反应详情

温度

3 °C

2,4-Dinitroaniline (3.7 g, 0.02 mol) is suspended in a mixture of acetic acid (20 ml) and propionic acid (10 ml) and cooled to 3° C. 40% (w/w) nitrosyl sulfuric acid in sulfuric acid (6.4 g, 0.02 mol) is added dropwise and stirring continued for 30 minutes to give a pale yellow solution. Crude 2,5-bis(2-ethylhexyloxy)aniline (0.02 mol) solution is diluted with IMS (200 ml) and 10% sulfamic acid solution (20 ml) added, followed by ice (200 g). The above pale yellow diazonium salt solution is slowly added with stirring and a dark oil rapidly separated. The mixture is stirred overnight and the water is decanted off. The crude product (8.3 g) is dissolved in 25/75 dichloromethane/hexane and purified over silica gel, the required product eluting with 50/50 hexane/dichloromethane. Evaporation and trituration with methanol gave 4-((2,4-dinitrophenyl)diazenyl)-2,5-bis(2-ethylhexyloxy)-aniline as a violet-blue crystalline solid (4.2 g, 39%).

1. customto give a pale yellow solution
2. additionadded
3. stirringwith stirring
4. customa dark oil rapidly separated
5. stirringThe mixture is stirred overnight
6. customthe water is decanted off
7. dissolutionThe crude product (8.3 g) is dissolved in 25/75 dichloromethane/hexane
8. custompurified over silica gel
9. washthe required product eluting with 50/50 hexane/dichloromethane
10. customEvaporation and trituration with methanol