HCID 25209257, compound → HCID 24875829, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of benzyl 7-[(1R,2R,3R)-2-(4,4-difluoro-3-oxooctyl)-5-oxo-3-(2-tetrahydropyranyloxy) cyclopentyl]heptanoate (1) (39.84 g, 70.54 mmol) in tetrahydrofuran (40 ml), acetic acid (260 ml) and water (140 ml) were added. The mixture was stirred at about 40° C. for 4 hours. The reaction was concentrated under reduced pressure and the residue was purified by silica gel column chromatography (Fuji Silysia BW-300 1600 g, ethyl acetate:hexane=1:3). Fractions containing impurities were purified again by silica gel column chromatography (Fuji Silysia FL-60D 1600 g, ethyl acetate:hexane=1:4). Fractions still containing impurities were collected and further purified repeatedly with silica gel column chromatography (Fuji Silysia FL-60D 1000 g, IPA:hexane=8:100), (Fuji Silysia FL-60D 1600 g, IPA:hexane=7.5:100→3:40), (Fuji Silysia FL-60D 1600 g, IPA:hexane=3:40). Fractions containing substantially no impurities were collected and evaporated to give benzyl 7-[(2R,4aR,5R,7aR)-2-(1,1-difluoropentyl)-2-hydroxy-6-oxooctahydrocyclopenta[b]pyran-5-yl]heptanate (2) (25.68 g, 53.44 mmol, yield: 75.8%).

Provenance & Evidence