Benzenesulfonic acid, 4-methyl-, compd. with pyridine (1:1) → (2R,3R)-2-(2,4-Difluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-2,3-butanediol

Participants

Reaction Conditions

Reaction Steps

In ethanol (50 ml) were dissolved (3R)-2-(2,4-difluorophenyl)-3-(3,4,5,6-tetrahydro-2H-pyran-2-yl)oxy-1-(1H-1,2,4-triazol-1-yl)-2-butanol (4.4 g) and pyridinium p-toluenesulfonate (0.93 g). The solution was stirred for two hours at 55° C. to which was further added pyridinium p-toluenesulfonate (0.20 g), followed by stirring for further two hours at 55° C. The reaction mixture was cooled, then the solvent was distilled off. To the residue was added ethyl acetate (250 ml), which was washed with water (50 ml) and a saturated aqueous solution of sodium chloride (50 ml) successively. The ethyl acetate layer was dried over anhydrous magnesium sulfate, then the solvent was distilled off under reduced pressure. To the residue was added ethyl ether, then precipitating crystals were collected by filtration to give (2R,3R)-2-(2,4-difluorophenyl)-1-(1H-1,2,4-triazol-1-yl)-2,3-butanediol (1.37 g). m.p. 115°-117° C. [α]D =-80.3° C. (c=1.0 in methanol)

Provenance & Evidence