Acetonitrile → (3aR,4R,5R,6aS)-Hexahydro-5-hydroxy-4-[(3R)-5-phenyl-3-[(tetrahydro-2H-pyran-2-yl)oxy]pentyl]-2H-cyclopenta[b]furan-2-ol

Participants

Reaction Steps

A 1.5 M solution of Diisobutylaluminum hydride in toluene (46.0 g, 69 mmol) was added dropwise to a stirred solution of compound [9a] (17.0 g, 30 mmol) in toluene (500 mL) at −20-−10° C. The mixture was stirred for 1 hour at the same temperature. Methanol (200 mL) was added dropwise to the stirred mixture at −20-−10° C. The obtained mixture was stirred for 1 hour at room temperature, filtered and evaporated under reduced pressure. Dichloromethane (250 mL) was added to the residue. The resulting solution was washed with brine (2×220 mL), dried over sodium sulfate, filtered and evaporated under reduced pressure. To complete hydrolysis of p-phenylbenzoate-groups a mixture of the residue and potassium carbonate (10:0 g) in methanol (100 mL) was stirred at room temperature for 7 hours (TLC monitoring). The mixture was evaporated under reduced pressure. A mixture of the residue, dichloromethane (300 mL) and water (300 mL) was stirred for 10 min at room temperature. The organic layer was separated, washed with brine, dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by column chromatography on silica gel exane/ethyl acetate 1:2 v/v) to obtain 10.3 g of the compound [11a] (88% yield), [α]D20 −53.5° (c 1.0, MeCN). 1H NMR (CDCl3) δ: 7.10-7.29 (m, 5H); 5.47-5.63 (m, 1H); 4.57-4.69 (m, 2H); 3.69-3.94 (m, 2H); 3.60-3.75 (m, 1H); 3.40-3.55 (m, 1H). 13C NMR (CDCl3) δ: 19.9; 25.4; 29.0; 31.2; 31.9; 36.6; 40.2; 41.5; 42.5; 46.4; 48.0; 55.3; 55.6; 62.8; 79.4; 79.9; 82.4; 86.4; 97.6; 100.0; 101.1; 125.6; 128.2; 128.3; 142.5. IR (neat): 3398, 2944, 2867, 1451 cm−1.

Provenance & Evidence