Water → Ethyl 5-(2,5-dimethoxybenzyl)-1,2,4-oxadiazole-3-carboxylate

関与物質

反応手順

2-(2,5-dimethoxyphenyl)acetyl chloride (0.662 mL; 3.78 mmol) was added to a mixture of ethyl 2-amino-2-(hydroxyimino)acetate (0.500 g; 3.78 mmol) and N,N diisopropylethylamine (1.05 mL; 6.06 mmol) in dichloromethane (18 mL) at −15° C. The reaction mixture was stirred at room temperature overnight and poured into a mixture of ice and water. The formed precipitate was filtered off, suspended in pyridine (18 mL) and refluxed in a sealed tube for 20 h and concentrated under reduced pressure. The crude material was purified by flash chromatography on silica (eluent 20 to 100% ethyl acetate in heptane) to yield 0.414 g (37%) of ethyl 5-(2,5-dimethoxybenzyl)-1,2,4-oxadiazole-3-carboxylate as a yellow oil.

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