反应详情

2-Amino-4,5-difluorobenzoic acid (0.5 g), 2,6-difluorobenzoyl chloride (0.80 mL) and triethyl amine/toluene (1/1) (18 mL) were reacted as described under (10). Reaction time 1 day. Extraction between ethyl acetate (20 mL) and HCl (2N,20 mL), followed by separation of the organic toluene and precipitated with hexane. The resulting mixture was further purified on a silicagel column using dichloromethane as eluent. The isolated fraction identified as 2-(2,6-difluoro-phenyl)-6,7-difluoro-benzo[d][1,3]oxazin-4-one (0.71 g), mp. 165 C, MS m/e: 295 M+.

1. customReaction time 1 day
2. extractionExtraction between ethyl acetate (20 mL) and HCl (2N,20 mL)
3. customfollowed by separation of the organic toluene
4. customprecipitated with hexane
5. customThe resulting mixture was further purified on a silicagel column