Hydroxylamine → HCID 178494171, compound

Participants

Reaction Steps

A solution of (3E)-4-(4-tert-butylphenyl)-4-(5-chloro-6-methoxypyridin-2-yl)but-3-enenitrile obtained in Reference Example 4-13 (101 mg) in isopropanol (3 mL) was stirred at 105° C., during which a 50% hydroxylamine solution (0.1 mL) was added dropwise thereto. The mixture was stirred at the same temperature for two hours. The reaction solution was left to cool and then the solvent was evaporated under reduced pressure. Carbonyldiimidazole (72 mg) was added to a solution of the residue in 1,4-dioxane (3 mL), and the mixture was stirred at 120° C. for 30 minutes. Carbonyldiimidazole (55 mg) was further added and the mixture was stirred at 140° C. for 30 minutes. The reaction solution was left to cool and then water was added, followed by extraction with ethyl acetate. The organic layer was washed with brine, dried over sodium sulfate and filtered, after which the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (chloroform:methanol=10:0→9:1) to give 3-[(2E)-3-(4-tert-butylphenyl)-3-(5-chloro-6-methoxypyridin-2-yl)prop-2-en-1-yl]-1,2,4-oxadiazol-5(2H)-one as an orange oil (73 mg, 62%).

Provenance & Evidence