p-Toluenesulfonic acid monohydrate → HCID 178497267, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of methyl 6-formyl-2-naphthalenecarboxylate (227 mg, 1.06 mmol) obtained in example 3 (2), (2R,3R)-2-(2,4-difluorophenyl)-3-[[1-(hydroxymethyl)-2-hydroxyethyl]thio]-1-(1H-1,2,4-triazol-1-yl)-2-butanol (381 mg, 1.06 mmol) and p-toluenesulfonic acid monohydrate (363 mg, 1.91 mmol) in anhydrous tetrahydrofuran (50 ml) was concentrated at room temperature using a rotary evaporator under reduced pressure and then using a vacuum pump. A solution of the residue in anhydrous tetrahydrofuran (40 ml) was concentrated according to the procedure described above. The same procedure was repeated twice. A solution of the resulting residue in tetrahydrofuran (50 ml) was poured into a saturated aqueous sodium hydrogencarbonate solution cooled to 0° C. with stirring. The mixture was extracted with ethyl acetate and the organic layer was washed with aqueous sodium chloride solution, dried over anhydrous magnesium sulfate and then concentrated under reduced pressure. The oily residue was chromatographed on a silica gel column using ethyl acetate-hexane (1:2) as the eluant to afford methyl 6-[trans-5-[((1R,2R)-2-(2,4-difluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]thio]-1,3-dioxan-2-yl]-2-naphthalenecarboxylate (trans isomer, 331 mg, yield 56%) as a white solid, and then using ethyl acetate-hexane (3:1) as the eluant to afford methyl 6-[cis-5-[[(1R,2R)-2-(2,4-difluorophenyl)-2-hydroxy-1-methyl-3-(1H-1,2,4-triazol-1-yl)propyl]thio]-1,3-dioxan-2-yl]-2-naphthalenecarboxylate (cis isomer, 77 mg, yield 14%) as a colorless oil. The trans isomer was recrystallized from ethyl acetate-hexane to give white fluffy crystals.

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