反应详情

温度

95 °C

A mixture of platinum on carbon (sulfided) catalyst (5.3 kg of Engelhard C3759), formic acid (86.8 kg) and water (28.4 L) is heated to about 95° C. A mixture of 2-amino-4-methyl-3,5-dinitrobenzonitrile (5) (10.9 kg), formic acid (28 kg) and water (8 L) is then added to the catalyst-containing solution over about 45 minutes, while maintaining the temperature of the catalyst-containing mixture at about 95° C. The vessel that formerly contained the initial 2-amino-4-methyl-3,5-dinitrobenzonitrile/water/formic acid mixture is then rinsed with water (5.5 L) and the rinse solution is added to the catalyst-containing mixture. The resultant catalyst-containing mixture is then agitated at about 95° C. for about 30 minutes. After the mixture is cooled to about 35-45° C., the mixture is filtered to remove the catalyst and the filtered catalyst is washed with 96% formic acid (32.3 kg). The combined product-containing filtrate is placed under vacuum and heated (from about 25° C. to about 60° C.), and formic acid/water is distilled off, until about 98.4 kg of distillate is collected. At this point, methanol (109.1 kg) is added to the product-containing mixture. The mixture is gradually cooled to about 5° C., over a period of about 1 hour, and held at this temperature for about 1 hour. The mixture is then filtered and the product filter cake is washed with methanol (42.5 kg). The product is then dried in a vacuum tray dryer, at a temperature of about 45-50° C. and a vacuum of about 70 torr until dry to obtain 6-(Formylamino)-7-methyl-1H-benzimidazole-4-carbonitrile (9) (6.4 kg, 65% yield).

1. additionis then added to the catalyst-containing solution over about 45 minutes
2. temperaturewhile maintaining the temperature of the catalyst-containing mixture at about 95° C
3. washis then rinsed with water (5.5 L)
4. additionthe rinse solution is added to the catalyst-containing mixture
5. additionThe resultant catalyst-containing mixture
6. temperatureAfter the mixture is cooled to about 35-45° C.
7. filtrationthe mixture is filtered
8. customto remove the catalyst
9. washthe filtered catalyst is washed with 96% formic acid (32.3 kg)
10. additionThe combined product-containing filtrate
11. temperatureheated (from about 25° C. to about 60° C.), and formic acid/water
12. distillationis distilled off, until about 98.4 kg of distillate
13. customis collected
14. additionAt this point, methanol (109.1 kg) is added to the product-containing mixture
15. temperatureThe mixture is gradually cooled to about 5° C., over a period of about 1 hour
16. waitheld at this temperature for about 1 hour
17. filtrationThe mixture is then filtered
18. filtrationthe product filter cake
19. washis washed with methanol (42.5 kg)
20. customThe product is then dried in a vacuum tray dryer, at a temperature of about 45-50° C.
21. customa vacuum of about 70 torr until dry