反应详情

To stirring fuming HNO3 (90.00 wt %, 30.0 ml, 45 g, 643 mmol, 7.21 eq) at −15° C. was added 4-fluoro-2-methylphenylacetic acid (15.00 g, 89.2 mmol, 1.00 eq) 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 (400 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 and dried on the filter to afford crude 2-(4-fluoro-2-methyl-5-nitrophenyl)acetic acid (18.43 g, 97% yield) as a pale yellow solid which was used as is in the next reaction. 1H NMR (400 MHz, acetone-d6): δ 8.06 (d, J=7.6 Hz, 1H), 7.36 (d, J=12.0 Hz), 3.84 (s, 2H), 2.44 (s, 3H)

1. customremained below −10° C
2. additionthe addition the reaction
3. temperaturewith warming to +5° C. over 15 min
4. additionThe mixture was poured onto ice (400 g)
5. customProduct separated as a slightly sticky solid which on manipulation with a spatula
6. stirringThe suspension was stirred vigorously until the ice
7. filtrationWhile still very cold, the solids were collected by filtration
8. washrinsed very well with H2O
9. customdried on the
10. filtrationfilter