organic compounds
(3S,4S,5R)-4-Hydroxy-3-methyl-5-[(2S,3R)-3-methylpent-4-en-2-yl]-4,5-dihydrofuran-2(3H)-one
aFakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Strasse 6, 44221 Dortmund, Germany, and bFachbereich Chemie, Universität Duisburg-Essen, Campus Essen UniversitätsStrasse 7, 45117 Essen, Germany
*Correspondence e-mail: hans.preut@udo.edu
The 11H18O3, was corroborated by single-crystal X-ray In the crystal, molecules are linked via a O—H⋯O hydrogen bond and a chain of molecules is formed along [010].
of the title compound, CRelated literature
For further synthetic details, see: Abraham, Körner & Hiersemann (2004); Abraham, Körner et al. (2004); Evans et al. (1981, 1999); Körner & Hiersemann (2006, 2007); Mitsunobu (1981); Mitsunobu & Yamada (1967); Mitsunobu et al. (1967); Otera et al. (1992); Pollex & Hiersemann (2005).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: APEX2 (Bruker, 2004); cell SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003).
Supporting information
10.1107/S1600536808042414/hb2861sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808042414/hb2861Isup2.hkl
The title compound, (I), was synthesized from the corresponding syn-aldol adduct, (II), using tetrabutylammonium fluoride (TBAF) in the presence of acetic acid (Otera et al., 1992) for the removal of the silyl protecting group. The subsequent lactonization proceeded in situ.
To a solution of diastereomerically pure (II) (66 mg, 0.15 mmol, 1.0 eq) in tetrahydrofuran (0.8 ml) was added acetic acid (0.9 µl, 0.015 mmol, 0.1 eq) in tetrahydrofuran (0.1 ml) and TBAF (1 M in tetrahydrofuran, 0.225 ml, 1.5 eq) at 273 K. After stirring for 20 min at 273 K, the mixture was allowed to warm to room temperature. After stirring the reaction mixture for 4.5 h at room temperature, the reaction was quenched by the addition of sat. aqueous NH4Cl solution. The phases were separated, and the aqueous phase was extracted with CH2Cl2 (3 × 5 ml). The combined organic layers were dried (MgSO4) and concentrated under reduced pressure. Flash δ): 0.92 (d, J = 6.8 Hz, 3H), 1.05 (d, J = 6.8 Hz, 3H), 1.31 (d, J = 7.1 Hz, 3H), 1.73 (dqd, J = 6.8, 6.8, 3.6 Hz, 1H), 2.14 (br. s, 1 H), 2.33 (apparent sex, J = 7.7 Hz, 1H), 2.59 (dq, J = 8.6, 7.1 Hz, 1H), 3.91 (dd, J = 8.6 Hz, 1H), 4.20 (dd, J = 8.6, 3.6 Hz, 1H), 5.04 (d, 3J(Z) = 10.0 Hz, 1H), 5.05 (d, 3J(E) = 17.8 Hz, 1H), 5.73 (ddd, 3J(E) = 17.8 Hz, 3J(Z) = 10.0 Hz, 3J = 7.7 Hz, 1H); 13C NMR (CDCl3, 100 MHz, δ): 10.7 (CH3), 12.8 (CH3), 17.2 (CH3), 39.4 (CH), 41.0 (CH), 44.2 (CH), 77.2 (CH), 85.2 (CH), 115.1 (CH2), 143.0 (CH), 176.7 (C); IR (cm-1): 3405(br,s) (ν O—H, OH in H-bridges), 3090(w) 3005(w) (ν C—H, olefin), 2965(s) 2935(m) 2900(m) 2855(w) (νas,s C—H, CH2, CH3, CH), 1740(s) (ν C=O, lactone), 1640(w) (ν C=C), 1460(s) (δas C—H, CH3, CH2), 1380(s) (δs C—H, CH3); Anal. Calcd. for C11H18O3: C, 66.6; H, 9.2; Found: C, 66.7; H, 9.3; [α]D20 +61.4 (c 0.487, CHCl3).
(isohexane/ethyl acetate 20/1 to 10/1 to 5/1) afforded (I) as a single diastereomer in quantitative yield (29.6 mg, 0.15 mmol) as colourless crystals. Colourless needles of (I) were obtained by vapor diffusion recrystallization technique from isohexane and ethyl acetate: mp 361 K; Rf 0.35 (cyclohexane/ethyl acetate 2/1); 1H NMR (CDCl3, 400 MHz,The H atoms were geometrically placed (C—H = 0.95–1.00Å, O—H = 0.84Å) and refined as riding with Uiso(H) = 1.2Ueq(C,O) or 1.5Ueq(methyl C).
Data collection: APEX2 (Bruker, 2004); cell
SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL-Plus (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).Fig. 1. : The molecular structure of (I) with displacement ellipsoids for the non-hydrogen atoms shown at the 30% probability level. |
C11H18O3 | F(000) = 216 |
Mr = 198.25 | Dx = 1.163 Mg m−3 |
Monoclinic, P21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2yb | Cell parameters from 1365 reflections |
a = 7.604 (2) Å | θ = 2.7–26.3° |
b = 6.574 (2) Å | µ = 0.08 mm−1 |
c = 11.323 (4) Å | T = 173 K |
β = 91.211 (7)° | Needle, colourless |
V = 565.9 (3) Å3 | 0.35 × 0.10 × 0.07 mm |
Z = 2 |
Siemens SMART three-axis goniometer with APEXII area-detector system diffractometer | 1076 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.131 |
Graphite monochromator | θmax = 28.3°, θmin = 1.8° |
Detector resolution: 512 pixels mm-1 | h = −9→10 |
Data collection strategy APEX 2/COSMO scans | k = −8→8 |
7868 measured reflections | l = −15→14 |
1507 independent reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.054 | H-atom parameters constrained |
wR(F2) = 0.098 | w = 1/[σ2(Fo2) + (0.0279P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.98 | (Δ/σ)max < 0.001 |
1507 reflections | Δρmax = 0.19 e Å−3 |
132 parameters | Δρmin = −0.19 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.077 (11) |
C11H18O3 | V = 565.9 (3) Å3 |
Mr = 198.25 | Z = 2 |
Monoclinic, P21 | Mo Kα radiation |
a = 7.604 (2) Å | µ = 0.08 mm−1 |
b = 6.574 (2) Å | T = 173 K |
c = 11.323 (4) Å | 0.35 × 0.10 × 0.07 mm |
β = 91.211 (7)° |
Siemens SMART three-axis goniometer with APEXII area-detector system diffractometer | 1076 reflections with I > 2σ(I) |
7868 measured reflections | Rint = 0.131 |
1507 independent reflections |
R[F2 > 2σ(F2)] = 0.054 | 1 restraint |
wR(F2) = 0.098 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.19 e Å−3 |
1507 reflections | Δρmin = −0.19 e Å−3 |
132 parameters |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.2255 (2) | 0.2085 (3) | 0.91883 (16) | 0.0351 (5) | |
O2 | 0.1493 (2) | 0.7353 (3) | 0.96072 (16) | 0.0382 (5) | |
H2 | 0.2076 | 0.8318 | 0.9904 | 0.057* | |
O3 | 0.2839 (2) | 0.0670 (3) | 1.09375 (17) | 0.0408 (5) | |
C1 | 0.3186 (5) | 0.7143 (7) | 0.4846 (3) | 0.0700 (11) | |
H1A | 0.1994 | 0.7345 | 0.4607 | 0.084* | |
H1B | 0.4096 | 0.7302 | 0.4292 | 0.084* | |
C2 | 0.3570 (4) | 0.6651 (5) | 0.5929 (3) | 0.0471 (8) | |
H2A | 0.4783 | 0.6469 | 0.6118 | 0.057* | |
C3 | 0.2316 (4) | 0.6337 (4) | 0.6919 (2) | 0.0381 (7) | |
H3 | 0.2615 | 0.7378 | 0.7535 | 0.046* | |
C4 | 0.2658 (4) | 0.4224 (4) | 0.7492 (2) | 0.0352 (7) | |
H4 | 0.3959 | 0.4082 | 0.7615 | 0.042* | |
C5 | 0.1827 (3) | 0.4084 (4) | 0.8699 (2) | 0.0305 (6) | |
H5 | 0.0522 | 0.4226 | 0.8610 | 0.037* | |
C6 | 0.2512 (3) | 0.5554 (4) | 0.9651 (2) | 0.0309 (6) | |
H6 | 0.3778 | 0.5877 | 0.9522 | 0.037* | |
C7 | 0.2319 (4) | 0.4339 (4) | 1.0786 (2) | 0.0324 (6) | |
H7 | 0.1086 | 0.4522 | 1.1059 | 0.039* | |
C8 | 0.2500 (3) | 0.2207 (4) | 1.0367 (2) | 0.0327 (6) | |
C9 | 0.0401 (4) | 0.6683 (5) | 0.6558 (3) | 0.0513 (8) | |
H9A | 0.0246 | 0.8089 | 0.6288 | 0.077* | |
H9B | −0.0348 | 0.6434 | 0.7236 | 0.077* | |
H9C | 0.0072 | 0.5748 | 0.5916 | 0.077* | |
C10 | 0.2046 (4) | 0.2460 (5) | 0.6698 (3) | 0.0468 (8) | |
H10A | 0.2487 | 0.1173 | 0.7025 | 0.070* | |
H10B | 0.2503 | 0.2650 | 0.5902 | 0.070* | |
H10C | 0.0758 | 0.2429 | 0.6657 | 0.070* | |
C11 | 0.3561 (4) | 0.4916 (5) | 1.1806 (3) | 0.0477 (8) | |
H11A | 0.3352 | 0.4020 | 1.2481 | 0.071* | |
H11B | 0.3347 | 0.6331 | 1.2035 | 0.071* | |
H11C | 0.4781 | 0.4767 | 1.1558 | 0.071* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0416 (11) | 0.0232 (11) | 0.0406 (11) | 0.0024 (9) | 0.0034 (8) | −0.0022 (8) |
O2 | 0.0413 (11) | 0.0230 (10) | 0.0504 (12) | 0.0052 (9) | 0.0008 (9) | −0.0046 (9) |
O3 | 0.0428 (12) | 0.0276 (11) | 0.0520 (13) | 0.0029 (9) | 0.0009 (10) | 0.0033 (9) |
C1 | 0.078 (2) | 0.083 (3) | 0.050 (2) | −0.008 (2) | 0.0124 (17) | 0.006 (2) |
C2 | 0.0516 (19) | 0.0459 (19) | 0.0439 (19) | −0.0065 (15) | 0.0038 (15) | −0.0007 (14) |
C3 | 0.0457 (18) | 0.0296 (15) | 0.0391 (17) | −0.0013 (13) | 0.0026 (14) | −0.0019 (12) |
C4 | 0.0367 (16) | 0.0273 (15) | 0.0418 (16) | 0.0022 (13) | 0.0027 (12) | −0.0043 (13) |
C5 | 0.0327 (14) | 0.0184 (13) | 0.0403 (16) | −0.0005 (12) | 0.0005 (12) | −0.0025 (12) |
C6 | 0.0294 (15) | 0.0194 (14) | 0.0441 (16) | −0.0010 (11) | 0.0024 (12) | −0.0012 (12) |
C7 | 0.0328 (15) | 0.0250 (14) | 0.0396 (16) | −0.0016 (12) | 0.0010 (12) | −0.0060 (12) |
C8 | 0.0275 (14) | 0.0268 (14) | 0.0440 (17) | −0.0030 (12) | 0.0027 (12) | −0.0020 (14) |
C9 | 0.057 (2) | 0.0446 (19) | 0.0527 (19) | 0.0102 (16) | 0.0027 (15) | 0.0093 (14) |
C10 | 0.066 (2) | 0.0294 (16) | 0.0447 (17) | 0.0034 (16) | −0.0029 (15) | −0.0096 (14) |
C11 | 0.054 (2) | 0.0397 (17) | 0.0489 (19) | −0.0075 (15) | −0.0091 (15) | 0.0000 (14) |
O1—C8 | 1.347 (3) | C5—C6 | 1.531 (4) |
O1—C5 | 1.460 (3) | C5—H5 | 1.0000 |
O2—C6 | 1.414 (3) | C6—C7 | 1.522 (4) |
O2—H2 | 0.8400 | C6—H6 | 1.0000 |
O3—C8 | 1.223 (3) | C7—C8 | 1.487 (4) |
C1—C2 | 1.296 (4) | C7—C11 | 1.524 (4) |
C1—H1A | 0.9500 | C7—H7 | 1.0000 |
C1—H1B | 0.9500 | C9—H9A | 0.9800 |
C2—C3 | 1.501 (4) | C9—H9B | 0.9800 |
C2—H2A | 0.9500 | C9—H9C | 0.9800 |
C3—C9 | 1.521 (4) | C10—H10A | 0.9800 |
C3—C4 | 1.553 (4) | C10—H10B | 0.9800 |
C3—H3 | 1.0000 | C10—H10C | 0.9800 |
C4—C5 | 1.520 (4) | C11—H11A | 0.9800 |
C4—C10 | 1.534 (4) | C11—H11B | 0.9800 |
C4—H4 | 1.0000 | C11—H11C | 0.9800 |
C8—O1—C5 | 110.4 (2) | C7—C6—H6 | 110.2 |
C6—O2—H2 | 109.5 | C5—C6—H6 | 110.2 |
C2—C1—H1A | 120.0 | C8—C7—C6 | 102.4 (2) |
C2—C1—H1B | 120.0 | C8—C7—C11 | 114.6 (2) |
H1A—C1—H1B | 120.0 | C6—C7—C11 | 116.1 (2) |
C1—C2—C3 | 127.4 (3) | C8—C7—H7 | 107.8 |
C1—C2—H2A | 116.3 | C6—C7—H7 | 107.8 |
C3—C2—H2A | 116.3 | C11—C7—H7 | 107.8 |
C2—C3—C9 | 113.5 (2) | O3—C8—O1 | 119.8 (3) |
C2—C3—C4 | 109.4 (2) | O3—C8—C7 | 129.1 (2) |
C9—C3—C4 | 113.4 (2) | O1—C8—C7 | 111.1 (2) |
C2—C3—H3 | 106.7 | C3—C9—H9A | 109.5 |
C9—C3—H3 | 106.7 | C3—C9—H9B | 109.5 |
C4—C3—H3 | 106.7 | H9A—C9—H9B | 109.5 |
C5—C4—C10 | 110.8 (2) | C3—C9—H9C | 109.5 |
C5—C4—C3 | 111.1 (2) | H9A—C9—H9C | 109.5 |
C10—C4—C3 | 112.7 (2) | H9B—C9—H9C | 109.5 |
C5—C4—H4 | 107.3 | C4—C10—H10A | 109.5 |
C10—C4—H4 | 107.3 | C4—C10—H10B | 109.5 |
C3—C4—H4 | 107.3 | H10A—C10—H10B | 109.5 |
O1—C5—C4 | 107.56 (19) | C4—C10—H10C | 109.5 |
O1—C5—C6 | 103.3 (2) | H10A—C10—H10C | 109.5 |
C4—C5—C6 | 117.0 (2) | H10B—C10—H10C | 109.5 |
O1—C5—H5 | 109.5 | C7—C11—H11A | 109.5 |
C4—C5—H5 | 109.5 | C7—C11—H11B | 109.5 |
C6—C5—H5 | 109.5 | H11A—C11—H11B | 109.5 |
O2—C6—C7 | 113.9 (2) | C7—C11—H11C | 109.5 |
O2—C6—C5 | 109.0 (2) | H11A—C11—H11C | 109.5 |
C7—C6—C5 | 103.1 (2) | H11B—C11—H11C | 109.5 |
O2—C6—H6 | 110.2 | ||
C1—C2—C3—C9 | −0.8 (5) | C4—C5—C6—O2 | 90.6 (3) |
C1—C2—C3—C4 | 126.9 (4) | O1—C5—C6—C7 | −30.1 (2) |
C2—C3—C4—C5 | 163.2 (2) | C4—C5—C6—C7 | −148.1 (2) |
C9—C3—C4—C5 | −69.1 (3) | O2—C6—C7—C8 | 146.5 (2) |
C2—C3—C4—C10 | −71.8 (3) | C5—C6—C7—C8 | 28.6 (3) |
C9—C3—C4—C10 | 55.9 (3) | O2—C6—C7—C11 | −88.0 (3) |
C8—O1—C5—C4 | 144.9 (2) | C5—C6—C7—C11 | 154.1 (2) |
C8—O1—C5—C6 | 20.6 (2) | C5—O1—C8—O3 | 178.6 (2) |
C10—C4—C5—O1 | 55.7 (3) | C5—O1—C8—C7 | −2.0 (3) |
C3—C4—C5—O1 | −178.3 (2) | C6—C7—C8—O3 | 161.8 (3) |
C10—C4—C5—C6 | 171.3 (2) | C11—C7—C8—O3 | 35.3 (4) |
C3—C4—C5—C6 | −62.6 (3) | C6—C7—C8—O1 | −17.5 (3) |
O1—C5—C6—O2 | −151.49 (19) | C11—C7—C8—O1 | −144.0 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O3i | 0.84 | 2.02 | 2.830 (3) | 163 |
Symmetry code: (i) x, y+1, z. |
Experimental details
Crystal data | |
Chemical formula | C11H18O3 |
Mr | 198.25 |
Crystal system, space group | Monoclinic, P21 |
Temperature (K) | 173 |
a, b, c (Å) | 7.604 (2), 6.574 (2), 11.323 (4) |
β (°) | 91.211 (7) |
V (Å3) | 565.9 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.35 × 0.10 × 0.07 |
Data collection | |
Diffractometer | Siemens SMART three-axis goniometer with APEXII area-detector system diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7868, 1507, 1076 |
Rint | 0.131 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.054, 0.098, 0.98 |
No. of reflections | 1507 |
No. of parameters | 132 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.19, −0.19 |
Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXTL-Plus (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2003).
D—H···A | D—H | H···A | D···A | D—H···A |
O2—H2···O3i | 0.84 | 2.02 | 2.830 (3) | 163 |
Symmetry code: (i) x, y+1, z. |
References
Abraham, L., Körner, M. & Hiersemann, M. (2004). Tetrahedron Lett. 45, 3647–3650. Web of Science CrossRef CAS Google Scholar
Abraham, L., Körner, M., Schwab, P. & Hiersemann, M. (2004). Adv. Synth. Catal. 346, 1281–1294. Web of Science CSD CrossRef CAS Google Scholar
Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Evans, D. A., Bartroli, J. & Shih, T. L. (1981). J. Am. Chem. Soc. 103, 2127–2129. CrossRef CAS Web of Science Google Scholar
Evans, D. A., Miller, S. J., Lectka, T. & Matt, V. P. (1999). J. Am. Chem. Soc. 121, 7559–7573. Web of Science CrossRef CAS Google Scholar
Körner, M. & Hiersemann, M. (2006). Synlett, pp. 121–123. Google Scholar
Körner, M. & Hiersemann, M. (2007). Org. Lett. 9, 4979–4982. Web of Science PubMed Google Scholar
Mitsunobu, O. (1981). Synthesis, pp. 1–28. CrossRef Web of Science Google Scholar
Mitsunobu, O. & Yamada, M. (1967). Bull. Chem. Soc. Jpn, 40, 2380–2382. CrossRef CAS Web of Science Google Scholar
Mitsunobu, O., Yamada, M. & Mukaiyama, T. (1967). Bull. Chem. Soc. Jpn, 40, 935–939. CrossRef CAS Web of Science Google Scholar
Otera, J., Niibo, Y. & Nozaki, H. (1992). Tetrahedron Lett. 33, 3655–3658. CrossRef CAS Web of Science Google Scholar
Pollex, A. & Hiersemann, M. (2005). Org. Lett. 7, 5705–5708. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2003). J. Appl. Cryst. 36, 7–13. Web of Science CrossRef CAS IUCr Journals Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The title compound, (I), was synthesized using a catalytic asymmetric Claisen rearrangement (Abraham, Körner et al., 2004; Abraham, Körner & Hiersemann, 2004; Pollex & Hiersemann, 2005; Körner & Hiersemann, 2006, 2007), a diastereoselective reduction with K-Selectride (Körner & Hiersemann, 2006, 2007), a Mitsunobu reaction (Mitsunobu & Yamada, 1967; Mitsunobu et al., 1967; Mitsunobu, 1981) and an Evans aldol addition (Evans et al., 1981). In order to verify the relative configuration of the obtained aldol adduct, 4-(tert-butyldimethylsilyloxy)-3-hydroxy-2,5,6-trimethyloct-7-enoyl)-4-isopropyloxazolidin-2-one, (II), a γ-lactone, (I), was prepared by removal of the silyl protecting group (Otera et al., 1992) and subsequent in situ lactonization. Fig. 1 depicts the structure of the isolated diastereomer (I). The configuration of the chiral C atoms in (I) can be attributed to the stereochemical course of the Evans aldol addition (C3 S and C4 S), the diastereoselective reduction with K-Selectride (C5 S) followed by Mitsunobu reaction (C5 R), and the catalytic asymmetric Claisen rearrangement (C[2] S and C[3] R) using the chiral Lewis acid [Cu{(S,S)-tert-Butyl-box}](H2O)2(SbF6)2 (Evans et al., 1999).
In the crystal, an O—H···O hydrogen bond (Table 1) links the molecules into chains propagating in [010].