反应详情

A solution of 2-chloro-3-oxobutyramide (1 g) in acetic anhydride (5 ml) containing acetyl chloride (1 ml) was heated in a 100° oil bath for 2 hours. Excess reagent was evaporated under reduced pressure and the residue was vacuum distilled in a kugelrohr apparatus. The distilled product crystallized to give a colorless solid with mp 54°-8°; ir (Nujol) 3200 and 1700 cm-1 (broad); nmr (CDCl2) 2.28 (CH3), 2.47 (CH3), 5.53 (CH), and 9.7 ppm (NH), (a weaker set of singlets corresponding to the enol appears at 2.23, 2.52, and 8.7 ppm); mass spectrum m/e 43 (100%), 93, 135, and 177 (M+).

1. temperaturewas heated in a 100° oil bath for 2 hours
2. customExcess reagent was evaporated under reduced pressure
3. distillationdistilled in a kugelrohr apparatus
4. customThe distilled product crystallized
5. customto give a colorless solid with mp 54°-8°