[N+:1]([O-:4])(O)=[O:2].[Br:5][C:6]1[CH:11]=[C:10]([F:12])[CH:9]=[CH:8][C:7]=1[CH2:13][C:14]([OH:16])=[O:15]>>[Br:5][C:6]1[CH:11]=[C:10]([F:12])[C:9]([N+:1]([O-:4])=[O:2])=[CH:8][C:7]=1[CH2:13][C:14]([OH:16])=[O:15]To stirring fuming HNO3 (15 mL) at −15° C. was added 2-bromo-4-fluorophenylacetic acid (10 g, 43 mmol) in portions such that the internal temperature remained below −10° C. After completing the addition the reaction was stirred with warming to +5° C. over 15 min. The mixture was poured onto ice (500 g). Product separated as a slightly sticky solid which on manipulation with a spatula became powdery. The suspension was stirred vigorously until the ice had completely melted. While still very cold, the solids were collected by filtration, rinsed very well with H2O (1 L). The solid was dried under vacuum to afford 2-(2-bromo-4-fluoro-5-nitrophenyl)acetic acid (6.04 g, 51% yield) as a pale yellow solid which was used as is in the next reaction.
Wird geladen…