反应 #1884953

反应方程式

4-methylaminobenzoic acid

5-methoxy-2-aminothiophenol

K2CO3

→

6-Methoxy-2-(4-methylaminophenyl)benzothiazole

收率 22.3%

反应条件

后处理

1. 1
   温度The reaction mixture was then cooled to room temperature
2. 2
   过滤The precipitate was filtered under reduced pressure
3. 3
   其他The crude product was re-crystallized twice from acetone/water and THF/water

实验过程

A mixture of 4-methylaminobenzoic acid (11.5 g, 76.2 mmol) and 5-methoxy-2-aminothiophenol (12.5, g, 80 mmol) was heated in PPA (˜30 g) to 170° C. under N2 atmosphere for 1.5 hr. The reaction mixture was then cooled to room temperature and poured into 10% K2CO3 solution. The precipitate was filtered under reduced pressure. The crude product was re-crystallized twice from acetone/water and THF/water followed by the treatment with active with carbon to give 4.6 g (21%) of 6-Methoxy-2-(4-methylaminophenyl)benzothiazole as a yellow solid. 1HNMR (300 MHz, acetone-d6) δ: 7.84(d, J=8.7 Hz, 2H, H-2′6′), 7.78(dd, J1=8.8 Hz, J2=1.3 Hz, 1H, H-4), 7.52(d, J=2.4 Hz, 1H, H-7), 7.05(dd, J1=8.8 Hz, J2=2.4 Hz, H-5), 6.70(d, J=7.6 Hz, 2H, H-3′5′), 5.62(s, 1H, NH), 3.88(s, 3H, OCH3), 2.85(d, J=6.2 Hz, 3H, NCH3)

来源