反应详情

A mixture of 3-{[3-methoxy-4-(5-methyl-2-phenyl-1,3-oxazol-4-ylmethoxy)benzyl]oxy}-1-phenyl-1H-pyrazole-5-carbaldehyde (990 mg), hydroxylamine hydrochloride (200 mg), pyridine (1 mL) and ethanol (10 mL) was refluxed for 3 hrs. After concentration of the reaction mixture, dilute hydrochloric acid was added to the residue, and the mixture was extracted with ethyl acetate. The ethyl acetate layer was washed with saturated brine, dried over anhydrous magnesium sulfate and concentrated. The residue was dissolved in acetic anhydride (20 mL), and the mixture was refluxed for 5 hrs. After concentration of the reaction mixture, The residue was subjected to silica gel column chromatography to give 3-{[3-methoxy-4-(5-methyl-2-phenyl-1,3-oxazol-4-ylmethoxy)benzyl]oxy}-1-phenyl-1H-pyrazole-5-carbonitrile (850 mg, yield 86%) as colorless crystals from a fraction eluted with ethyl acetate-hexane (1:2, v/v). The crystals were recrystallized from tetrahydrofuran-hexane. melting point: 120-121° C.

1. temperaturewas refluxed for 3 hrs
2. extractionthe mixture was extracted with ethyl acetate
3. washThe ethyl acetate layer was washed with saturated brine
4. dry with materialdried over anhydrous magnesium sulfate
5. concentrationconcentrated
6. dissolutionThe residue was dissolved in acetic anhydride (20 mL)
7. temperaturethe mixture was refluxed for 5 hrs