p-Toluenesulfonic acid monohydrate → (2R, 3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1,2,4-triazol-1-yl)butan-2-ol p-toluenesulfonate

Participants

Reaction Conditions

Reaction Steps

There was dissolved 17.59 g (70 mmol) of (2R,3S)-2-(2,4-difluorophenyl)-3-methyl-2-[(1H-1,2,4-triazol-1-yl)methyl]oxirane in 113 g of an aqueous solution of 4-methylenepiperidine (content: 61%) and the obtained solution was refluxed with heating at 90° C. for 21 hours. After the reaction, an excess of 4-methylenepiperidine was removed under reduced pressure, and the residue was dissolved in 140 ml of isopropyl alcohol and thereto was added 13.32 g (70 mmol) of p-toluenesulfonic acid monohydrate dissolved in 50 ml of isopropyl alcohol. The obtained mixture was allowed to stand for 1 hour at room temperature and overnight in a refrigerator, and then the precipitated crystal was separated by filtration and washed with 50 ml of isopropyl alcohol and dried to obtain 32.20 g of (2R,3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1,2,4-triazol-1-yl)butan-2-ol p-toluenesulfonate in a form of a crystal.

Provenance & Evidence