反应详情

温度

90 °C

3-(5-Pyridin-2-yl-2H-tetrazol-2-yl)benzonitrile (300 mg, 1.21 mmol), sodium azide (86.5 mg, 1.33 mmol) and zinc bromide (272 mg, 1.21 mmol) were suspended in water (3 mL). The reaction was capped with a reflux condenser and stirred at 90° C. for 24 h, after which time it was cooled to rt and HCl 3N (1.5 mL) and ethyl acetate (20 mL) were added and the mixture stirred vigorously until no solid was left. The organic layer was isolated and aqueous layer extracted with ethyl acetate (2×20 mL). The combined organic layers were evaporated, 10 mL of 0.25N NaOH was added, the mixture was stirred for 30min, until the original precipitate was dissolved and a suspension of zinc hydroxide was formed. The suspension was filtered, and the solid washed with 10 ml 1 N NaOH. To the filtrate was added 2 mL of 3N HCl with stirring causing the tetrazole to precipitate. The tetrazole was filtered and washed with 5 mL of 3N HCl and dried in vacuo to afford white powder. 1H NMR (CD3OD, 500 MHz) δ 8.91 (s, 1H), 8.83 (d, 1H), 8.41 (d, 1H), 8.32-8.25 (m, 2H), 8.09 (t, 1H), 7.95 (t, 1H), 7.64 (t, 1H). MS 292.1 (M+H)+.

1. customThe reaction was capped with a reflux condenser
2. temperatureafter which time it was cooled to rt
3. stirringthe mixture stirred vigorously until no solid
4. waitwas left
5. customThe organic layer was isolated
6. extractionaqueous layer extracted with ethyl acetate (2×20 mL)
7. customThe combined organic layers were evaporated
8. addition10 mL of 0.25N NaOH was added
9. stirringthe mixture was stirred for 30min, until the original precipitate
10. dissolutionwas dissolved
11. additiona suspension of zinc hydroxide
12. customwas formed
13. filtrationThe suspension was filtered
14. washthe solid washed with 10 ml 1 N NaOH
15. additionTo the filtrate was added 2 mL of 3N HCl
16. stirringwith stirring
17. customto precipitate
18. filtrationThe tetrazole was filtered
19. washwashed with 5 mL of 3N HCl
20. customdried in vacuo
21. customto afford white powder