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Investigations into the construction of the penta­substituted ring C of Neosurugatoxin – a crystallographic study

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aDepartment of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE, Scotland, and bDivision of Chemistry and Environmental Science, School of Science and the Environment, Faculty of Science and Engineering, Manchester Metropolitan University, John Dalton Building, Chester Street, Manchester M1 5GD, England
*Correspondence e-mail: a.m.jones@mmu.ac.uk, w.harrison@abdn.ac.uk

Edited by M. Gdaniec, Adam Mickiewicz University, Poland (Received 23 October 2015; accepted 7 December 2015; online 1 January 2016)

The crystal structures of three cyclo­penta­[c]furans with various substituents at the 4-, 5- and 6-positions of the ring system are reported, namely, (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-4,5-diol, C14H18O3, (I), (±)-(3aR,4S,5S,6aS)-4-benz­yloxy-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-5-ol, C21H24O3, (II), and (±)-(1aR,1bS,4aR,5S,5aR)-5-benz­yloxy-5-methyl-5a-phenyl­hexa­hydro-2H-oxireno[2′,3′:3,4]cyclopenta­[1,2-c]furan, C21H22O3, (III). The dominant inter­action in (I) and (II) is an O—H⋯O hydrogen bond across the bicyclic 5,5-ring system between the non-functionalized hy­droxy group and the tetra­hydro­furan O atom, which appears to influence the envelope conformations of the fused five-membered rings, whereas in (III), the rings have different conformations. A weak intra­molecular C—H⋯O inter­action appears to influence the degree of tilt of the phenyl ring attached to the 5-position and is different in (I) compared to (II) and (III).

1. Chemical context

Neosurugatoxin, C30H34BrN5O15, is the causative agent behind the toxicity of the Japanese ivory shell, Babylonia Japonica, a shellfish widely consumed in Japan. Neosurugatoxin, shown in Scheme 1[link] below, was first isolated and the structure delineated using X-ray crystallographic studies by Kosuge and co-workers (Kosuge et al., 1981[Kosuge, T., Tsuji, K., Hirai, K., Yamaguchi, K., Okamoto, T. & Iitaka, Y. (1981). Tetrahedron Lett. 22, 3417-3420.], 1982[Kosuge, T., Tsuji, K. & Hirai, K. (1982). Chem. Pharm. Bull. 30, 3255-3259.]).

[Scheme 1]

Biological studies with Neosurugatoxin have shown it to have a wide range of actions on the central nervous system including: potent nicotinic acetyl­choline receptor antagonist (Yamada et al., 1988[Yamada, S., Ushijima, H., Nakayama, K., Hayashi, E., Tsuji, K. & Kosuge, T. (1988). Eur. J. Pharmacol. 156, 279-282.]; Bai & Sattelle, 1993[Bai, D. & Sattelle, D. B. (1993). Arch. Insect Biochem. Physiol. 23, 161-167.]; Tornøe et al., 1995[Tornøe, C., Bai, D., Holden-Dye, L., Abramson, S. N. & Sattelle, D. B. (1995). Toxicon, 33, 411-424.]); inhibition of acetyl­choline release and blockage of muscle and neuronal nicotinic receptors (Hong et al., 1992[Hong, S. J., Tsuji, J. & Chang, C. C. (1992). Neuroscience, 48, 727-735.]); and a central action upon nicotinic cholinoreceptors (Bisset et al., 1992[Bisset, G. W., Fairhall, K. M. & Tsuji, K. (1992). Br. J. Pharmacol. 106, 685-692.]). Alternative total syntheses of Neosurugatoxin have previously been reported by the Inoue and Okada groups (Inoue et al., 1986[Inoue, S., Okada, K., Tanino, H. & Kakoi, H. (1986). Tetrahedron Lett. 27, 5225-5228.], 1994[Inoues, S., Okada, K., Tanino, H. & Kakoi, H. (1994). Tetrahedron, 50, 2753-2770.]; Okada et al., 1989[Okada, K., Mizuno, Y., Tanino, H., Kakoi, H. & Inoue, S. (1989). Chem. Lett. pp. 703-706.]). Intrigued by the dense functionality and complexity of ring C in Neosurugatoxin (see Scheme 1[link]), we investigated a synthetic route to novel simplified cyclo­penta­nes with diversity vectors to install the required functionality at a later stage.

[Scheme 2]

As part of these studies, we now report the crystal structures of three of these compounds, namely (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-4,5-diol, C14H18O3, (I)[link], (±)-(3aR,4S,5S,6aS)-4-benz­yloxy-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-5-ol, C21H24O3, (II)[link], and (±)-(1aR,1bS,4aR,5S,5aR)-5-benz­yloxy-5-methyl-5a-phenyl­hexa­hydro-2H-oxireno[2′,3′:3,4]cyclo­penta­[1,2-c]furan, C21H22O3, (III)[link], see Scheme 2 above.

2. Structural commentary

Compound (I)[link] crystallizes in the centrosymmetric space group Pbca and its mol­ecular structure is illustrated in Fig. 1[link]. In the arbitrarily chosen asymmetric mol­ecule, the configurations of the stereogenic atoms C1, C2, C6 and C7 are S, R, R, and R, respectively. As expected, the junction of the fused rings is cis (H1—C1—C2—H2 = 5°). The C1/C2/C3/O1/C4 ring has an envelope conformation, with O1 displaced from the mean plane of the carbon atoms (r.m.s. deviation = 0.018 Å) by 0.566 (5) Å. The C1/C2/C5/C6/C7 ring also has an envelope conformation, with C6 displaced from the other atoms (r.m.s. deviation = 0.026 Å) by 0.573 (6) Å. The dihedral angle between the almost planar parts of the rings is 58.3 (2)°: the overall shape could be described as a butterfly, with the flap atoms (O1 and C6) pointing inwards. Atoms O2 and O3 lie to the same face of the ring although there is a significant twist between them [O2—C6—C7—O3 = 46.5 (4)°]. The O2—C6—C7—C8 torsion angle is 164.9 (3)° and the C8—C7—C6—C9 torsion angle is 47.6 (4)°. The dihedral angle between the pendant benzene ring (C9–C14) and C1/C2/C5/C7 is 64.00 (17)°. The mol­ecular structure of (I)[link] features two intra­molecular O—H⋯O hydrogen bonds (Table 1[link]). The O3—H3o⋯O2 bond closes an S(5) ring. The O2—H2o⋯O1 bond, which bridges across the top of the fused-ring system to generate an S(7) ring, may influence the conformations of the five-membered rings. An intra­molecular C10—H10⋯O2 short contact (H⋯O = 2.33 Å) is also present: although the C—H⋯O angle of 100° is extremely small to be regarded as a bond (Steiner, 1996[Steiner, T. (1996). Crystallogr. Rev. 6, 1-51.]) it is inter­esting to compare this C—H grouping to the situation in (II)[link] and (III)[link] (vide infra).

Table 1
Hydrogen-bond geometry (Å, °) for (I)[link]

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2o⋯O1 0.84 (4) 1.96 (4) 2.776 (4) 163 (4)
O3—H3o⋯O1i 0.80 (4) 2.11 (4) 2.844 (4) 151 (4)
O3—H3o⋯O2 0.80 (4) 2.28 (4) 2.744 (3) 118 (4)
C10—H10⋯O2 0.95 2.33 2.667 (5) 100
Symmetry code: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, z].
[Figure 1]
Figure 1
The mol­ecular structure of (I)[link], showing 50% probability displacement ellipsoids. Intra­molecular O—H⋯O and C—H⋯O inter­actions are shown as black and pink double-dashed lines, respectively.

The asymmetric unit of (II)[link], which crystallizes in the centrosymmetric space group P21/c, contains one mol­ecule (Fig. 2[link]): for ease of comparison with (I)[link], the stereogenic centres in this mol­ecule have configurations of S, R, R, and R, for C1, C2, C7 and C8, respectively. As with (I)[link], the C1/C2/C3/O1/C4 ring has an envelope conformation, with O1 as the flap, displaced by 0.571 (2) Å from the other atoms. The conformation of the C1/C2/C5/C6/C7 ring in (II)[link] is also an envelope, with C6 as the flap [displacement = 0.618 (2) Å]. The dihedral angle between C1/C2/C3/C4 (r.m.s. deviation = 0.004 Å) and C1/C2/C5/C7 (r.m.s. deviation = 0.016 Å) of 58.28 (7)° is identical to the equivalent value for (I)[link] and the flap atoms (O1 and C6) also point inwards. Key torsion angles in (II)[link] include O2—C6—C7—O3 [42.19 (17)°], O2—C6—C7—C8 [164.41 (13)°] and C8—C7—C6—C9 [46.42 (17)°]: these data are similar to the corresponding values for (I)[link]. However, the dihedral angle between the C9–C14 benzene ring and C1/C2/C5/C7 in (II)[link] is 34.90 (9)°, which differs by some 30° compared to the equivalent value for (I)[link]. The dihedral angle between the aromatic rings (C9–C14 and C16–C21) is 89.74 (5)°. As with (I)[link], the hy­droxy (O2—H2o) grouping forms an intra­molecular hydrogen bond (Table 2[link]) to O1 across the fused-ring system and an S(7) ring results. The C10—H10 grouping in (II)[link] points towards O3 rather than O2 (H⋯O = 2.56 Å), which appears to correlate with the different orientation of the C9–C14 ring.

Table 2
Hydrogen-bond geometry (Å, °) for (II)[link]

Cg4 is the centroid of the C16–C21 ring.

D—H⋯A D—H H⋯A DA D—H⋯A
O2—H2o⋯O1 0.87 (2) 1.93 (2) 2.7794 (17) 162.9 (18)
C10—H10⋯O3 0.95 2.56 3.091 (2) 116
C5—H5A⋯O2i 0.99 2.58 3.266 (2) 126
C19—H19⋯O1ii 0.95 2.58 3.344 (2) 138
C12—H12⋯Cg4iii 0.95 2.74 3.6619 (19) 165
Symmetry codes: (i) [x, -y+{\script{3\over 2}}, z-{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+2; (iii) -x, -y+1, -z+2.
[Figure 2]
Figure 2
The mol­ecular structure of (II)[link], showing 50% probability displacement ellipsoids. Intra­molecular O—H⋯O and C—H⋯O inter­actions are shown as black and pink double-dashed lines, respectively.

Compound (III)[link] crystallizes in the chiral space group P212121. The absolute structure was indeterminate in the present experiment and C1, C2, C5, C6 and C7 in the asymmetric mol­ecule were assigned configurations of S, R, S, S and R, respectively (Fig. 3[link]). Based on the synthesis, we assume the bulk sample to be racemic. The conformation of the C1/C2/C3/O1/C4 ring is different to the equivalent unit in (I)[link] and (II)[link]: in (III)[link], this ring is twisted about the C2—C3 bond [Q(2) = 0.307 (10) Å, φ(2) = 232.5 (18)°] such that C2 and C3 are displaced from the O1/C4/C1 plane by −0.22 (2) and 0.29 (2) Å, respectively. The C1/C2/C5/C6/C7 conformation in (III)[link] is an envelope, but the flap atom is different to that in (I)[link] and (II)[link]: in this case C1 (rather than C6) is displaced by 0.487 (14) Å from the other atoms (r.m.s. deviation = 0.011 Å). The dihedral angle between the five-membered rings (all atoms) of 69.6 (5)° in (III)[link] is significantly larger than the corresponding angle for (I)[link] and (II)[link]. The epoxide ring (C5/C6/O2) subtends a dihedral angle of 74.0 (4)° with respect to C2/C5/C6/C7. Important torsion angles in (III)[link] include O2—C6—C7—O3 [76.3 (8)°], O2—C6—C7—C8 [–161.3 (6)°] and C8—C7—C6—C9 [55.4 (9)°]: these data are very different from the corresponding values for (I)[link] and (II)[link], which must in part be due to the steric inflexibility of the epoxide ring containing O2. The dihedral angle between the C9–C14 benzene ring and C2/C5/C6/C7 in (II)[link] is 49.3 (4)°, which is inter­mediate between the corresponding values for (I)[link] and (II)[link]. The dihedral angle between the C9–C14 and C16a–C21a benzene rings is 41.0 (7)°. There are obviously no classical intra­molecular hydrogen bonds in (III)[link], but, as in (II)[link], a C10—H10⋯O3 link (Table 3[link]) is seen.

Table 3
Hydrogen-bond geometry (Å, °) for (III)[link]

Cg6 is the centroid of the C16a–C21a ring.

D—H⋯A D—H H⋯A DA D—H⋯A
C10—H10⋯O3 0.95 2.57 3.124 (10) 117
C8—H8B⋯O2i 0.98 2.58 3.462 (10) 150
C14—H14⋯O2ii 0.95 2.57 3.450 (11) 155
C4—H4BCg6iii 0.99 2.65 3.569 (10) 154
Symmetry codes: (i) x+1, y, z; (ii) [x+{\script{1\over 2}}, -y+{\script{3\over 2}}, -z]; (iii) [-x+1, y+{\script{1\over 2}}, -z+{\script{1\over 2}}].
[Figure 3]
Figure 3
The mol­ecular structure of (III)[link], showing 50% probability displacement ellipsoids. Only one orientation of the disordered C16–C21 benzene ring is shown. The intra­molecular C—H⋯O inter­action is shown as a pink double-dashed line.

3. Supra­molecular features

In the crystal of (I)[link], the mol­ecules are linked into [010] chains by O3—H3o⋯O1i [symmetry code: (i) [1\over2] − x, y − [1\over2], z] hydrogen bonds (Table 1[link], Fig. 4[link]): the same OH group also participates in an intra­molecular bond, as described above. Adjacent mol­ecules are enanti­omers, being related by b-glide symmetry and the chain has a C(6) motif. Long and presumably very weak inter­molecular C—H⋯O and C—H⋯π inter­actions (Tables 2[link] and 3[link]) are observed in the crystals of (II)[link] and (III)[link]. Assuming these inter­actions to be significant, (100) sheets in (II)[link] and [100] chains in (III)[link] arise (Fig. 5[link]). It is notable that the epoxide O atom accepts both C—H⋯O inter­actions in the latter. Aromatic ππ stacking is absent in these structures, the shortest centroid–centroid separations being ca 4.97 in (I)[link], 5.03 in (II)[link] and 5.24 Å in (III)[link].

[Figure 4]
Figure 4
Partial packing diagram for (I)[link], showing the formation of [100] chains linked by O—H⋯O hydrogen bonds (double-dashed lines). Symmetry codes as in Table 1[link]. All C-bonded H atoms have been omitted for clarity.
[Figure 5]
Figure 5
Partial packing diagram for (III)[link], showing the formation of [100] chains linked by C—H⋯O hydrogen bonds (double-dashed lines). Symmetry codes as in Table 3[link]. All H atoms except those involved in the C—H⋯O bonds have been omitted for clarity.

4. Database survey

A search of the Cambridge Structural Database (Groom & Allen, 2014[Groom, C. R. & Allen, F. H. (2014). Angew. Chem. Int. Ed. 53, 662-671.]) for compounds with a cyclo­penta­[c]furan skeleton revealed 321 matches; of these, just two had O atoms bonded to the 4- and 5-positions of the fused-ring system, viz.: VALFIX (Dumdei et al., 1989[Dumdei, E. J., De Silva, E. D., Andersen, R. J., Choudhary, M. I. & Clardy, J. (1989). J. Am. Chem. Soc. 111, 2712-2713.]) and YEYBEB (Wang et al., 2012[Wang, H., Kohler, P., Overman, L. E. & Houk, K. N. (2012). J. Am. Chem. Soc. 134, 16054-16058.]), but otherwise, neither bears a close resemblance to the compounds described here.

5. Synthesis and crystallization

Full synthesis details will be reported in due course, but a summary of the steps followed to prepare (I)[link], (II)[link] and (III)[link] are detailed as follows. A Pauson–Khand [2 + 2 + 1] cyclo­addition (Pauson, 1985[Pauson, P. L. (1985). Tetrahedron, 41, 5855-5860.]) was used to prepare the key starting material: a mixture of phenyl­acetyl­ene, 2,5-di­hydro­furan and dicobalt octa­carbonyl in toluene under an inert atmosphere was heated to reflux for 1 h to afford (±)-(3aR,6aS)-5-phenyl-1,3,3a,6a-tetra­hydro-4H-cyclo­penta­[c]furan-4-one, A[link]: after purification by silica gel chromatography, spectroscopic data were in accordance with those previously reported by Brown et al. (2005[Brown, J. A., Irvine, S., Kerr, W. J. & Pearson, C. M. (2005). Org. Biomol. Chem. 3, 2396-2398.]). Treatment of A[link] with methyl magnesium iodide in anhydrous tetra­hydro­furan using the procedure of Coote et al. (2008[Coote, S. C., O'Brien, P. & Whitwood, A. C. (2008). Org. Biomol. Chem. 6, 4299-4314.]) afforded (±)-(3aR,4S,6aS)-4-methyl-5-phenyl-3,3a,4,6a-tetra­hydro-1H-cyclo­penta­[c]furan-4-ol, B[link]. Treatment of B[link] with m-CPBA in anhydrous di­chloro­methane at 273 K yielded (±)-(1aR,1bS,4aR,5S,5aR)-5-methyl-5a-phenyl­hexa­hydro-2H-oxireno[2′,3′:3,4]cyclo­penta­[1,2-c]furan-5-ol, C[link], with facial selectivity directed by the hy­droxy group (Langston et al., 2007[Langston, S. P., Olhava, E. J. & Vyskocil, S. (2007). PCT Int. Appl. WO 2007092213.]). Treatment of C with lithium aluminium hydride in anhydrous tetra­hydro­furan (Howe et al., 1987[Howe, G. P., Wang, S. & Procter, G. (1987). Tetrahedron Lett. 28, 2629-2632.]) afforded the epoxide opened product, (±)-(3aR,4S,5S,6aS)-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-4,5-diol, (I)[link]. Further treatment of (I)[link] with benzyl chloride under identical conditions to above afforded (±)-(3aR,4S,5S,6aS)-4-(benz­yloxy)-4-methyl-5-phenyl­hexa­hydro-1H-cyclo­penta­[c]furan-5-ol, (II)[link]. Benzyl­ation of C using the procedure of Peng & Woerpel (2003[Peng, Z.-H. & Woerpel, K. A. (2003). J. Am. Chem. Soc. 125, 6018-6019.]) afforded (±)-(1aR,1bS,4aR,5S,5aR)-5-(benz­yloxy)-5-methyl-5a-phenyl­hexa­hydro-2H-oxireno[2′,3′:3,4]cyclo­penta­[1,2-c]furan, (III)[link].

[Scheme 3]

6. Refinement

Crystal data, data collection and structure refinement details for (I)–(III)[link] are summarized in Table 4[link]. The O-bound H atoms were located in difference maps and their positions freely refined. The C-bound H atoms were geometrically placed (C—H = 0.95–1.00 Å) and refined as riding atoms. The constraint Uiso(H) = 1.2Ueq(carrier) or 1.5Ueq(methyl carrier) was applied in all cases. The methyl H atoms were allowed to rotate, but not to tip, to best fit the electron density. The C16–C21 benzene ring in (III)[link] was modelled as being disordered over two overlapped orientations in a 0.54 (3):0.46 (3) ratio; the rings were constrained to be regular hexa­gons (C—C = 1.39 Å). The crystal quality for (I)[link] and (III)[link] was poor, which may correlate with the rather high R-factors obtained, although the structures are clearly resolved with acceptable geometrical precision. The absolute structure of compound (III)[link] was indeterminate in the present experiment.

Table 4
Experimental details

  (I) (II) (III)
Crystal data
Chemical formula C14H18O3 C21H24O3 C21H22O3
Mr 234.28 324.40 322.39
Crystal system, space group Orthorhombic, Pbca Monoclinic, P21/c Orthorhombic, P212121
Temperature (K) 120 120 120
a, b, c (Å) 10.997 (2), 7.7489 (9), 27.852 (4) 12.8872 (3), 19.3544 (6), 6.8046 (1) 5.6392 (2), 11.0427 (5), 26.6311 (13)
α, β, γ (°) 90, 90, 90 90, 92.3907 (16), 90 90, 90, 90
V3) 2373.4 (6) 1695.75 (7) 1658.37 (13)
Z 8 4 4
Radiation type Mo Kα Mo Kα Mo Kα
μ (mm−1) 0.09 0.08 0.09
Crystal size (mm) 0.18 × 0.08 × 0.02 0.14 × 0.10 × 0.04 0.34 × 0.14 × 0.04
 
Data collection
Diffractometer Nonius KappaCCD Nonius KappaCCD Nonius KappaCCD
No. of measured, independent and observed [I > 2σ(I)] reflections 13446, 2312, 1303 28187, 3899, 2834 12562, 2221, 1867
Rint 0.137 0.091 0.073
(sin θ/λ)max−1) 0.617 0.651 0.650
 
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.095, 0.148, 1.09 0.053, 0.132, 1.06 0.123, 0.279, 1.17
No. of reflections 2312 3899 2221
No. of parameters 161 222 190
H-atom treatment H atoms treated by a mixture of independent and constrained refinement H atoms treated by a mixture of independent and constrained refinement H-atom parameters constrained
       
Δρmax, Δρmin (e Å−3) 0.25, −0.27 0.30, −0.23 0.40, −0.44
Computer programs: COLLECT (Nonius, 1998[Nonius, B. V. (1998). COLLECT. Nonius BV, Delft, The Netherlands.]), DENZO and SCALEPACK (Otwinowski & Minor, 1997[Otwinowski, Z. & Minor, W. (1997). Methods in Enzymology, Vol. 276, Macromolecular Crystallography, Part A, edited by C. W. Carter Jr & R. M. Sweet, pp. 307-326. New York: Academic Press.]), and SORTAV (Blessing, 1995[Blessing, R. H. (1995). Acta Cryst. A51, 33-38.]), SHELXS97 and SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]) and ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]).

Supporting information


Computing details top

For all compounds, data collection: COLLECT (Nonius, 1998); cell refinement: SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1997), and SORTAV (Blessing, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

(I) (±)-(3aR,4S,5S,6aS)-4-Methyl-5-phenylhexahydro-1H-cyclopenta[c]furan-4,5-diol top
Crystal data top
C14H18O3Dx = 1.311 Mg m3
Mr = 234.28Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, PbcaCell parameters from 4280 reflections
a = 10.997 (2) Åθ = 2.9–27.5°
b = 7.7489 (9) ŵ = 0.09 mm1
c = 27.852 (4) ÅT = 120 K
V = 2373.4 (6) Å3Lath, colourless
Z = 80.18 × 0.08 × 0.02 mm
F(000) = 1008
Data collection top
Nonius KappaCCD
diffractometer
1303 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.137
Graphite monochromatorθmax = 26.0°, θmin = 3.3°
ω scansh = 1313
13446 measured reflectionsk = 69
2312 independent reflectionsl = 3434
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.095Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.148H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0231P)2 + 2.9549P]
where P = (Fo2 + 2Fc2)/3
2312 reflections(Δ/σ)max < 0.001
161 parametersΔρmax = 0.25 e Å3
0 restraintsΔρmin = 0.27 e Å3
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/Ueq
C10.4979 (4)0.7625 (5)0.44924 (12)0.0240 (10)
H10.55790.77360.47600.029*
C20.5209 (4)0.9051 (4)0.41050 (13)0.0251 (10)
H20.59510.97390.41850.030*
C30.4068 (4)1.0179 (5)0.41288 (13)0.0285 (10)
H3A0.41891.11560.43530.034*
H3B0.38631.06410.38080.034*
C40.3697 (4)0.8034 (5)0.46709 (13)0.0292 (11)
H4A0.32370.69550.47280.035*
H4B0.37330.86950.49750.035*
C50.5380 (4)0.8075 (4)0.36269 (12)0.0252 (10)
H5A0.49570.86870.33630.030*
H5B0.62540.79900.35460.030*
C60.4840 (4)0.6287 (4)0.36962 (12)0.0221 (9)
C70.5147 (4)0.5877 (4)0.42306 (12)0.0207 (9)
C80.6451 (4)0.5287 (5)0.43001 (12)0.0254 (10)
H8A0.65780.41960.41290.038*
H8B0.66100.51200.46430.038*
H8C0.70060.61640.41730.038*
C90.5241 (4)0.4920 (5)0.33435 (11)0.0235 (10)
C100.4430 (4)0.3631 (5)0.31982 (13)0.0301 (11)
H100.36280.36140.33250.036*
C110.4784 (5)0.2378 (5)0.28707 (15)0.0404 (13)
H110.42240.15050.27790.048*
C120.5939 (5)0.2384 (6)0.26765 (14)0.0430 (14)
H120.61740.15340.24490.052*
C130.6743 (5)0.3641 (5)0.28186 (13)0.0353 (12)
H130.75420.36570.26890.042*
C140.6403 (4)0.4878 (5)0.31469 (12)0.0303 (11)
H140.69780.57270.32420.036*
O10.3123 (3)0.9043 (3)0.43001 (9)0.0297 (7)
O20.3534 (3)0.6375 (3)0.36550 (9)0.0270 (7)
H2o0.328 (4)0.722 (5)0.3816 (13)0.032*
O30.4425 (3)0.4516 (3)0.44161 (9)0.0280 (8)
H3o0.375 (4)0.464 (5)0.4309 (14)0.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.016 (3)0.031 (2)0.0249 (19)0.0010 (19)0.0017 (19)0.0017 (17)
C20.018 (3)0.018 (2)0.039 (2)0.0007 (19)0.000 (2)0.0036 (17)
C30.031 (3)0.022 (2)0.033 (2)0.000 (2)0.006 (2)0.0035 (17)
C40.031 (3)0.028 (2)0.029 (2)0.008 (2)0.007 (2)0.0026 (18)
C50.023 (3)0.026 (2)0.027 (2)0.0007 (19)0.0027 (19)0.0022 (17)
C60.018 (3)0.021 (2)0.028 (2)0.0039 (19)0.0048 (19)0.0027 (17)
C70.018 (3)0.023 (2)0.0213 (18)0.0007 (18)0.0035 (18)0.0011 (16)
C80.026 (3)0.028 (2)0.023 (2)0.002 (2)0.0040 (19)0.0017 (16)
C90.035 (3)0.022 (2)0.0139 (18)0.004 (2)0.0063 (19)0.0021 (16)
C100.036 (3)0.028 (2)0.026 (2)0.002 (2)0.008 (2)0.0031 (19)
C110.058 (4)0.025 (3)0.039 (2)0.004 (3)0.023 (3)0.004 (2)
C120.067 (4)0.033 (3)0.029 (2)0.028 (3)0.013 (3)0.011 (2)
C130.051 (4)0.032 (3)0.024 (2)0.017 (2)0.002 (2)0.0019 (19)
C140.042 (3)0.028 (2)0.0209 (19)0.009 (2)0.003 (2)0.0024 (18)
O10.0226 (19)0.0266 (15)0.0399 (16)0.0066 (13)0.0054 (14)0.0074 (12)
O20.023 (2)0.0290 (17)0.0293 (15)0.0018 (14)0.0068 (14)0.0002 (12)
O30.027 (2)0.0289 (16)0.0283 (15)0.0050 (15)0.0050 (14)0.0076 (12)
Geometric parameters (Å, º) top
C1—C41.528 (5)C7—O31.417 (4)
C1—C71.550 (5)C7—C81.517 (5)
C1—C21.565 (5)C8—H8A0.9800
C1—H11.0000C8—H8B0.9800
C2—C31.530 (5)C8—H8C0.9800
C2—C51.543 (5)C9—C141.390 (5)
C2—H21.0000C9—C101.399 (5)
C3—O11.444 (4)C10—C111.388 (5)
C3—H3A0.9900C10—H100.9500
C3—H3B0.9900C11—C121.381 (6)
C4—O11.441 (4)C11—H110.9500
C4—H4A0.9900C12—C131.373 (6)
C4—H4B0.9900C12—H120.9500
C5—C61.519 (5)C13—C141.377 (5)
C5—H5A0.9900C13—H130.9500
C5—H5B0.9900C14—H140.9500
C6—O21.442 (5)O2—H2o0.84 (4)
C6—C91.511 (5)O3—H3o0.80 (4)
C6—C71.559 (5)
C4—C1—C7116.4 (3)C5—C6—C7102.9 (3)
C4—C1—C2103.1 (3)O3—C7—C8105.0 (3)
C7—C1—C2105.9 (3)O3—C7—C1114.3 (3)
C4—C1—H1110.4C8—C7—C1108.4 (3)
C7—C1—H1110.4O3—C7—C6112.2 (3)
C2—C1—H1110.4C8—C7—C6112.8 (3)
C3—C2—C5114.7 (3)C1—C7—C6104.2 (3)
C3—C2—C1103.9 (3)C7—C8—H8A109.5
C5—C2—C1105.6 (3)C7—C8—H8B109.5
C3—C2—H2110.8H8A—C8—H8B109.5
C5—C2—H2110.8C7—C8—H8C109.5
C1—C2—H2110.8H8A—C8—H8C109.5
O1—C3—C2104.9 (3)H8B—C8—H8C109.5
O1—C3—H3A110.8C14—C9—C10117.1 (4)
C2—C3—H3A110.8C14—C9—C6122.7 (4)
O1—C3—H3B110.8C10—C9—C6120.2 (4)
C2—C3—H3B110.8C11—C10—C9120.7 (4)
H3A—C3—H3B108.8C11—C10—H10119.6
O1—C4—C1106.5 (3)C9—C10—H10119.6
O1—C4—H4A110.4C12—C11—C10120.8 (4)
C1—C4—H4A110.4C12—C11—H11119.6
O1—C4—H4B110.4C10—C11—H11119.6
C1—C4—H4B110.4C13—C12—C11118.8 (4)
H4A—C4—H4B108.6C13—C12—H12120.6
C6—C5—C2106.8 (3)C11—C12—H12120.6
C6—C5—H5A110.4C12—C13—C14120.7 (5)
C2—C5—H5A110.4C12—C13—H13119.7
C6—C5—H5B110.4C14—C13—H13119.7
C2—C5—H5B110.4C13—C14—C9121.8 (4)
H5A—C5—H5B108.6C13—C14—H14119.1
O2—C6—C9105.8 (3)C9—C14—H14119.1
O2—C6—C5109.6 (3)C4—O1—C3104.6 (3)
C9—C6—C5116.3 (3)C6—O2—H2o109 (3)
O2—C6—C7107.5 (3)C7—O3—H3o107 (3)
C9—C6—C7114.5 (3)
C4—C1—C2—C33.5 (4)O2—C6—C7—C8164.9 (3)
C7—C1—C2—C3126.2 (3)C9—C6—C7—C847.6 (4)
C4—C1—C2—C5117.5 (3)C5—C6—C7—C879.4 (4)
C7—C1—C2—C55.2 (4)O2—C6—C7—C177.7 (3)
C5—C2—C3—O187.8 (4)C9—C6—C7—C1165.0 (3)
C1—C2—C3—O126.9 (4)C5—C6—C7—C138.0 (4)
C7—C1—C4—O194.2 (3)O2—C6—C9—C14155.7 (3)
C2—C1—C4—O121.2 (4)C5—C6—C9—C1433.8 (5)
C3—C2—C5—C694.9 (4)C7—C6—C9—C1486.1 (4)
C1—C2—C5—C618.9 (4)O2—C6—C9—C1023.8 (4)
C2—C5—C6—O278.9 (4)C5—C6—C9—C10145.7 (3)
C2—C5—C6—C9161.2 (3)C7—C6—C9—C1094.4 (4)
C2—C5—C6—C735.2 (4)C14—C9—C10—C110.2 (5)
C4—C1—C7—O335.5 (4)C6—C9—C10—C11179.4 (3)
C2—C1—C7—O3149.4 (3)C9—C10—C11—C120.7 (6)
C4—C1—C7—C8152.3 (3)C10—C11—C12—C131.0 (6)
C2—C1—C7—C893.9 (3)C11—C12—C13—C140.3 (6)
C4—C1—C7—C687.3 (4)C12—C13—C14—C90.6 (6)
C2—C1—C7—C626.5 (4)C10—C9—C14—C130.8 (5)
O2—C6—C7—O346.5 (4)C6—C9—C14—C13178.7 (3)
C9—C6—C7—O370.7 (4)C1—C4—O1—C339.4 (4)
C5—C6—C7—O3162.2 (3)C2—C3—O1—C441.3 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O2—H2o···O10.84 (4)1.96 (4)2.776 (4)163 (4)
O3—H3o···O1i0.80 (4)2.11 (4)2.844 (4)151 (4)
O3—H3o···O20.80 (4)2.28 (4)2.744 (3)118 (4)
C10—H10···O20.952.332.667 (5)100
Symmetry code: (i) x+1/2, y1/2, z.
(II) (±)-(3aR,4S,5S,6aS)-4-Benzyloxy-4-methyl-5-phenylhexahydro-1H-cyclopenta[c]furan-5-ol top
Crystal data top
C21H24O3F(000) = 696
Mr = 324.40Dx = 1.271 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
a = 12.8872 (3) ÅCell parameters from 3991 reflections
b = 19.3544 (6) Åθ = 2.9–27.5°
c = 6.8046 (1) ŵ = 0.08 mm1
β = 92.3907 (16)°T = 120 K
V = 1695.75 (7) Å3Block, colourless
Z = 40.14 × 0.10 × 0.04 mm
Data collection top
Nonius KappaCCD
diffractometer
2834 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.091
Graphite monochromatorθmax = 27.6°, θmin = 3.2°
ω scansh = 1616
28187 measured reflectionsk = 2522
3899 independent reflectionsl = 88
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)] = 0.053H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.132 w = 1/[σ2(Fo2) + (0.0522P)2 + 0.6264P]
where P = (Fo2 + 2Fc2)/3
S = 1.06(Δ/σ)max < 0.001
3899 reflectionsΔρmax = 0.30 e Å3
222 parametersΔρmin = 0.23 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.015 (2)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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*/Ueq
C10.30147 (13)0.58494 (9)0.3553 (2)0.0281 (4)
H10.29650.55550.23450.034*
C20.29204 (13)0.66286 (9)0.2994 (2)0.0287 (4)
H20.28080.66870.15410.034*
C30.39707 (14)0.69274 (10)0.3697 (3)0.0363 (4)
H3A0.44560.69370.26080.044*
H3B0.38870.74040.41980.044*
C40.40989 (14)0.57980 (10)0.4536 (3)0.0350 (4)
H4A0.41030.54630.56360.042*
H4B0.46070.56440.35760.042*
C50.19910 (13)0.69099 (9)0.4091 (2)0.0269 (4)
H5A0.21340.73850.45690.032*
H5B0.13600.69190.32120.032*
C60.18412 (12)0.64195 (8)0.5828 (2)0.0225 (4)
C70.20787 (13)0.57048 (9)0.4881 (2)0.0242 (4)
C80.11588 (14)0.54513 (9)0.3603 (2)0.0300 (4)
H8A0.13460.50210.29480.045*
H8B0.09720.58020.26110.045*
H8C0.05660.53680.44280.045*
C90.07863 (12)0.64665 (9)0.6741 (2)0.0237 (4)
C100.05847 (13)0.60608 (9)0.8379 (2)0.0284 (4)
H100.11130.57670.89210.034*
C110.03727 (14)0.60800 (10)0.9227 (2)0.0317 (4)
H110.04980.57961.03320.038*
C120.11497 (14)0.65112 (10)0.8471 (2)0.0322 (4)
H120.18100.65210.90420.039*
C130.09541 (14)0.69271 (10)0.6879 (3)0.0321 (4)
H130.14790.72310.63700.039*
C140.00014 (13)0.69059 (9)0.6015 (2)0.0280 (4)
H140.01230.71940.49170.034*
C150.24848 (15)0.45363 (9)0.5913 (2)0.0311 (4)
H15A0.28990.45140.47210.037*
H15B0.18070.43100.56180.037*
C160.30523 (13)0.41712 (9)0.7601 (2)0.0261 (4)
C170.31224 (14)0.34524 (9)0.7586 (3)0.0295 (4)
H170.27980.31990.65340.035*
C180.36607 (14)0.31032 (10)0.9088 (3)0.0324 (4)
H180.37090.26140.90530.039*
C190.41288 (14)0.34674 (10)1.0645 (3)0.0329 (4)
H190.44940.32301.16800.039*
C200.40569 (14)0.41784 (10)1.0669 (3)0.0335 (4)
H200.43760.44301.17310.040*
C210.35245 (14)0.45329 (9)0.9163 (2)0.0297 (4)
H220.34830.50230.92000.036*
O10.43553 (9)0.64763 (7)0.52482 (18)0.0359 (3)
O20.25800 (9)0.65642 (6)0.74180 (16)0.0258 (3)
H2o0.3204 (16)0.6532 (10)0.697 (3)0.031*
O30.23287 (9)0.52361 (6)0.64562 (15)0.0276 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0325 (9)0.0287 (10)0.0232 (8)0.0023 (7)0.0020 (7)0.0027 (7)
C20.0291 (9)0.0303 (10)0.0269 (8)0.0007 (7)0.0043 (7)0.0043 (7)
C30.0324 (10)0.0370 (11)0.0402 (10)0.0025 (8)0.0085 (8)0.0044 (8)
C40.0307 (9)0.0360 (11)0.0383 (10)0.0055 (8)0.0045 (8)0.0030 (8)
C50.0284 (9)0.0246 (9)0.0278 (8)0.0002 (7)0.0016 (7)0.0056 (7)
C60.0243 (8)0.0220 (8)0.0210 (7)0.0003 (6)0.0027 (6)0.0007 (6)
C70.0309 (9)0.0220 (8)0.0194 (7)0.0006 (7)0.0006 (6)0.0015 (6)
C80.0362 (10)0.0307 (10)0.0229 (8)0.0052 (8)0.0004 (7)0.0015 (7)
C90.0264 (8)0.0221 (8)0.0225 (7)0.0017 (6)0.0006 (6)0.0036 (6)
C100.0305 (9)0.0300 (10)0.0247 (8)0.0007 (7)0.0008 (7)0.0006 (7)
C110.0319 (9)0.0396 (11)0.0238 (8)0.0052 (8)0.0025 (7)0.0006 (7)
C120.0249 (9)0.0420 (11)0.0298 (9)0.0039 (8)0.0042 (7)0.0099 (8)
C130.0275 (9)0.0357 (10)0.0326 (9)0.0038 (8)0.0032 (7)0.0038 (8)
C140.0288 (9)0.0292 (9)0.0260 (8)0.0016 (7)0.0010 (7)0.0001 (7)
C150.0464 (11)0.0221 (9)0.0245 (8)0.0020 (8)0.0005 (8)0.0023 (7)
C160.0291 (9)0.0247 (9)0.0250 (8)0.0002 (7)0.0060 (7)0.0003 (7)
C170.0331 (9)0.0262 (9)0.0297 (9)0.0005 (7)0.0073 (7)0.0011 (7)
C180.0356 (10)0.0242 (9)0.0382 (10)0.0051 (7)0.0128 (8)0.0035 (8)
C190.0298 (9)0.0370 (11)0.0322 (9)0.0075 (8)0.0046 (7)0.0082 (8)
C200.0345 (10)0.0360 (11)0.0297 (9)0.0018 (8)0.0007 (7)0.0020 (8)
C210.0384 (10)0.0241 (9)0.0266 (8)0.0011 (7)0.0007 (7)0.0015 (7)
O10.0288 (7)0.0435 (8)0.0354 (7)0.0024 (6)0.0003 (5)0.0020 (6)
O20.0240 (6)0.0287 (7)0.0245 (6)0.0000 (5)0.0012 (5)0.0052 (5)
O30.0421 (7)0.0206 (6)0.0199 (5)0.0046 (5)0.0009 (5)0.0002 (4)
Geometric parameters (Å, º) top
C1—C41.527 (2)C10—C111.384 (2)
C1—C21.559 (2)C10—H100.9500
C1—C71.562 (2)C11—C121.386 (3)
C1—H11.0000C11—H110.9500
C2—C31.530 (3)C12—C131.381 (3)
C2—C51.537 (2)C12—H120.9500
C2—H21.0000C13—C141.387 (2)
C3—O11.441 (2)C13—H130.9500
C3—H3A0.9900C14—H140.9500
C3—H3B0.9900C15—O31.421 (2)
C4—O11.433 (2)C15—C161.511 (2)
C4—H4A0.9900C15—H15A0.9900
C4—H4B0.9900C15—H15B0.9900
C5—C61.534 (2)C16—C211.391 (2)
C5—H5A0.9900C16—C171.394 (2)
C5—H5B0.9900C17—C181.387 (3)
C6—O21.4387 (19)C17—H170.9500
C6—C91.521 (2)C18—C191.389 (3)
C6—C71.562 (2)C18—H180.9500
C7—O31.4305 (19)C19—C201.379 (3)
C7—C81.522 (2)C19—H190.9500
C8—H8A0.9800C20—C211.391 (2)
C8—H8B0.9800C20—H200.9500
C8—H8C0.9800C21—H220.9500
C9—C141.396 (2)O2—H2o0.87 (2)
C9—C101.397 (2)
C4—C1—C2103.32 (14)H8B—C8—H8C109.5
C4—C1—C7116.71 (14)C14—C9—C10117.94 (15)
C2—C1—C7105.08 (13)C14—C9—C6122.61 (15)
C4—C1—H1110.4C10—C9—C6119.45 (14)
C2—C1—H1110.4C11—C10—C9121.08 (16)
C7—C1—H1110.4C11—C10—H10119.5
C3—C2—C5114.28 (15)C9—C10—H10119.5
C3—C2—C1103.32 (14)C10—C11—C12120.28 (17)
C5—C2—C1106.17 (13)C10—C11—H11119.9
C3—C2—H2110.9C12—C11—H11119.9
C5—C2—H2110.9C13—C12—C11119.30 (16)
C1—C2—H2110.9C13—C12—H12120.3
O1—C3—C2105.82 (14)C11—C12—H12120.3
O1—C3—H3A110.6C12—C13—C14120.61 (17)
C2—C3—H3A110.6C12—C13—H13119.7
O1—C3—H3B110.6C14—C13—H13119.7
C2—C3—H3B110.6C13—C14—C9120.75 (16)
H3A—C3—H3B108.7C13—C14—H14119.6
O1—C4—C1106.40 (14)C9—C14—H14119.6
O1—C4—H4A110.4O3—C15—C16108.51 (13)
C1—C4—H4A110.4O3—C15—H15A110.0
O1—C4—H4B110.4C16—C15—H15A110.0
C1—C4—H4B110.4O3—C15—H15B110.0
H4A—C4—H4B108.6C16—C15—H15B110.0
C6—C5—C2106.29 (13)H15A—C15—H15B108.4
C6—C5—H5A110.5C21—C16—C17118.78 (16)
C2—C5—H5A110.5C21—C16—C15121.85 (15)
C6—C5—H5B110.5C17—C16—C15119.36 (15)
C2—C5—H5B110.5C18—C17—C16120.74 (17)
H5A—C5—H5B108.7C18—C17—H17119.6
O2—C6—C9104.83 (12)C16—C17—H17119.6
O2—C6—C5111.00 (13)C17—C18—C19120.17 (17)
C9—C6—C5114.90 (13)C17—C18—H18119.9
O2—C6—C7110.35 (12)C19—C18—H18119.9
C9—C6—C7114.54 (13)C20—C19—C18119.24 (16)
C5—C6—C7101.38 (12)C20—C19—H19120.4
O3—C7—C8111.68 (13)C18—C19—H19120.4
O3—C7—C6107.13 (12)C19—C20—C21120.97 (17)
C8—C7—C6111.09 (14)C19—C20—H20119.5
O3—C7—C1113.06 (13)C21—C20—H20119.5
C8—C7—C1109.21 (13)C20—C21—C16120.10 (16)
C6—C7—C1104.43 (13)C20—C21—H22120.0
C7—C8—H8A109.5C16—C21—H22120.0
C7—C8—H8B109.5C4—O1—C3103.87 (13)
H8A—C8—H8B109.5C6—O2—H2o108.4 (12)
C7—C8—H8C109.5C15—O3—C7116.08 (12)
H8A—C8—H8C109.5
C4—C1—C2—C30.84 (16)C5—C6—C9—C142.0 (2)
C7—C1—C2—C3123.68 (14)C7—C6—C9—C14114.80 (17)
C4—C1—C2—C5119.73 (14)O2—C6—C9—C1055.45 (18)
C7—C1—C2—C53.10 (17)C5—C6—C9—C10177.55 (15)
C5—C2—C3—O189.86 (17)C7—C6—C9—C1065.64 (19)
C1—C2—C3—O125.02 (17)C14—C9—C10—C111.7 (2)
C2—C1—C4—O123.80 (16)C6—C9—C10—C11178.76 (15)
C7—C1—C4—O190.94 (17)C9—C10—C11—C120.7 (3)
C3—C2—C5—C691.02 (17)C10—C11—C12—C130.8 (3)
C1—C2—C5—C622.18 (17)C11—C12—C13—C141.3 (3)
C2—C5—C6—O279.01 (16)C12—C13—C14—C90.3 (3)
C2—C5—C6—C9162.29 (13)C10—C9—C14—C131.2 (2)
C2—C5—C6—C738.20 (16)C6—C9—C14—C13179.27 (15)
O2—C6—C7—O342.19 (17)O3—C15—C16—C2113.3 (2)
C9—C6—C7—O375.80 (16)O3—C15—C16—C17167.77 (15)
C5—C6—C7—O3159.87 (12)C21—C16—C17—C180.6 (2)
O2—C6—C7—C8164.41 (13)C15—C16—C17—C18178.35 (16)
C9—C6—C7—C846.42 (17)C16—C17—C18—C190.7 (3)
C5—C6—C7—C877.91 (15)C17—C18—C19—C200.4 (3)
O2—C6—C7—C177.98 (15)C18—C19—C20—C210.0 (3)
C9—C6—C7—C1164.03 (13)C19—C20—C21—C160.1 (3)
C5—C6—C7—C139.70 (15)C17—C16—C21—C200.2 (2)
C4—C1—C7—O329.0 (2)C15—C16—C21—C20178.73 (16)
C2—C1—C7—O3142.74 (13)C1—C4—O1—C340.50 (17)
C4—C1—C7—C8153.99 (15)C2—C3—O1—C440.92 (17)
C2—C1—C7—C892.26 (16)C16—C15—O3—C7162.70 (13)
C4—C1—C7—C687.11 (17)C8—C7—O3—C1552.94 (19)
C2—C1—C7—C626.63 (16)C6—C7—O3—C15174.79 (14)
O2—C6—C9—C14124.12 (16)C1—C7—O3—C1570.71 (18)
Hydrogen-bond geometry (Å, º) top
Cg4 is the centroid of the C16–C21 ring.
D—H···AD—HH···AD···AD—H···A
O2—H2o···O10.87 (2)1.93 (2)2.7794 (17)162.9 (18)
C10—H10···O30.952.563.091 (2)116
C5—H5A···O2i0.992.583.266 (2)126
C19—H19···O1ii0.952.583.344 (2)138
C12—H12···Cg4iii0.952.743.6619 (19)165
Symmetry codes: (i) x, y+3/2, z1/2; (ii) x+1, y+1, z+2; (iii) x, y+1, z+2.
(III) (±)-(1aR,1bS,4aR,5S,5aR)-5-Benzyloxy-5-methyl-5a-phenylhexahydro-2H-oxireno[2',3':3,4]cyclopenta[1,2-c]furan top
Crystal data top
C21H22O3Dx = 1.291 Mg m3
Mr = 322.39Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121Cell parameters from 2191 reflections
a = 5.6392 (2) Åθ = 2.9–27.5°
b = 11.0427 (5) ŵ = 0.09 mm1
c = 26.6311 (13) ÅT = 120 K
V = 1658.37 (13) Å3Block, colourless
Z = 40.34 × 0.14 × 0.04 mm
F(000) = 688
Data collection top
Nonius KappaCCD
diffractometer
1867 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tubeRint = 0.073
Graphite monochromatorθmax = 27.5°, θmin = 2.9°
ω scansh = 77
12562 measured reflectionsk = 1410
2221 independent reflectionsl = 3334
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)] = 0.123H-atom parameters constrained
wR(F2) = 0.279 w = 1/[σ2(Fo2) + (0.P)2 + 10.5966P]
where P = (Fo2 + 2Fc2)/3
S = 1.17(Δ/σ)max = 0.001
2221 reflectionsΔρmax = 0.40 e Å3
190 parametersΔρmin = 0.44 e Å3
0 restraintsExtinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.027 (5)
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 > 2sigma(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)
C10.6868 (17)0.6626 (7)0.1385 (3)0.032 (2)
H10.82550.65330.16150.038*
C20.7362 (19)0.7660 (7)0.1007 (3)0.035 (2)
H20.91010.77630.09470.042*
C30.631 (2)0.8762 (7)0.1259 (4)0.045 (3)
H3A0.74780.91480.14840.054*
H3B0.57930.93630.10050.054*
C40.471 (2)0.7092 (8)0.1684 (3)0.041 (2)
H4A0.32890.65960.16080.049*
H4B0.50240.70420.20490.049*
C50.6092 (14)0.7235 (7)0.0536 (3)0.0232 (16)
H50.64900.76080.02040.028*
C60.5563 (14)0.5938 (7)0.0566 (3)0.0247 (17)
C70.6606 (15)0.5476 (7)0.1061 (3)0.0230 (16)
C80.9005 (16)0.4920 (7)0.0942 (3)0.0301 (18)
H8A0.98490.47460.12550.045*
H8B0.99370.54900.07400.045*
H8C0.87780.41670.07530.045*
C90.5260 (13)0.5131 (7)0.0124 (3)0.0210 (15)
C100.3788 (15)0.4124 (7)0.0148 (3)0.0298 (18)
H100.29650.39510.04510.036*
C110.3498 (17)0.3360 (8)0.0267 (3)0.036 (2)
H110.24950.26710.02450.043*
C120.4673 (19)0.3614 (8)0.0704 (3)0.038 (2)
H120.45260.30880.09850.046*
C130.606 (2)0.4624 (9)0.0735 (3)0.060 (4)
H130.67990.48240.10440.072*
C140.639 (2)0.5365 (9)0.0319 (3)0.046 (3)
H140.74200.60430.03430.055*
C150.5820 (19)0.4029 (9)0.1723 (3)0.042 (2)
H15A0.72560.35570.16380.050*
H15B0.62800.46540.19720.050*
C17A0.232 (3)0.3698 (9)0.2235 (6)0.030 (6)*0.54 (3)
H17A0.22150.45380.23090.035*0.54 (3)
C18A0.062 (2)0.2904 (12)0.2423 (5)0.038 (5)*0.54 (3)
H18A0.06370.32010.26250.045*0.54 (3)
C19A0.077 (3)0.1675 (12)0.2315 (5)0.034 (4)*0.54 (3)
H19A0.03890.11320.24430.041*0.54 (3)
C20A0.261 (3)0.1240 (9)0.2019 (4)0.032 (5)*0.54 (3)
H20A0.27110.03990.19450.038*0.54 (3)
C21A0.431 (3)0.2033 (11)0.1831 (4)0.037 (5)*0.54 (3)
H21A0.55640.17360.16280.045*0.54 (3)
C16A0.416 (2)0.3262 (10)0.1939 (6)0.026 (5)*0.54 (3)
C17B0.226 (3)0.3804 (10)0.2286 (7)0.035 (8)*0.46 (3)
H17B0.25370.46290.23690.043*0.46 (3)
C18B0.040 (3)0.3181 (13)0.2510 (6)0.035 (5)*0.46 (3)
H18B0.06000.35810.27460.042*0.46 (3)
C19B0.001 (3)0.1974 (14)0.2390 (5)0.030 (5)*0.46 (3)
H19B0.12850.15490.25430.036*0.46 (3)
C20B0.145 (4)0.1390 (10)0.2046 (5)0.034 (5)*0.46 (3)
H20B0.11670.05650.19630.041*0.46 (3)
C21B0.331 (4)0.2012 (13)0.1822 (5)0.029 (5)*0.46 (3)
H21B0.43040.16120.15860.035*0.46 (3)
C16B0.372 (3)0.3219 (13)0.1942 (7)0.032 (6)*0.46 (3)
O10.4314 (16)0.8325 (6)0.1539 (2)0.057 (2)
O20.3649 (10)0.6835 (5)0.0638 (2)0.0279 (13)
O30.4946 (11)0.4616 (5)0.12770 (19)0.0301 (13)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.043 (5)0.025 (4)0.027 (4)0.011 (4)0.011 (4)0.004 (3)
C20.046 (6)0.025 (4)0.033 (4)0.014 (4)0.003 (4)0.006 (3)
C30.072 (8)0.020 (4)0.043 (5)0.010 (5)0.014 (6)0.003 (4)
C40.060 (6)0.037 (5)0.026 (4)0.023 (5)0.007 (4)0.001 (4)
C50.018 (4)0.027 (4)0.025 (4)0.002 (3)0.003 (3)0.003 (3)
C60.021 (4)0.031 (4)0.023 (3)0.013 (3)0.000 (3)0.006 (3)
C70.025 (4)0.019 (3)0.025 (3)0.004 (3)0.005 (3)0.000 (3)
C80.028 (4)0.024 (4)0.038 (4)0.005 (4)0.005 (4)0.005 (3)
C90.017 (3)0.024 (4)0.022 (3)0.003 (3)0.004 (3)0.004 (3)
C100.017 (4)0.026 (4)0.046 (4)0.000 (3)0.012 (4)0.000 (4)
C110.033 (5)0.025 (4)0.049 (5)0.003 (4)0.004 (4)0.006 (4)
C120.058 (6)0.028 (4)0.028 (4)0.015 (5)0.003 (4)0.007 (3)
C130.094 (10)0.052 (6)0.034 (5)0.041 (7)0.024 (6)0.014 (4)
C140.059 (7)0.054 (6)0.025 (4)0.041 (6)0.013 (4)0.007 (4)
C150.042 (6)0.051 (5)0.032 (4)0.005 (5)0.001 (4)0.020 (4)
O10.084 (6)0.044 (4)0.042 (4)0.033 (4)0.013 (4)0.003 (3)
O20.021 (3)0.035 (3)0.028 (3)0.007 (3)0.006 (2)0.004 (2)
O30.033 (3)0.031 (3)0.026 (3)0.009 (3)0.001 (3)0.007 (2)
Geometric parameters (Å, º) top
C1—C71.542 (10)C12—H120.9500
C1—C41.545 (13)C13—C141.390 (11)
C1—C21.547 (11)C13—H130.9500
C1—H11.0000C14—H140.9500
C2—C31.512 (11)C15—C16A1.387 (13)
C2—C51.519 (11)C15—O31.441 (9)
C2—H21.0000C15—C16B1.596 (15)
C3—O11.432 (14)C15—H15A0.9900
C3—H3A0.9900C15—H15B0.9900
C3—H3B0.9900C17A—C18A1.3900
C4—O11.433 (10)C17A—C16A1.3900
C4—H4A0.9900C17A—H17A0.9500
C4—H4B0.9900C18A—C19A1.3900
C5—C61.465 (11)C18A—H18A0.9500
C5—O21.472 (9)C19A—C20A1.3900
C5—H51.0000C19A—H19A0.9500
C6—O21.477 (9)C20A—C21A1.3900
C6—C91.487 (10)C20A—H20A0.9500
C6—C71.532 (10)C21A—C16A1.3900
C7—O31.452 (10)C21A—H21A0.9500
C7—C81.519 (11)C17B—C18B1.3900
C8—H8A0.9800C17B—C16B1.3900
C8—H8B0.9800C17B—H17B0.9500
C8—H8C0.9800C18B—C19B1.3900
C9—C141.364 (10)C18B—H18B0.9500
C9—C101.389 (10)C19B—C20B1.3900
C10—C111.399 (11)C19B—H19B0.9500
C10—H100.9500C20B—C21B1.3900
C11—C121.370 (12)C20B—H20B0.9500
C11—H110.9500C21B—C16B1.3900
C12—C131.364 (13)C21B—H21B0.9500
C7—C1—C4119.2 (8)C13—C12—H12120.2
C7—C1—C2105.2 (6)C11—C12—H12120.2
C4—C1—C2103.4 (7)C12—C13—C14120.8 (9)
C7—C1—H1109.5C12—C13—H13119.6
C4—C1—H1109.5C14—C13—H13119.6
C2—C1—H1109.5C9—C14—C13120.9 (8)
C3—C2—C5115.4 (8)C9—C14—H14119.5
C3—C2—C1103.6 (7)C13—C14—H14119.5
C5—C2—C1102.9 (7)C16A—C15—O3112.6 (10)
C3—C2—H2111.4C16A—C15—C16B5.6 (12)
C5—C2—H2111.4O3—C15—C16B107.4 (10)
C1—C2—H2111.4C16A—C15—H15A109.1
O1—C3—C2105.6 (7)O3—C15—H15A109.1
O1—C3—H3A110.6C16B—C15—H15A113.4
C2—C3—H3A110.6C16A—C15—H15B109.1
O1—C3—H3B110.6O3—C15—H15B109.1
C2—C3—H3B110.6C16B—C15—H15B110.0
H3A—C3—H3B108.8H15A—C15—H15B107.8
O1—C4—C1107.4 (8)C18A—C17A—C16A120.0
O1—C4—H4A110.2C18A—C17A—H17A120.0
C1—C4—H4A110.2C16A—C17A—H17A120.0
O1—C4—H4B110.2C19A—C18A—C17A120.0
C1—C4—H4B110.2C19A—C18A—H18A120.0
H4A—C4—H4B108.5C17A—C18A—H18A120.0
C6—C5—O260.4 (5)C18A—C19A—C20A120.0
C6—C5—C2110.7 (7)C18A—C19A—H19A120.0
O2—C5—C2112.4 (7)C20A—C19A—H19A120.0
C6—C5—H5119.8C21A—C20A—C19A120.0
O2—C5—H5119.8C21A—C20A—H20A120.0
C2—C5—H5119.8C19A—C20A—H20A120.0
C5—C6—O260.1 (5)C20A—C21A—C16A120.0
C5—C6—C9124.5 (7)C20A—C21A—H21A120.0
O2—C6—C9114.9 (6)C16A—C21A—H21A120.0
C5—C6—C7107.1 (7)C15—C16A—C21A118.0 (9)
O2—C6—C7113.1 (6)C15—C16A—C17A121.9 (9)
C9—C6—C7121.7 (6)C21A—C16A—C17A120.0
O3—C7—C8113.2 (6)C18B—C17B—C16B120.0
O3—C7—C6108.2 (6)C18B—C17B—H17B120.0
C8—C7—C6107.3 (6)C16B—C17B—H17B120.0
O3—C7—C1112.3 (6)C19B—C18B—C17B120.0
C8—C7—C1111.3 (7)C19B—C18B—H18B120.0
C6—C7—C1104.1 (6)C17B—C18B—H18B120.0
C7—C8—H8A109.5C18B—C19B—C20B120.0
C7—C8—H8B109.5C18B—C19B—H19B120.0
H8A—C8—H8B109.5C20B—C19B—H19B120.0
C7—C8—H8C109.5C21B—C20B—C19B120.0
H8A—C8—H8C109.5C21B—C20B—H20B120.0
H8B—C8—H8C109.5C19B—C20B—H20B120.0
C14—C9—C10118.0 (7)C20B—C21B—C16B120.0
C14—C9—C6121.1 (7)C20B—C21B—H21B120.0
C10—C9—C6120.8 (7)C16B—C21B—H21B120.0
C9—C10—C11121.1 (8)C21B—C16B—C17B120.0
C9—C10—H10119.5C21B—C16B—C15125.2 (10)
C11—C10—H10119.5C17B—C16B—C15114.8 (10)
C12—C11—C10119.4 (8)C3—O1—C4109.9 (8)
C12—C11—H11120.3C5—O2—C659.5 (5)
C10—C11—H11120.3C15—O3—C7113.6 (7)
C13—C12—C11119.6 (8)
C7—C1—C2—C3149.9 (8)C9—C10—C11—C120.4 (14)
C4—C1—C2—C324.2 (10)C10—C11—C12—C131.8 (15)
C7—C1—C2—C529.3 (9)C11—C12—C13—C143.5 (18)
C4—C1—C2—C596.4 (8)C10—C9—C14—C130.7 (16)
C5—C2—C3—O179.5 (9)C6—C9—C14—C13178.4 (10)
C1—C2—C3—O132.2 (10)C12—C13—C14—C93.0 (19)
C7—C1—C4—O1124.4 (8)C16A—C17A—C18A—C19A0.0
C2—C1—C4—O18.2 (9)C17A—C18A—C19A—C20A0.0
C3—C2—C5—C6128.9 (8)C18A—C19A—C20A—C21A0.0
C1—C2—C5—C616.8 (9)C19A—C20A—C21A—C16A0.0
C3—C2—C5—O263.5 (10)O3—C15—C16A—C21A97.6 (11)
C1—C2—C5—O248.6 (8)C16B—C15—C16A—C21A118 (11)
C2—C5—C6—O2104.7 (7)O3—C15—C16A—C17A79.3 (11)
O2—C5—C6—C9101.2 (8)C16B—C15—C16A—C17A59 (11)
C2—C5—C6—C9154.1 (8)C20A—C21A—C16A—C15176.9 (13)
O2—C5—C6—C7107.2 (6)C20A—C21A—C16A—C17A0.0
C2—C5—C6—C72.5 (9)C18A—C17A—C16A—C15176.8 (13)
C5—C6—C7—O3140.5 (6)C18A—C17A—C16A—C21A0.0
O2—C6—C7—O376.3 (8)C16B—C17B—C18B—C19B0.0
C9—C6—C7—O367.0 (9)C17B—C18B—C19B—C20B0.0
C5—C6—C7—C897.2 (7)C18B—C19B—C20B—C21B0.0
O2—C6—C7—C8161.3 (6)C19B—C20B—C21B—C16B0.0
C9—C6—C7—C855.4 (9)C20B—C21B—C16B—C17B0.0
C5—C6—C7—C120.9 (8)C20B—C21B—C16B—C15178.5 (15)
O2—C6—C7—C143.2 (9)C18B—C17B—C16B—C21B0.0
C9—C6—C7—C1173.5 (7)C18B—C17B—C16B—C15178.6 (14)
C4—C1—C7—O332.7 (9)C16A—C15—C16B—C21B69 (11)
C2—C1—C7—O3148.0 (7)O3—C15—C16B—C21B90.9 (13)
C4—C1—C7—C8160.7 (7)C16A—C15—C16B—C17B109 (11)
C2—C1—C7—C884.0 (8)O3—C15—C16B—C17B90.5 (10)
C4—C1—C7—C684.0 (8)C2—C3—O1—C428.3 (10)
C2—C1—C7—C631.2 (9)C1—C4—O1—C312.3 (10)
C5—C6—C9—C1428.5 (13)C2—C5—O2—C6101.8 (7)
O2—C6—C9—C1498.1 (10)C9—C6—O2—C5116.9 (8)
C7—C6—C9—C14119.2 (10)C7—C6—O2—C597.1 (7)
C5—C6—C9—C10150.6 (8)C16A—C15—O3—C7176.7 (9)
O2—C6—C9—C1081.0 (9)C16B—C15—O3—C7174.6 (8)
C7—C6—C9—C1061.7 (11)C8—C7—O3—C1556.0 (8)
C14—C9—C10—C110.9 (13)C6—C7—O3—C15174.7 (6)
C6—C9—C10—C11179.9 (8)C1—C7—O3—C1571.1 (8)
Hydrogen-bond geometry (Å, º) top
Cg6 is the centroid of the C16a–C21a ring.
D—H···AD—HH···AD···AD—H···A
C10—H10···O30.952.573.124 (10)117
C8—H8B···O2i0.982.583.462 (10)150
C14—H14···O2ii0.952.573.450 (11)155
C4—H4B···Cg6iii0.992.653.569 (10)154
Symmetry codes: (i) x+1, y, z; (ii) x+1/2, y+3/2, z; (iii) x+1, y+1/2, z+1/2.
 

Acknowledgements

We thank the EPSRC National Crystallography Service (University of Southampton) for the data collections.

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