反应详情

208 g of a 50% aqueous hydroxylamine solution and 91 ml of 28% aqueous ammonia were added to 350 ml of water, into which 348 g of methyl acetoacetate was dropped over 50 minutes at temperature below 15° C. After the completion of the dropping, the reaction solution returned to room temperature and stood undisturbed for 6 days to give 900 ml of an aqueous solution of crude ammonium salt of 5 -hydroxy-3-methyl-4-(3-methylisooxazol-5-yl)isoxazole.

1. additionwas dropped over 50 minutes at temperature below 15° C
2. customreturned to room temperature