Hydrochloric Acid → 2-(2,4-Difluorophenyl)-3-mercapto-1-(1H-1,2,4-triazol-1-yl)-2-butanol

Beteiligte Stoffe

Reaktionsschritte

A solution of (2R,3S)-2-(2,4-difluorophenyl)-3-methyl-2-[(1H-1,2,4-triazol-1-yl)methyl]oxirane (0.40 g), methyl 3-mercaptopropionate (1.42 ml) and 28% sodium methylate methanolic solution (1.25 ml) in methanol (10 ml) was refluxed for 4.5 hours in an oil bath under heating. To the reaction mixture was added methyl 3-mercaptopropionate (0.53 ml, 0.32 ml) respectively after 2 hours and 3.5 hours of heating. Further, 28% sodium methylate-methanol solution (0.63 ml) was added after 2.5 hours. After 4.5 hours, the reaction mixture was cooled, neutralized with 1N hydrochloric acid (9.6 ml) and extracted with dichloromethane (100 ml). The extract was washed with saturated saline (20 ml), dried over anhydrous sodium sulfate and distilled off the solvent under reduced pressure. The residue was subjected to a silica gel column chromatography (hexane:ethyl acetate=1:3) for purification. The objective fractions were concentrated. Then, the collected precipitate was washed with isopropyl ether to afford (2R, 3R)-2-(2,4-difluorophenyl )-3-mercapto-1-(1-H-1,2,4-triazol-1-yl)-2-butanol (0.22 g) as colorless needles.

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