反应详情

温度

-2 °C

4-Nitrobenzyl bromide (64.22 g), 4-amino-1,2,4-triazole (26 g) and isopropyl alcohol (586 ml) were stirred together at reflux for 71/2 hours. The isopropanol solvent was replaced with water by using an azeotropic distillation procedure, in vacuo, on a Buchi rotary evaporator. The volume of the final aqueous slurry was 750 ml. 675 ml of this slurry was cooled to -2° C. and hydrochloric acid (50.8 ml, 12 M) added over a few minutes. A solution of sodium nitrite (21.7 g) in water (86 ml) was then added dropwise, and subsurface over a 40 minute period. The temperature of the batch was kept between -2° and -1° C. during the addition and then allowed to warm to 18° C. over 30 minutes. The temperature was then increased to 28° C. and held for 1 hour and the solution treated with charcoal (4.5 g, Fisons) for 15 minutes. The charcoal was removed and the filtrate (750 ml) divided equally in two. One half of the solution was made basic with ammonia solution (22 ml) and the precipitated base collected, washed with water (2×30 ml) and dried (16 hours at 35° C. in vacuo). This gave an 83.3% yield (22.73 g) of 1-(4-nitrobenzyl)-1,2,4-triazole.

1. temperatureat reflux for 71/2 hours
2. distillationan azeotropic distillation procedure
3. customin vacuo, on a Buchi rotary evaporator
4. additionhydrochloric acid (50.8 ml, 12 M) added over a few minutes
5. additionA solution of sodium nitrite (21.7 g) in water (86 ml) was then added dropwise
6. additionThe temperature of the batch was kept between -2° and -1° C. during the addition
7. temperatureto warm to 18° C. over 30 minutes
8. temperatureThe temperature was then increased to 28° C.
9. waitheld for 1 hour
10. additionthe solution treated with charcoal (4.5 g, Fisons) for 15 minutes
11. customThe charcoal was removed
12. customthe precipitated base collected
13. washwashed with water (2×30 ml)
14. customdried (16 hours at 35° C. in vacuo)