Application of 450-91-9, These common heterocyclic compound, 450-91-9, name is 4-Fluoro-2-methoxyaniline, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route.
Step b: Compound 1a2 (8.0 g, 43 mmol) was added into a 500 ml reaction flask, and concentrated sulfuric acid (100 ml) was added to dissolve the substrate under constant agitation. At -20 C., concentrated nitric acid (6.15 ml, 48 mmol) was slowly added dropwise with stirring, and the reaction mixture was stirred for 5 mins at this temperature. The reaction progress was monitored by TLC. After completion of the reaction, the mixture was poured into ice water. Sodium hydroxide/water solution (150 ml/300 ml) were added slowly to the reaction system at -20 C. in an ice-water bath, and the mixture was adjusted to pH 8-9. The reaction solution was extracted with EA/water system for three times, the organic layer was separated, washed with water, saturated brine, dried over anhydrous Na2SO4, and concentrated under reduced pressure to give compound 1a (8.7 g) which was used directly in the next reaction. Yield: 80%; purity: 100%; MS m/z (ESI): 187.0 [M+H]+; 1H NMR (400 MHz, DMSO-d6): delta 7.34 (d, J=7.8 Hz, 1H), 7.04 (d, J=13.4 Hz, 1H), 5.25 (brs, 2H), 3.90 (s, 3H).
Statistics shows that 4-Fluoro-2-methoxyaniline is playing an increasingly important role. we look forward to future research findings about 450-91-9.