A solution of [
3R*,
4R*,
5S*,
6S*]-3,4-epoxy-1,7-dioxaspiro[5.5]undecan-5-ol (
1) (561 mg, 3.01mmol) in dry tetrahydrofuran (30 ml) under a nitrogen atmosphere was cooled to 0 deg.C in an ice/water bath. Lithium aluminium hydride (4.52 ml, of a 1 mol L
-1 solution in THF, 4.52 mmol) was added in 3 portions over 1 minute, and the reaction mixture allowed to stir at 0 deg.C for 1 h then room temperature for 12 h. After quenching with sodium dihydrogen phosphate solution (10 ml, 10% w/v), the reaction mixture was extracted with ethyl acetate (3x 50 ml), the combined extracts washed with water (10 ml) and dried over sodium sulphate. Removal of the solvent under reduced pressure gave a colourless oil, which was purified by flash chromatography using hexane-ethyl acetate (2:1) as eluent to afford [4R*,5R*,6S*]-1,7-Dioxaspiro[5.5]undecane-4,5-diol (
2) (310 mg, 55%) as colourless needles [
1].
M.p. 135-137 deg.C.
IR (Nujol) cm-1 3600-3150 (br, s, OH), 1082 (s, C-O).
1H-NMR (400 MHz, CDCl3) 1.47 (1H, ddd, J11ax,11eq 13.3, J11ax,10ax 13.3 and J11ax,10eq 4.4 Hz, 11ax-H), 1.54-1.81 (5H, m, 9-CH2, 10-CH2 and 3ax-H), 1.90 (1H, dt, J11eq,11ax 13.3 and J11eq,10 2.6 Hz, 11eq-H), 2.05-2.14 (1H, m, 3eq-H), 3.41 (1H, dd, J5,4 7.4 and J5,OH 3.7 Hz, 5-H), 3.62 (1H, ddd, J2eq, 2ax 11.8, J2eq,3ax 5.5 and J2eq,3eq 2.3 Hz, 2eq-H), 3.71-3.99 (6H, m, 8-CH2, 4-H, 2ax-H, 4-OH and 5-OH).
13C-NMR (100 MHz, CDCl3) 17.6, 24.8, 27.6, 30.6 (CH2, C-3, C-9, C-10 and C-11), 55.6 (CH2, C-2), 61.3 (CH2, C-8), 68.6 (CH, C-4), 71.1 (CH, C-5), 98.4 (quat, C-6).
CI-MS 189 (M+H, 85%), 171 (M+H-H2O, 100), 153 (10), 118 (13), 115 (8), 101 (80), 83 (10).
Anal. calc. for C9H16O4 C, 57.44; H, 8.57%; M+H, 189.1127, found C, 57.50; H, 8.42%; M+H (CI, NH3), 189.1134.