反应详情

A solution of crude ethyl 4-(3-chlorophenyl)-2,4-dioxobutanoate (max 294 g, 1.16 mol) and hydroxylamine hydrochloride (120.4 g, 1.73 mol) in ethanol (4 L) was heated at 80° C. for 4 h. After cooling (over night) to ca 5-10° C., the mixture was filtered, washed with cold ethanol and dried in vacuo to afford the title compound (214.5 g, 74%). 1H NMR: 7.82 (s, 1H), 7.72 (m, 1H), 7.47 (m, 2H), 4.03 (s, 3H). MS (M++1)=252.

1. temperatureAfter cooling (over night) to ca 5-10° C.
2. filtrationthe mixture was filtered
3. washwashed with cold ethanol
4. customdried in vacuo