0098) z = 7.1480 (0.0092)

Angle to previous plane (with approximate e.s.d.) = 64.07 (0.04)

* -0.0883 (0.0007) C1 * 0.0654 (0.0007) C5 * -0.0139 (0.0008) C6 * -0.0447 (0.0008) C7 * 0.0814 (0.0007) C8

Rms deviation of fitted atoms = 0.0646

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.52621 (7)	0.37842 (11)	0.78155 (5)	0.0273 (2)
C3	0.58527 (10)	0.28676 (14)	0.84417 (7)	0.0207 (3)
C2	0.56213 (10)	0.26186 (14)	0.91209 (7)	0.0200 (3)
C1	0.64240 (10)	0.15354 (15)	0.97211 (7)	0.0200 (3)
H1	0.6098	0.0479	0.9762	0.024*
C8	0.69694 (10)	0.23027 (15)	1.05832 (7)	0.0206 (3)
H8	0.6536	0.3220	1.0659	0.025*
C7	0.80264 (9)	0.28838 (15)	1.05593 (7)	0.0201 (3)
C6	0.82297 (10)	0.23274 (15)	0.99065 (7)	0.0204 (3)
C5	0.73180 (10)	0.13450 (15)	0.93539 (7)	0.0201 (3)
H5	0.7533	0.0199	0.9362	0.024*
C4	0.68487 (10)	0.19815 (15)	0.84569 (7)	0.0212 (3)
H4	0.7362	0.2739	0.8352	0.025*
O2	0.86934 (7)	0.38144 (11)	1.11422 (5)	0.0258 (2)
C11	0.46832 (10)	0.32464 (15)	0.92628 (7)	0.0218 (3)
C12	0.36928 (11)	0.30590 (17)	1.01419 (9)	0.0311 (3)
H12A	0.3868	0.4143	1.0361	0.047*
H12B	0.3617	0.2358	1.0566	0.047*
H12C	0.3020	0.3078	0.9670	0.047*
C17	0.71197 (10)	0.10518 (16)	1.12471 (7)	0.0234 (3)
C18	0.80666 (12)	−0.12839 (17)	1.18459 (9)	0.0331 (3)
H18A	0.8405	−0.0815	1.2392	0.050*
H18B	0.8549	−0.2072	1.1750	0.050*
H18C	0.7398	−0.1809	1.1811	0.050*
C15	0.92350 (10)	0.23535 (16)	0.97540 (7)	0.0225 (3)
C16	1.10344 (11)	0.31702 (19)	1.02083 (9)	0.0336 (3)
H16A	1.1240	0.2061	1.0162	0.050*
H16B	1.1573	0.3673	1.0684	0.050*
H16C	1.0984	0.3758	0.9711	0.050*
C13	0.66100 (10)	0.05941 (16)	0.78566 (7)	0.0240 (3)
C14	0.58366 (13)	−0.19767 (19)	0.75791 (10)	0.0412 (4)
H14A	0.5496	−0.1722	0.6996	0.062*
H14B	0.5368	−0.2679	0.7747	0.062*
H14C	0.6519	−0.2518	0.7673	0.062*
C19	0.55477 (11)	0.39131 (17)	0.70966 (8)	0.0274 (3)
H19A	0.6280	0.4318	0.7254	0.041*
H19B	0.5056	0.4651	0.6705	0.041*
H19C	0.5501	0.2858	0.6843	0.041*
C20	0.84494 (11)	0.41427 (17)	1.18655 (8)	0.0273 (3)
H20A	0.7735	0.4615	1.1706	0.041*
H20B	0.8978	0.4891	1.2218	0.041*
H20C	0.8470	0.3145	1.2164	0.041*
O3	0.45349 (7)	0.24690 (11)	0.98900 (6)	0.0267 (2)
O4	0.41053 (8)	0.43152 (12)	0.88894 (6)	0.0325 (2)
O9	0.78408 (7)	−0.00385 (11)	1.12332 (6)	0.0284 (2)
O10	0.66433 (9)	0.10221 (13)	1.17097 (6)	0.0394 (3)
O7	1.00120 (7)	0.31978 (12)	1.03082 (5)	0.0273 (2)
O8	0.93557 (7)	0.16363 (12)	0.91925 (6)	0.0315 (2)
O5	0.60255 (8)	−0.05148 (12)	0.80537 (6)	0.0308 (2)
O6	0.69332 (8)	0.04627 (13)	0.73003 (6)	0.0334 (2)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0286 (5)	0.0331 (5)	0.0216 (5)	0.0084 (4)	0.0108 (4)	0.0082 (4)
C3	0.0206 (6)	0.0195 (6)	0.0210 (6)	−0.0003 (5)	0.0060 (5)	−0.0004 (5)
C2	0.0200 (6)	0.0191 (6)	0.0209 (6)	−0.0004 (5)	0.0073 (5)	−0.0003 (5)
C1	0.0203 (6)	0.0203 (6)	0.0204 (6)	0.0008 (5)	0.0084 (5)	0.0007 (5)
C8	0.0213 (6)	0.0224 (6)	0.0194 (6)	0.0023 (5)	0.0089 (5)	0.0010 (5)
C7	0.0213 (6)	0.0203 (6)	0.0184 (6)	0.0018 (5)	0.0068 (5)	0.0020 (5)
C6	0.0204 (6)	0.0215 (6)	0.0193 (6)	0.0018 (5)	0.0070 (5)	0.0015 (5)
C5	0.0208 (6)	0.0207 (6)	0.0192 (6)	0.0021 (5)	0.0078 (5)	0.0000 (5)
C4	0.0206 (6)	0.0247 (6)	0.0188 (6)	0.0005 (5)	0.0077 (5)	−0.0006 (5)
O2	0.0259 (5)	0.0316 (5)	0.0221 (5)	−0.0053 (4)	0.0113 (4)	−0.0074 (4)
C11	0.0204 (6)	0.0223 (6)	0.0217 (6)	−0.0014 (5)	0.0064 (5)	−0.0018 (5)
C12	0.0324 (7)	0.0324 (7)	0.0374 (8)	−0.0007 (6)	0.0232 (6)	−0.0031 (6)
C17	0.0231 (6)	0.0274 (7)	0.0201 (6)	−0.0006 (5)	0.0081 (5)	0.0007 (5)
C18	0.0343 (8)	0.0297 (7)	0.0330 (7)	0.0039 (6)	0.0094 (6)	0.0112 (6)
C15	0.0231 (6)	0.0253 (7)	0.0191 (6)	0.0036 (5)	0.0076 (5)	0.0030 (5)
C16	0.0215 (7)	0.0449 (9)	0.0372 (8)	−0.0014 (6)	0.0138 (6)	0.0002 (7)
C13	0.0197 (6)	0.0308 (7)	0.0199 (6)	0.0055 (5)	0.0050 (5)	−0.0005 (5)
C14	0.0389 (8)	0.0361 (8)	0.0472 (9)	−0.0077 (7)	0.0139 (7)	−0.0196 (7)
C19	0.0291 (7)	0.0327 (7)	0.0214 (6)	0.0003 (6)	0.0102 (5)	0.0051 (5)
C20	0.0273 (7)	0.0349 (7)	0.0201 (6)	0.0009 (6)	0.0091 (5)	−0.0069 (5)
O3	0.0266 (5)	0.0283 (5)	0.0305 (5)	0.0031 (4)	0.0167 (4)	0.0032 (4)
O4	0.0298 (5)	0.0354 (6)	0.0349 (5)	0.0125 (4)	0.0146 (4)	0.0096 (4)
O9	0.0301 (5)	0.0280 (5)	0.0292 (5)	0.0061 (4)	0.0131 (4)	0.0092 (4)
O10	0.0474 (6)	0.0452 (6)	0.0367 (6)	0.0101 (5)	0.0285 (5)	0.0138 (5)
O7	0.0208 (5)	0.0365 (5)	0.0263 (5)	−0.0032 (4)	0.0107 (4)	−0.0032 (4)
O8	0.0271 (5)	0.0439 (6)	0.0262 (5)	0.0027 (4)	0.0129 (4)	−0.0070 (4)
O5	0.0311 (5)	0.0307 (5)	0.0320 (5)	−0.0063 (4)	0.0132 (4)	−0.0106 (4)
O6	0.0371 (5)	0.0411 (6)	0.0259 (5)	0.0037 (4)	0.0162 (4)	−0.0052 (4)

Geometric parameters (Å, º)

C1—C2	1.5069 (17)	C12—H12C	0.9800
C1—C8	1.5584 (17)	C17—O10	1.1978 (16)
C1—C5	1.5583 (17)	C17—O9	1.3362 (16)
C2—C3	1.3476 (17)	C18—O9	1.4469 (16)
C3—C4	1.5197 (17)	C18—H18A	0.9800
C4—C5	1.5595 (16)	C18—H18B	0.9800
C5—C6	1.5021 (17)	C18—H18C	0.9800
C6—C7	1.3485 (17)	C15—O8	1.2105 (16)
C7—C8	1.5134 (17)	C15—O7	1.3413 (16)
O1—C3	1.3387 (15)	C16—O7	1.4433 (15)
O1—C19	1.4439 (15)	C16—H16A	0.9800
C2—C11	1.4646 (17)	C16—H16B	0.9800
C1—H1	1.0000	C16—H16C	0.9800
C8—C17	1.5222 (17)	C13—O6	1.2040 (16)
C8—H8	1.0000	C13—O5	1.3375 (17)
C7—O2	1.3383 (15)	C14—O5	1.4489 (17)
C6—C15	1.4655 (17)	C14—H14A	0.9800
C5—H5	1.0000	C14—H14B	0.9800
C4—C13	1.5204 (17)	C14—H14C	0.9800
C4—H4	1.0000	C19—H19A	0.9800
O2—C20	1.4423 (15)	C19—H19B	0.9800
C11—O4	1.2099 (15)	C19—H19C	0.9800
C11—O3	1.3501 (16)	C20—H20A	0.9800
C12—O3	1.4390 (15)	C20—H20B	0.9800
C12—H12A	0.9800	C20—H20C	0.9800
C12—H12B	0.9800	O1—O2	5.983 (1)
C3—O1—C19	119.41 (10)	H12A—C12—H12C	109.5
C7—O2—C20	118.61 (10)	H12B—C12—H12C	109.5
O1—C3—C2	123.63 (11)	O10—C17—O9	124.29 (12)
O1—C3—C4	123.51 (11)	O10—C17—C8	124.95 (12)
C2—C3—C4	112.85 (11)	O9—C17—C8	110.75 (10)
C3—C2—C11	125.29 (11)	O9—C18—H18A	109.5
C3—C2—C1	111.96 (11)	O9—C18—H18B	109.5
C11—C2—C1	122.69 (10)	H18A—C18—H18B	109.5
C2—C1—C8	113.31 (10)	O9—C18—H18C	109.5
C2—C1—C5	103.74 (9)	H18A—C18—H18C	109.5
C8—C1—C5	106.12 (9)	H18B—C18—H18C	109.5
C2—C1—H1	111.1	O8—C15—O7	123.50 (11)
C8—C1—H1	111.1	O8—C15—C6	122.69 (12)
C5—C1—H1	111.1	O7—C15—C6	113.78 (10)
C7—C8—C17	111.92 (10)	O7—C16—H16A	109.5
C7—C8—C1	102.97 (9)	O7—C16—H16B	109.5
C17—C8—C1	110.01 (10)	H16A—C16—H16B	109.5
C7—C8—H8	110.6	O7—C16—H16C	109.5
C17—C8—H8	110.6	H16A—C16—H16C	109.5
C1—C8—H8	110.6	H16B—C16—H16C	109.5
O2—C7—C6	124.25 (11)	O6—C13—O5	124.02 (12)
O2—C7—C8	122.85 (10)	O6—C13—C4	125.46 (12)
C6—C7—C8	112.87 (11)	O5—C13—C4	110.45 (10)
C7—C6—C15	128.90 (12)	O5—C14—H14A	109.5
C7—C6—C5	111.61 (11)	O5—C14—H14B	109.5
C15—C6—C5	118.73 (11)	H14A—C14—H14B	109.5
C6—C5—C1	104.35 (10)	O5—C14—H14C	109.5
C6—C5—C4	113.67 (10)	H14A—C14—H14C	109.5
C1—C5—C4	106.70 (9)	H14B—C14—H14C	109.5
C6—C5—H5	110.6	O1—C19—H19A	109.5
C1—C5—H5	110.6	O1—C19—H19B	109.5
C4—C5—H5	110.6	H19A—C19—H19B	109.5
C3—C4—C13	113.26 (10)	O1—C19—H19C	109.5
C3—C4—C5	102.65 (9)	H19A—C19—H19C	109.5
C13—C4—C5	110.04 (10)	H19B—C19—H19C	109.5
C3—C4—H4	110.2	O2—C20—H20A	109.5
C13—C4—H4	110.2	O2—C20—H20B	109.5
C5—C4—H4	110.2	H20A—C20—H20B	109.5
O4—C11—O3	122.83 (12)	O2—C20—H20C	109.5
O4—C11—C2	126.63 (12)	H20A—C20—H20C	109.5
O3—C11—C2	110.55 (10)	H20B—C20—H20C	109.5
O3—C12—H12A	109.5	C11—O3—C12	116.37 (10)
O3—C12—H12B	109.5	C17—O9—C18	116.03 (10)
H12A—C12—H12B	109.5	C15—O7—C16	115.43 (10)
O3—C12—H12C	109.5	C13—O5—C14	115.87 (11)
C1—C2—C3—C4	0.61 (15)	C17—C8—C7—C6	107.12 (12)
C2—C3—C4—C5	−9.33 (14)	O2—C7—C6—C15	11.5 (2)
C3—C4—C5—C6	−100.54 (11)	C8—C7—C6—C15	−166.71 (12)
C3—C4—C5—C1	13.92 (12)	O2—C7—C6—C5	−178.82 (11)
C4—C5—C6—C7	122.27 (11)	C7—C6—C5—C1	6.42 (13)
C5—C6—C7—C8	3.01 (15)	C15—C6—C5—C1	177.30 (10)
C6—C7—C8—C1	−11.00 (13)	C15—C6—C5—C4	−66.85 (14)
C7—C8—C1—C5	14.14 (12)	C2—C1—C5—C6	106.85 (11)
C4—C3—O1—C19	2.28 (17)	C8—C1—C5—C6	−12.79 (12)
C8—C7—O2—C20	6.61 (17)	C2—C1—C5—C4	−13.77 (12)
C1—C2—C11—O4	166.75 (12)	C8—C1—C5—C4	−133.41 (10)
C1—C2—C11—O3	−12.78 (16)	O1—C3—C4—C13	−70.06 (15)
C3—C2—C11—O3	164.30 (12)	C2—C3—C4—C13	109.27 (12)
C3—C2—C11—O4	−16.2 (2)	O1—C3—C4—C5	171.34 (11)
C5—C6—C15—O7	−176.66 (10)	C6—C5—C4—C13	138.62 (11)
C5—C6—C15—O8	1.25 (19)	C1—C5—C4—C13	−106.92 (11)
C7—C6—C15—O7	−7.57 (19)	C7—C8—C17—O10	135.64 (14)
C7—C6—C15—O8	170.33 (13)	C1—C8—C17—O10	−110.53 (14)
C2—C3—O1—C19	−176.97 (12)	C7—C8—C17—O9	−45.82 (14)
C6—C7—O2—C20	−171.39 (12)	C1—C8—C17—O9	68.01 (13)
O1—C3—C2—C11	2.6 (2)	C3—C4—C13—O6	119.69 (13)
C4—C3—C2—C11	−176.74 (11)	C5—C4—C13—O6	−126.07 (13)
O1—C3—C2—C1	179.94 (11)	C3—C4—C13—O5	−63.23 (14)
C3—C2—C1—C8	123.06 (11)	C5—C4—C13—O5	51.00 (13)
C11—C2—C1—C8	−59.51 (15)	O4—C11—O3—C12	−4.72 (18)
C3—C2—C1—C5	8.45 (14)	C2—C11—O3—C12	174.83 (10)
C11—C2—C1—C5	−174.12 (11)	O10—C17—O9—C18	−2.33 (19)
C2—C1—C8—C7	−99.04 (11)	C8—C17—O9—C18	179.12 (11)
C2—C1—C8—C17	141.51 (10)	O8—C15—O7—C16	−1.57 (18)
C5—C1—C8—C17	−105.30 (11)	C6—C15—O7—C16	176.31 (11)
C17—C8—C7—O2	−71.09 (15)	O6—C13—O5—C14	3.27 (18)
C1—C8—C7—O2	170.79 (10)	C4—C13—O5—C14	−173.85 (11)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8···O4^i	1.00	2.47	3.4489 (15)	166

Symmetry code: (i) −x+1, −y+1, −z+2.

(IV) tetramethyl cis,cis-3,7-dimethoxy-1,5-dimethylbicyclo[3.3.0]octa-2,6-diene- 2,4-exo,6,8-exo-tetracarboxylate

Crystal data

C20H26O10	F(000) = 904
Mr = 426.41	Dx = 1.391 Mg m^−3
Monoclinic, P21/n	Melting point = 167.5–169.1 K
Hall symbol: -P 2yn	Mo Kα radiation, λ = 0.71073 Å
a = 11.6352 (4) Å	Cell parameters from 4847 reflections
b = 13.3095 (4) Å	θ = 2.2–24.9°
c = 13.2262 (4) Å	µ = 0.11 mm^−1
β = 96.369 (1)°	T = 150 K
V = 2035.55 (11) Å^3	Paralellepiped, colorless
Z = 4	0.60 × 0.29 × 0.14 mm

Data collection

Siemens SMART CCD area-detector diffractometer	3594 independent reflections
Radiation source: fine-focus sealed tube	3089 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
ϕ and ω scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: part of the refinement model (ΔF) (SADABS; Bruker, 1999)	h = −13→13
Tmin = 0.936, Tmax = 0.985	k = −15→15
12490 measured reflections	l = −15→15

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.040	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.112	H-atom parameters constrained
S = 1.01	w = 1/[σ^2(Fo^2) + (0.0702P)^2 + 0.5233P] where P = (Fo^2 + 2Fc^2)/3
3594 reflections	(Δ/σ)max < 0.001
279 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.18 e Å^−3

Special details

Experimental. 0.3 ° between frames and ten second by frame

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 6.9178 (0.0060) x + 9.9782 (0.0047) y + 4.6920 (0.0078) z = 1.9998 (0.0032)

* 0.0752 (0.0009) C5 * -0.0428 (0.0010) C6 * -0.0567 (0.0010) C7 * 0.0849 (0.0009) C8 * -0.0606 (0.0006) C9

Rms deviation of fitted atoms = 0.0657

6.8819 (0.0068) x + 10.2854 (0.0061) y - 3.8927 (0.0092) z = 1.3324 (0.0034)

Angle to previous plane (with approximate e.s.d.) = 80.74 (0.04)

* -0.1163 (0.0009) C1 * 0.0505 (0.0009) C2 * 0.0404 (0.0009) C3 * -0.1117 (0.0009) C4 * 0.1371 (0.0009) C5

Rms deviation of fitted atoms = 0.0990

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 (Ų)

	x	y	z	Uiso*/Ueq
C1	0.11773 (12)	0.17048 (11)	0.34618 (11)	0.0208 (3)
C9	0.09502 (14)	0.07178 (12)	0.40074 (12)	0.0269 (4)
H9A	0.1113	0.0812	0.4744	0.040*
H9B	0.1453	0.0190	0.3785	0.040*
H9C	0.0139	0.0522	0.3841	0.040*
C2	0.03514 (12)	0.25226 (11)	0.37341 (11)	0.0203 (3)
C11	0.03992 (12)	0.28833 (11)	0.47906 (11)	0.0228 (3)
O3	−0.04106 (10)	0.35730 (9)	0.49344 (8)	0.0294 (3)
O4	0.10901 (10)	0.25862 (10)	0.54745 (8)	0.0353 (3)
C12	−0.04631 (15)	0.38749 (14)	0.59769 (12)	0.0338 (4)
H12A	−0.0396	0.3281	0.6417	0.051*
H12B	−0.1203	0.4210	0.6036	0.051*
H12C	0.0173	0.4339	0.6185	0.051*
C3	−0.04447 (12)	0.27484 (11)	0.29494 (11)	0.0195 (3)
O1	−0.12785 (9)	0.34373 (8)	0.29795 (8)	0.0243 (3)
C19	−0.22187 (14)	0.34648 (13)	0.21715 (12)	0.0303 (4)
H19A	−0.1907	0.3457	0.1513	0.045*
H19B	−0.2672	0.4079	0.2230	0.045*
H19C	−0.2716	0.2877	0.2223	0.045*
C4	−0.02964 (12)	0.21438 (11)	0.20048 (11)	0.0199 (3)
H4	−0.0303	0.2597	0.1401	0.024*
C13	−0.12315 (13)	0.13469 (11)	0.18155 (11)	0.0229 (3)
O5	−0.14560 (9)	0.11484 (8)	0.08236 (8)	0.0271 (3)
O6	−0.16929 (10)	0.09271 (9)	0.24686 (8)	0.0333 (3)
C14	−0.22564 (15)	0.03314 (14)	0.05613 (13)	0.0354 (4)
H14A	−0.1869	−0.0311	0.0727	0.053*
H14B	−0.2518	0.0355	−0.0169	0.053*
H14C	−0.2924	0.0397	0.0948	0.053*
C5	0.09320 (12)	0.16616 (11)	0.22630 (11)	0.0201 (3)
C10	0.10202 (14)	0.06080 (12)	0.18091 (12)	0.0263 (4)
H10A	0.0855	0.0644	0.1067	0.039*
H10B	0.0459	0.0162	0.2082	0.039*
H10C	0.1803	0.0345	0.1988	0.039*
C6	0.18625 (12)	0.23470 (11)	0.19259 (11)	0.0200 (3)
C15	0.18578 (12)	0.26095 (11)	0.08470 (11)	0.0219 (3)
O7	0.26643 (9)	0.32846 (8)	0.06696 (8)	0.0269 (3)
O8	0.11922 (10)	0.22563 (10)	0.01750 (8)	0.0370 (3)
C16	0.27092 (15)	0.35358 (13)	−0.03885 (11)	0.0308 (4)
H16A	0.2741	0.2917	−0.0786	0.046*
H16B	0.3400	0.3941	−0.0456	0.046*
H16C	0.2017	0.3919	−0.0641	0.046*
C7	0.26911 (12)	0.25479 (11)	0.26904 (11)	0.0200 (3)
O2	0.36325 (9)	0.31099 (8)	0.25969 (8)	0.0261 (3)
C20	0.45815 (14)	0.30572 (13)	0.33904 (13)	0.0300 (4)
H20A	0.4311	0.3242	0.4041	0.045*
H20B	0.5192	0.3522	0.3237	0.045*
H20C	0.4888	0.2371	0.3434	0.045*
C8	0.24663 (12)	0.20688 (11)	0.36799 (11)	0.0216 (3)
H8	0.2517	0.2594	0.4223	0.026*
C17	0.33117 (13)	0.12264 (12)	0.40054 (11)	0.0241 (3)
O9	0.36350 (9)	0.07278 (8)	0.32022 (8)	0.0264 (3)
O10	0.36554 (10)	0.10318 (10)	0.48696 (8)	0.0373 (3)
C18	0.44581 (15)	−0.00747 (13)	0.34336 (14)	0.0340 (4)
H18A	0.5210	0.0210	0.3694	0.051*
H18B	0.4538	−0.0462	0.2815	0.051*
H18C	0.4185	−0.0517	0.3949	0.051*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0224 (8)	0.0214 (8)	0.0186 (8)	0.0026 (6)	0.0018 (6)	0.0012 (6)
C9	0.0310 (9)	0.0257 (8)	0.0248 (8)	0.0033 (7)	0.0060 (7)	0.0056 (6)
C2	0.0214 (7)	0.0210 (7)	0.0187 (8)	−0.0003 (6)	0.0034 (6)	0.0009 (6)
C11	0.0210 (8)	0.0256 (8)	0.0223 (8)	0.0006 (6)	0.0041 (6)	0.0002 (6)
O3	0.0342 (6)	0.0347 (6)	0.0191 (6)	0.0114 (5)	0.0016 (5)	−0.0040 (5)
O4	0.0337 (7)	0.0529 (8)	0.0181 (6)	0.0147 (6)	−0.0031 (5)	−0.0035 (5)
C12	0.0350 (9)	0.0454 (10)	0.0212 (8)	0.0076 (8)	0.0045 (7)	−0.0086 (7)
C3	0.0196 (7)	0.0192 (7)	0.0203 (8)	−0.0012 (6)	0.0045 (6)	0.0007 (6)
O1	0.0227 (5)	0.0276 (6)	0.0217 (6)	0.0070 (4)	−0.0013 (4)	−0.0029 (4)
C19	0.0248 (8)	0.0391 (10)	0.0256 (9)	0.0080 (7)	−0.0025 (6)	−0.0023 (7)
C4	0.0192 (7)	0.0228 (8)	0.0179 (7)	−0.0004 (6)	0.0032 (6)	0.0006 (6)
C13	0.0210 (7)	0.0261 (8)	0.0217 (8)	0.0010 (6)	0.0026 (6)	−0.0034 (6)
O5	0.0245 (6)	0.0337 (6)	0.0225 (6)	−0.0060 (5)	0.0005 (4)	−0.0064 (5)
O6	0.0375 (7)	0.0365 (7)	0.0269 (6)	−0.0134 (5)	0.0084 (5)	−0.0029 (5)
C14	0.0309 (9)	0.0383 (10)	0.0360 (10)	−0.0094 (8)	−0.0005 (7)	−0.0135 (8)
C5	0.0213 (7)	0.0218 (8)	0.0173 (7)	0.0010 (6)	0.0021 (6)	−0.0002 (6)
C10	0.0276 (8)	0.0241 (8)	0.0272 (8)	0.0010 (6)	0.0034 (6)	−0.0047 (6)
C6	0.0194 (7)	0.0208 (7)	0.0199 (8)	0.0032 (6)	0.0028 (6)	−0.0004 (6)
C15	0.0175 (7)	0.0269 (8)	0.0213 (8)	0.0029 (6)	0.0020 (6)	−0.0007 (6)
O7	0.0303 (6)	0.0326 (6)	0.0183 (5)	−0.0064 (5)	0.0047 (4)	0.0030 (4)
O8	0.0310 (6)	0.0594 (8)	0.0194 (6)	−0.0145 (6)	−0.0027 (5)	0.0021 (5)
C16	0.0366 (9)	0.0379 (10)	0.0189 (8)	−0.0011 (8)	0.0073 (7)	0.0045 (7)
C7	0.0188 (7)	0.0198 (8)	0.0212 (8)	0.0029 (6)	0.0021 (6)	−0.0008 (6)
O2	0.0211 (5)	0.0306 (6)	0.0252 (6)	−0.0047 (5)	−0.0041 (4)	0.0041 (5)
C20	0.0238 (8)	0.0309 (9)	0.0330 (9)	−0.0012 (7)	−0.0067 (7)	0.0014 (7)
C8	0.0216 (8)	0.0236 (8)	0.0194 (7)	0.0041 (6)	0.0012 (6)	0.0006 (6)
C17	0.0214 (8)	0.0287 (8)	0.0221 (8)	0.0020 (6)	0.0023 (6)	0.0026 (6)
O9	0.0283 (6)	0.0263 (6)	0.0242 (6)	0.0092 (5)	0.0015 (4)	0.0013 (4)
O10	0.0393 (7)	0.0507 (8)	0.0214 (6)	0.0178 (6)	0.0008 (5)	0.0077 (5)
C18	0.0327 (9)	0.0278 (9)	0.0416 (10)	0.0124 (7)	0.0039 (7)	0.0031 (7)

Geometric parameters (Å, º)

C1—C2	1.521 (2)	O5—C14	1.4485 (19)
C1—C8	1.572 (2)	C14—H14A	0.9800
C1—C5	1.581 (2)	C14—H14B	0.9800
C2—C3	1.346 (2)	C14—H14C	0.9800
C3—C4	1.512 (2)	C5—C10	1.533 (2)
C4—C5	1.569 (2)	C10—H10A	0.9800
C5—C6	1.520 (2)	C10—H10B	0.9800
C6—C7	1.344 (2)	C10—H10C	0.9800
C7—C8	1.505 (2)	C6—C15	1.469 (2)
C1—C9	1.536 (2)	C15—O8	1.2075 (19)
C9—H9A	0.9800	C15—O7	1.3385 (18)
C9—H9B	0.9800	O7—C16	1.4453 (18)
C9—H9C	0.9800	C16—H16A	0.9800
C2—C11	1.473 (2)	C16—H16B	0.9800
C11—O4	1.2081 (18)	C16—H16C	0.9800
C11—O3	1.3440 (18)	C7—O2	1.3434 (18)
O3—C12	1.4440 (18)	O2—C20	1.4382 (19)
C12—H12A	0.9800	C20—H20A	0.9800
C12—H12B	0.9800	C20—H20B	0.9800
C12—H12C	0.9800	C20—H20C	0.9800
C3—O1	1.3386 (18)	C8—C17	1.522 (2)
O1—C19	1.4425 (18)	C8—H8	1.0000
C19—H19A	0.9800	C17—O10	1.1967 (18)
C19—H19B	0.9800	C17—O9	1.3413 (18)
C19—H19C	0.9800	O9—C18	1.4446 (18)
C4—C13	1.520 (2)	C18—H18A	0.9800
C4—H4	1.0000	C18—H18B	0.9800
C13—O6	1.2039 (19)	C18—H18C	0.9800
C13—O5	1.3353 (18)	O1—O2	5.808 (2)
C3—O1—C19	119.20 (11)	H14B—C14—H14C	109.5
C7—O2—C20	118.26 (12)	C6—C5—C10	110.69 (12)
C2—C1—C9	110.77 (12)	C6—C5—C4	110.60 (11)
C2—C1—C8	110.54 (12)	C10—C5—C4	112.81 (12)
C9—C1—C8	112.81 (12)	C6—C5—C1	102.55 (11)
C2—C1—C5	102.42 (11)	C10—C5—C1	114.43 (12)
C9—C1—C5	114.76 (12)	C4—C5—C1	105.19 (11)
C8—C1—C5	104.93 (11)	C5—C10—H10A	109.5
C1—C9—H9A	109.5	C5—C10—H10B	109.5
C1—C9—H9B	109.5	H10A—C10—H10B	109.5
H9A—C9—H9B	109.5	C5—C10—H10C	109.5
C1—C9—H9C	109.5	H10A—C10—H10C	109.5
H9A—C9—H9C	109.5	H10B—C10—H10C	109.5
H9B—C9—H9C	109.5	C7—C6—C15	127.49 (14)
C3—C2—C11	127.52 (13)	C7—C6—C5	111.93 (13)
C3—C2—C1	112.08 (12)	C15—C6—C5	120.13 (12)
C11—C2—C1	119.97 (12)	O8—C15—O7	122.49 (14)
O4—C11—O3	122.43 (14)	O8—C15—C6	123.75 (14)
O4—C11—C2	123.76 (14)	O7—C15—C6	113.77 (12)
O3—C11—C2	113.81 (12)	C15—O7—C16	115.24 (12)
C11—O3—C12	115.45 (12)	O7—C16—H16A	109.5
O3—C12—H12A	109.5	O7—C16—H16B	109.5
O3—C12—H12B	109.5	H16A—C16—H16B	109.5
H12A—C12—H12B	109.5	O7—C16—H16C	109.5
O3—C12—H12C	109.5	H16A—C16—H16C	109.5
H12A—C12—H12C	109.5	H16B—C16—H16C	109.5
H12B—C12—H12C	109.5	O2—C7—C6	124.44 (13)
O1—C3—C2	124.68 (13)	O2—C7—C8	122.57 (12)
O1—C3—C4	122.59 (12)	C6—C7—C8	112.99 (13)
C2—C3—C4	112.73 (13)	O2—C20—H20A	109.5
O1—C19—H19A	109.5	O2—C20—H20B	109.5
O1—C19—H19B	109.5	H20A—C20—H20B	109.5
H19A—C19—H19B	109.5	O2—C20—H20C	109.5
O1—C19—H19C	109.5	H20A—C20—H20C	109.5
H19A—C19—H19C	109.5	H20B—C20—H20C	109.5
H19B—C19—H19C	109.5	C7—C8—C17	112.90 (12)
C3—C4—C13	111.24 (12)	C7—C8—C1	103.03 (11)
C3—C4—C5	102.86 (11)	C17—C8—C1	113.48 (12)
C13—C4—C5	111.62 (12)	C7—C8—H8	109.1
C3—C4—H4	110.3	C17—C8—H8	109.1
C13—C4—H4	110.3	C1—C8—H8	109.1
C5—C4—H4	110.3	O10—C17—O9	123.79 (14)
O6—C13—O5	123.97 (14)	O10—C17—C8	124.52 (14)
O6—C13—C4	125.01 (13)	O9—C17—C8	111.69 (12)
O5—C13—C4	111.00 (12)	C17—O9—C18	115.82 (12)
C13—O5—C14	115.75 (12)	O9—C18—H18A	109.5
O5—C14—H14A	109.5	O9—C18—H18B	109.5
O5—C14—H14B	109.5	H18A—C18—H18B	109.5
H14A—C14—H14B	109.5	O9—C18—H18C	109.5
O5—C14—H14C	109.5	H18A—C18—H18C	109.5
H14A—C14—H14C	109.5	H18B—C18—H18C	109.5
C1—C2—C3—C4	−0.89 (17)	O6—C13—O5—C14	−3.8 (2)
C2—C3—C4—C5	−12.71 (16)	C4—C13—O5—C14	174.39 (12)
C3—C4—C5—C6	−89.69 (13)	C13—C4—C5—C6	150.97 (12)
C3—C4—C5—C1	20.35 (14)	C3—C4—C5—C10	145.74 (12)
C4—C5—C6—C7	126.03 (13)	C13—C4—C5—C10	26.39 (17)
C5—C6—C7—C8	−1.57 (17)	C13—C4—C5—C1	−99.00 (13)
C6—C7—C8—C1	−11.98 (16)	C2—C1—C5—C6	94.96 (13)
C7—C8—C1—C5	19.80 (14)	C9—C1—C5—C6	−144.94 (12)
C1—C2—C11—O4	2.1 (2)	C8—C1—C5—C6	−20.54 (14)
C1—C2—C11—O3	−177.17 (12)	C2—C1—C5—C10	−145.13 (12)
C3—C2—C11—O3	−5.4 (2)	C8—C1—C5—C10	99.37 (14)
C3—C2—C11—O4	173.92 (15)	C2—C1—C5—C4	−20.75 (14)
C5—C6—C15—O7	174.57 (12)	C9—C1—C5—C4	99.34 (14)
C5—C6—C15—O8	−5.3 (2)	C8—C1—C5—C4	−136.26 (12)
C7—C6—C15—O7	−13.8 (2)	C10—C5—C6—C7	−108.20 (14)
C7—C6—C15—O8	166.27 (16)	C1—C5—C6—C7	14.28 (15)
C9—C1—C5—C10	−25.03 (18)	C10—C5—C6—C15	64.61 (17)
C2—C3—O1—C19	−167.08 (14)	C4—C5—C6—C15	−61.16 (17)
C4—C3—O1—C19	13.6 (2)	C1—C5—C6—C15	−172.91 (12)
C6—C7—O2—C20	−164.46 (14)	O8—C15—O7—C16	−2.1 (2)
C8—C7—O2—C20	15.1 (2)	C6—C15—O7—C16	178.05 (12)
C9—C1—C2—C3	−108.88 (14)	C15—C6—C7—O2	5.9 (2)
C8—C1—C2—C3	125.31 (13)	C5—C6—C7—O2	178.01 (13)
C5—C1—C2—C3	13.95 (16)	C15—C6—C7—C8	−173.72 (14)
C9—C1—C2—C11	64.11 (17)	O2—C7—C8—C17	−68.77 (18)
C8—C1—C2—C11	−61.70 (17)	C6—C7—C8—C17	110.82 (14)
C5—C1—C2—C11	−173.06 (12)	O2—C7—C8—C1	168.43 (13)
O4—C11—O3—C12	−4.9 (2)	C2—C1—C8—C7	−89.93 (13)
C2—C11—O3—C12	174.36 (13)	C9—C1—C8—C7	145.42 (12)
C11—C2—C3—O1	7.4 (2)	C2—C1—C8—C17	147.66 (12)
C1—C2—C3—O1	179.74 (13)	C9—C1—C8—C17	23.02 (17)
C11—C2—C3—C4	−173.23 (14)	C5—C1—C8—C17	−102.61 (13)
O1—C3—C4—C13	−73.72 (17)	C7—C8—C17—O10	146.12 (16)
C2—C3—C4—C13	106.90 (14)	C1—C8—C17—O10	−97.12 (18)
O1—C3—C4—C5	166.67 (12)	C7—C8—C17—O9	−33.45 (17)
C3—C4—C13—O6	−31.0 (2)	C1—C8—C17—O9	83.31 (15)
C5—C4—C13—O6	83.25 (18)	O10—C17—O9—C18	−0.8 (2)
C3—C4—C13—O5	150.79 (12)	C8—C17—O9—C18	178.74 (12)
C5—C4—C13—O5	−94.96 (14)

(V) tetramethyl cis,cis-3,7-diacetoxybicyclo[3.3.0]octa-2,6-diene- 2,4-exo,6,8-exo-tetracarboxylate

Crystal data

C20H22O12	F(000) = 952
Mr = 454.38	Dx = 1.414 Mg m^−3
Monoclinic, P21/c	Melting point = 96.5–98 K
Hall symbol: -P 2ybc	Mo Kα radiation, λ = 0.71073 Å
a = 10.0095 (5) Å	Cell parameters from 1758 reflections
b = 20.9263 (12) Å	θ = 2.3–20.4°
c = 10.1881 (6) Å	µ = 0.12 mm^−1
β = 90.507 (1)°	T = 150 K
V = 2133.9 (2) Å^3	Needle, colorless
Z = 4	0.34 × 0.12 × 0.12 mm

Data collection

Siemens SMART CCD area-detector diffractometer	3766 independent reflections
Radiation source: fine-focus sealed tube	2596 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.057
ϕ and ω scans	θmax = 25.0°, θmin = 2.0°
Absorption correction: part of the refinement model (ΔF) (SADABS; Bruker, 1999)	h = −11→11
Tmin = 0.983, Tmax = 0.986	k = −24→24
13188 measured reflections	l = −12→12

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.050	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.146	H-atom parameters constrained
S = 0.91	w = 1/[σ^2(Fo^2) + (0.0848P)^2 + 0.784P] where P = (Fo^2 + 2Fc^2)/3
3766 reflections	(Δ/σ)max < 0.001
295 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Experimental. 0.3 ° between frames and 10 secs exposure (per frame)

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.

Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

- 3.1667 (0.0115) x + 9.8588 (0.0222) y - 8.3598 (0.0072) z = 1.1924 (0.0197)

* -0.0830 (0.0015) C1 * 0.0215 (0.0016) C2 * 0.0508 (0.0016) C3 * -0.0987 (0.0015) C4 * 0.1093 (0.0015) C5

Rms deviation of fitted atoms = 0.0795

- 1.7064 (0.0119) x + 10.8406 (0.0211) y + 8.5547 (0.0066) z = 12.7057 (0.0143)

Angle to previous plane (with approximate e.s.d.) = 66.91 (0.07)

* -0.1024 (0.0015) C1 * 0.0771 (0.0015) C5 * -0.0188 (0.0016) C6 * -0.0488 (0.0016) C7 * 0.0930 (0.0015) C8

Rms deviation of fitted atoms = 0.0746

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 (Ų)

	x	y	z	Uiso*/Ueq
O2	0.15575 (18)	0.85543 (8)	0.40805 (16)	0.0306 (5)
C20	0.1299 (3)	0.91663 (13)	0.4463 (3)	0.0312 (6)
C22	0.0648 (3)	0.95339 (14)	0.3381 (3)	0.0414 (7)
H22A	−0.0316	0.9452	0.3382	0.062*
H22B	0.1021	0.9400	0.2538	0.062*
H22C	0.0812	0.9991	0.3511	0.062*
O12	0.1556 (2)	0.93594 (9)	0.5538 (2)	0.0462 (6)
C7	0.2361 (3)	0.81891 (11)	0.4889 (2)	0.0262 (6)
C8	0.1749 (2)	0.76420 (12)	0.5626 (2)	0.0250 (6)
H8	0.1196	0.7370	0.5025	0.030*
C17	0.0911 (3)	0.79030 (12)	0.6735 (3)	0.0277 (6)
O9	−0.03126 (19)	0.80652 (9)	0.62967 (19)	0.0389 (5)
O10	0.1274 (2)	0.79682 (9)	0.78471 (18)	0.0388 (5)
C18	−0.1188 (3)	0.83376 (16)	0.7268 (4)	0.0545 (9)
H18A	−0.1238	0.8050	0.8025	0.082*
H18B	−0.2082	0.8394	0.6886	0.082*
H18C	−0.0836	0.8753	0.7551	0.082*
C1	0.3001 (2)	0.72736 (11)	0.6114 (2)	0.0236 (6)
H1	0.2897	0.7125	0.7040	0.028*
C2	0.3360 (3)	0.67297 (11)	0.5211 (2)	0.0254 (6)
C11	0.2395 (3)	0.62091 (12)	0.4948 (3)	0.0279 (6)
O3	0.28008 (19)	0.58035 (8)	0.40244 (19)	0.0367 (5)
O4	0.13562 (19)	0.61543 (9)	0.55187 (18)	0.0370 (5)
C12	0.1862 (3)	0.53105 (14)	0.3670 (3)	0.0429 (8)
H12A	0.1686	0.5041	0.4437	0.064*
H12B	0.2235	0.5048	0.2966	0.064*
H12C	0.1025	0.5506	0.3367	0.064*
C3	0.4595 (3)	0.67887 (11)	0.4778 (2)	0.0250 (6)
O1	0.52291 (18)	0.63928 (8)	0.38826 (16)	0.0295 (4)
C19	0.5716 (3)	0.58197 (12)	0.4343 (3)	0.0300 (6)
C21	0.6164 (3)	0.54100 (14)	0.3237 (3)	0.0443 (8)
H21A	0.6879	0.5125	0.3544	0.066*
H21B	0.6499	0.5681	0.2527	0.066*
H21C	0.5411	0.5154	0.2913	0.066*
O11	0.5754 (2)	0.56952 (9)	0.54858 (19)	0.0376 (5)
C4	0.5345 (3)	0.73495 (12)	0.5334 (2)	0.0262 (6)
H4	0.5788	0.7600	0.4625	0.031*
C13	0.6356 (3)	0.71023 (12)	0.6318 (3)	0.0306 (6)
O5	0.74851 (19)	0.69360 (9)	0.5718 (2)	0.0413 (5)
O6	0.6175 (2)	0.70481 (10)	0.74725 (18)	0.0425 (5)
C14	0.8453 (3)	0.66068 (15)	0.6540 (4)	0.0552 (9)
H14A	0.8659	0.6869	0.7313	0.083*
H14B	0.9272	0.6533	0.6042	0.083*
H14C	0.8083	0.6196	0.6822	0.083*
C5	0.4211 (2)	0.77394 (11)	0.5975 (2)	0.0248 (6)
H5	0.4496	0.7914	0.6847	0.030*
C6	0.3667 (3)	0.82604 (11)	0.5094 (2)	0.0257 (6)
C15	0.4454 (3)	0.87939 (12)	0.4548 (3)	0.0313 (6)
O7	0.57131 (19)	0.87919 (8)	0.50149 (18)	0.0353 (5)
O8	0.4035 (2)	0.91879 (9)	0.3791 (2)	0.0479 (6)
C16	0.6560 (3)	0.92856 (14)	0.4484 (3)	0.0507 (9)
H16A	0.6528	0.9268	0.3523	0.076*
H16B	0.7481	0.9219	0.4788	0.076*
H16C	0.6246	0.9705	0.4780	0.076*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O2	0.0401 (11)	0.0230 (10)	0.0286 (10)	0.0079 (8)	−0.0044 (8)	0.0009 (8)
C20	0.0315 (16)	0.0314 (15)	0.0308 (15)	0.0058 (12)	0.0038 (12)	0.0022 (12)
C22	0.0485 (19)	0.0337 (16)	0.0418 (17)	0.0103 (14)	−0.0026 (14)	0.0028 (13)
O12	0.0612 (15)	0.0409 (12)	0.0365 (12)	0.0187 (10)	−0.0087 (10)	−0.0100 (9)
C7	0.0365 (16)	0.0209 (13)	0.0212 (13)	0.0062 (11)	−0.0009 (11)	−0.0016 (10)
C8	0.0278 (14)	0.0234 (13)	0.0237 (13)	0.0010 (11)	−0.0012 (11)	−0.0027 (10)
C17	0.0328 (16)	0.0211 (13)	0.0293 (15)	0.0000 (11)	0.0037 (12)	0.0009 (11)
O9	0.0292 (11)	0.0416 (12)	0.0458 (12)	0.0068 (9)	0.0004 (9)	−0.0102 (9)
O10	0.0465 (13)	0.0443 (13)	0.0256 (10)	0.0078 (9)	0.0022 (9)	−0.0041 (9)
C18	0.0367 (19)	0.053 (2)	0.074 (2)	0.0098 (15)	0.0127 (17)	−0.0180 (18)
C1	0.0293 (14)	0.0221 (13)	0.0195 (12)	0.0015 (11)	0.0012 (10)	0.0019 (10)
C2	0.0293 (15)	0.0230 (14)	0.0240 (13)	0.0041 (11)	−0.0018 (11)	0.0018 (10)
C11	0.0309 (15)	0.0228 (13)	0.0299 (14)	0.0067 (11)	−0.0028 (12)	0.0006 (11)
O3	0.0376 (11)	0.0269 (10)	0.0455 (12)	0.0001 (9)	−0.0024 (9)	−0.0130 (9)
O4	0.0404 (12)	0.0309 (11)	0.0398 (11)	−0.0067 (9)	0.0066 (10)	−0.0012 (9)
C12	0.0465 (19)	0.0299 (16)	0.0523 (19)	−0.0013 (14)	−0.0103 (15)	−0.0127 (14)
C3	0.0360 (16)	0.0191 (13)	0.0200 (13)	0.0062 (11)	0.0016 (11)	0.0015 (10)
O1	0.0382 (11)	0.0255 (10)	0.0250 (9)	0.0069 (8)	0.0059 (8)	−0.0018 (7)
C19	0.0297 (15)	0.0248 (14)	0.0357 (16)	0.0021 (11)	0.0056 (12)	0.0023 (12)
C21	0.056 (2)	0.0320 (16)	0.0453 (18)	0.0079 (14)	0.0160 (15)	−0.0030 (14)
O11	0.0467 (13)	0.0299 (11)	0.0362 (12)	0.0089 (9)	0.0002 (9)	0.0039 (9)
C4	0.0328 (15)	0.0233 (13)	0.0226 (13)	0.0003 (11)	0.0028 (11)	0.0037 (11)
C13	0.0288 (15)	0.0253 (14)	0.0376 (17)	−0.0033 (11)	0.0001 (12)	0.0016 (12)
O5	0.0273 (11)	0.0380 (12)	0.0585 (13)	0.0041 (9)	0.0055 (10)	0.0100 (10)
O6	0.0507 (14)	0.0471 (13)	0.0295 (11)	0.0109 (10)	−0.0072 (10)	−0.0024 (9)
C14	0.0300 (17)	0.046 (2)	0.089 (3)	0.0104 (15)	−0.0042 (17)	0.0166 (18)
C5	0.0312 (14)	0.0211 (13)	0.0222 (13)	0.0017 (11)	0.0017 (11)	−0.0018 (10)
C6	0.0332 (16)	0.0191 (13)	0.0249 (13)	0.0046 (11)	0.0015 (11)	−0.0010 (10)
C15	0.0379 (17)	0.0239 (14)	0.0322 (15)	0.0042 (12)	0.0085 (13)	−0.0016 (12)
O7	0.0388 (12)	0.0264 (10)	0.0407 (11)	−0.0077 (8)	0.0053 (9)	−0.0001 (8)
O8	0.0510 (14)	0.0338 (12)	0.0592 (14)	0.0042 (10)	0.0076 (11)	0.0218 (11)
C16	0.050 (2)	0.0415 (18)	0.061 (2)	−0.0147 (15)	0.0181 (17)	0.0004 (16)

Geometric parameters (Å, º)

C1—C2	1.509 (3)	O5—C14	1.449 (3)
C1—C8	1.549 (3)	C6—C15	1.478 (4)
C1—C5	1.562 (3)	C15—O8	1.202 (3)
C2—C3	1.322 (4)	C15—O7	1.343 (3)
C3—C4	1.501 (3)	O7—C16	1.445 (3)
C4—C5	1.547 (3)	C22—H22A	0.9800
C5—C6	1.511 (3)	C22—H22B	0.9800
C6—C7	1.330 (4)	C22—H22C	0.9800
C7—C8	1.503 (3)	C8—H8	1.0000
O2—C20	1.364 (3)	C18—H18A	0.9800
O2—C7	1.378 (3)	C18—H18B	0.9800
C20—O12	1.193 (3)	C18—H18C	0.9800
C20—C22	1.490 (4)	C1—H1	1.0000
C8—C17	1.515 (3)	C12—H12A	0.9800
C17—O10	1.195 (3)	C12—H12B	0.9800
C17—O9	1.344 (3)	C12—H12C	0.9800
O9—C18	1.444 (3)	C21—H21A	0.9800
C2—C11	1.479 (4)	C21—H21B	0.9800
C11—O4	1.201 (3)	C21—H21C	0.9800
C11—O3	1.333 (3)	C4—H4	1.0000
O3—C12	1.439 (3)	C14—H14A	0.9800
C3—O1	1.390 (3)	C14—H14B	0.9800
O1—C19	1.376 (3)	C14—H14C	0.9800
C19—O11	1.193 (3)	C5—H5	1.0000
C19—C21	1.488 (4)	C16—H16A	0.9800
C4—C13	1.509 (4)	C16—H16B	0.9800
C13—O6	1.197 (3)	C16—H16C	0.9800
C13—O5	1.336 (3)	O2—O1	5.832 (2)
C19—O1—C3	117.26 (19)	C20—C22—H22A	109.5
C20—O2—C7	117.4 (2)	C20—C22—H22B	109.5
O12—C20—O2	122.7 (2)	H22A—C22—H22B	109.5
O12—C20—C22	126.4 (3)	C20—C22—H22C	109.5
O2—C20—C22	110.8 (2)	H22A—C22—H22C	109.5
C6—C7—O2	126.8 (2)	H22B—C22—H22C	109.5
C6—C7—C8	114.3 (2)	C7—C8—H8	110.8
O2—C7—C8	118.9 (2)	C17—C8—H8	110.8
C7—C8—C17	109.2 (2)	C1—C8—H8	110.8
C7—C8—C1	102.0 (2)	O9—C18—H18A	109.5
C17—C8—C1	113.1 (2)	O9—C18—H18B	109.5
O10—C17—O9	123.7 (2)	H18A—C18—H18B	109.5
O10—C17—C8	125.7 (2)	O9—C18—H18C	109.5
O9—C17—C8	110.6 (2)	H18A—C18—H18C	109.5
C17—O9—C18	115.4 (2)	H18B—C18—H18C	109.5
C2—C1—C8	112.1 (2)	C2—C1—H1	111.5
C2—C1—C5	103.08 (19)	C8—C1—H1	111.5
C8—C1—C5	106.62 (19)	C5—C1—H1	111.5
C3—C2—C11	128.3 (2)	O3—C12—H12A	109.5
C3—C2—C1	111.2 (2)	O3—C12—H12B	109.5
C11—C2—C1	120.5 (2)	H12A—C12—H12B	109.5
O4—C11—O3	123.5 (2)	O3—C12—H12C	109.5
O4—C11—C2	123.3 (2)	H12A—C12—H12C	109.5
O3—C11—C2	113.2 (2)	H12B—C12—H12C	109.5
C11—O3—C12	115.5 (2)	C19—C21—H21A	109.5
C2—C3—O1	126.7 (2)	C19—C21—H21B	109.5
C2—C3—C4	114.4 (2)	H21A—C21—H21B	109.5
O1—C3—C4	118.9 (2)	C19—C21—H21C	109.5
O11—C19—O1	122.1 (2)	H21A—C21—H21C	109.5
O11—C19—C21	127.3 (2)	H21B—C21—H21C	109.5
O1—C19—C21	110.6 (2)	C3—C4—H4	111.1
C3—C4—C13	108.2 (2)	C13—C4—H4	111.1
C3—C4—C5	101.9 (2)	C5—C4—H4	111.1
C13—C4—C5	113.0 (2)	O5—C14—H14A	109.5
O6—C13—O5	124.1 (3)	O5—C14—H14B	109.5
O6—C13—C4	125.3 (3)	H14A—C14—H14B	109.5
O5—C13—C4	110.5 (2)	O5—C14—H14C	109.5
C13—O5—C14	115.0 (2)	H14A—C14—H14C	109.5
C6—C5—C4	113.1 (2)	H14B—C14—H14C	109.5
C6—C5—C1	103.2 (2)	C6—C5—H5	111.3
C4—C5—C1	106.35 (19)	C4—C5—H5	111.3
C7—C6—C15	123.5 (2)	C1—C5—H5	111.3
C7—C6—C5	111.2 (2)	O7—C16—H16A	109.5
C15—C6—C5	125.3 (2)	O7—C16—H16B	109.5
O8—C15—O7	123.4 (3)	H16A—C16—H16B	109.5
O8—C15—C6	125.1 (3)	O7—C16—H16C	109.5
O7—C15—C6	111.5 (2)	H16A—C16—H16C	109.5
C15—O7—C16	114.6 (2)	H16B—C16—H16C	109.5
C1—C2—C3—C4	3.1 (3)	C17—C8—C1—C2	147.1 (2)
C2—C3—C4—C5	−13.2 (3)	C17—C8—C1—C5	−100.8 (2)
C3—C4—C5—C6	−95.3 (2)	C8—C1—C2—C3	122.7 (2)
C3—C4—C5—C1	17.3 (2)	C5—C1—C2—C3	8.4 (3)
C4—C5—C6—C7	122.2 (2)	C8—C1—C2—C11	−59.3 (3)
C5—C6—C7—C8	3.1 (3)	C5—C1—C2—C11	−173.6 (2)
C6—C7—C8—C1	−12.5 (3)	O4—C11—O3—C12	4.5 (4)
C7—C8—C1—C5	16.3 (2)	C2—C11—O3—C12	−176.2 (2)
C1—C2—C11—O3	173.1 (2)	C11—C2—C3—O1	5.5 (4)
C1—C2—C11—O4	−7.6 (4)	C1—C2—C3—O1	−176.6 (2)
C3—C2—C11—O3	−9.2 (4)	C11—C2—C3—C4	−174.8 (2)
C3—C2—C11—O4	170.1 (3)	C3—O1—C19—O11	−9.3 (4)
C5—C6—C15—O7	−5.0 (3)	C3—O1—C19—C21	170.9 (2)
C5—C6—C15—O8	175.8 (3)	C2—C3—C4—C13	106.2 (3)
C7—C6—C15—O7	173.4 (2)	O1—C3—C4—C13	−74.1 (3)
C7—C6—C15—O8	−5.9 (4)	O1—C3—C4—C5	166.5 (2)
C2—C3—O1—C19	−78.7 (3)	C3—C4—C13—O6	−92.7 (3)
C4—C3—O1—C19	101.6 (3)	C5—C4—C13—O6	19.3 (4)
C6—C7—O2—C20	−70.4 (3)	C3—C4—C13—O5	85.9 (2)
C8—C7—O2—C20	110.4 (3)	C5—C4—C13—O5	−162.1 (2)
O8—C15—O7—C16	−3.1 (4)	O6—C13—O5—C14	7.1 (4)
C6—C15—O7—C16	177.6 (2)	C4—C13—O5—C14	−171.5 (2)
C7—O2—C20—O12	−12.1 (4)	C13—C4—C5—C6	148.8 (2)
C7—O2—C20—C22	169.0 (2)	C13—C4—C5—C1	−98.6 (2)
C6—C7—C8—C17	107.4 (3)	C2—C1—C5—C6	103.3 (2)
O2—C7—C8—C17	−73.3 (3)	C8—C1—C5—C6	−14.9 (2)
O2—C7—C8—C1	166.8 (2)	C2—C1—C5—C4	−16.0 (2)
C7—C8—C17—O10	−95.5 (3)	C8—C1—C5—C4	−134.2 (2)
C1—C8—C17—O10	17.2 (4)	O2—C7—C6—C15	5.4 (4)
C7—C8—C17—O9	83.5 (3)	C8—C7—C6—C15	−175.4 (2)
C1—C8—C17—O9	−163.7 (2)	O2—C7—C6—C5	−176.1 (2)
O10—C17—O9—C18	0.7 (4)	C1—C5—C6—C7	7.7 (3)
C8—C17—O9—C18	−178.3 (2)	C4—C5—C6—C15	−59.3 (3)
C7—C8—C1—C2	−95.8 (2)	C1—C5—C6—C15	−173.8 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···O6^i	1.00	2.35	3.290 (3)	156
C8—H8···O10^i	1.00	2.33	3.138 (3)	137
C5—H5···O1^ii	1.00	2.63	3.614 (3)	168

Symmetry codes: (i) x, −y+3/2, z−1/2; (ii) x, −y+3/2, z+1/2.