反应 #162551

反应方程式

water

1-chloro-3-fluoro-2-nitrobenzene

2-aminobutyric acid

K2CO3

→

2-((3-chloro-2-nitrophenyl)amino)butanoic acid

收率 96.7%

溶剂

DMSO

反应条件

后处理

1. 1
   其他went up to 110° C.
2. 2
   温度After cooling to rt
3. 3
   洗涤The aq. layer was washed with methyl tert-butyl ether (2×5 L)
4. 4
   其他to remove organic impurities
5. 5
   其他to give an orange solid
6. 6
   过滤The orange solid was collected by filtration
7. 7
   洗涤washed with water (2×4 L)
8. 8
   其他air-dried

实验过程

A mixture of 1-chloro-3-fluoro-2-nitrobenzene (2.00 Kg, 11.4 mol), 2-aminobutyric acid (1.22 kg, 11.8 mol) and K2CO3 (1.58 Kg, 11.4 mol) in anhydrous DMSO (4.2 L) was heated at 80° C. for 16 h (after the reaction initiated, the internal temperature went up to 110° C.). At this time LC-MS analysis showed that the reaction was complete. After cooling to rt, the reaction mixture was carefully poured into water (10 L) with vigorous stirring. The aq. layer was washed with methyl tert-butyl ether (2×5 L) to remove organic impurities. The aq. layer was then acidified to pH ˜1.5 with cond HCl to give an orange solid. The orange solid was collected by filtration, washed with water (2×4 L) and air-dried to give 2-((3-chloro-2-nitrophenyl)amino)butanoic acid (2.85 Kg), which was used as such in the next step. 1H NMR (DMSO-d6) δ ppm 7.35 (t, J=8.3 Hz, 1H), 6.82-6.91 (m, 2H), 6.25 (d, J=7.6 Hz, 1H), 4.14 (td, J=7.4, 5.4 Hz, 1H), 3.4 (br. s., 1H), 1.74-1.92 (m, 2H), 0.88 (t, J=7.4 Hz, 3H). Mass Spectrum (ESI) m/z=259.2 (M+1).

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