Hydrazoic acid → 5-(3-chloropropyl)-1-cyclohexyltetrazole

Into 200 ml of dried benzene, 30.6 g of N-γ-chlorobutyrylcyclohexylamine was added. While the inside temperature is kept below 20° C. by ice-cooling the outside of the reaction vessel, 30 g of PCl5 was added under stirring condition. After completion of the addition, the stirring is continued for 2 hours at a room temperature, then the reaction mixture is concentrated to a half volume thereof by using an evaporator with a bath temperature of below 50° C. To the concentrated reaction mixture was added dropwise 140 ml of benzene containing 10% of HN3 under stirring condition for 90 minutes while keeping the inside temperature below 15° C. After the addition operation, the reaction mixture is allowed to stand overnight at room temperature. Then the reaction mixture is refluxed for 3 hours with stirring and is concentrated. The thus obtained concentrate is extracted with 200 ml of chloroform. The chloroform layer is washed with 5% NaHCO3 aqueous solution and with water and dried with Na2SO4. After removal of the drying agent, the mother liquor is concentrated and the residue thus obtained is recrystallized from water-containing isopropanol to obtain 28 g of 1-cyclohexyl-5-γ-chloropropyltetrazole in the form of colorless needle like crystals. Melting point: 82°-85° C.

1. customis kept below 20° C. by ice-
2. additionwas added
3. additionAfter completion of the addition
4. concentrationthe reaction mixture is concentrated to a half volume
5. customan evaporator with a bath temperature of below 50° C
6. customTo the concentrated reaction mixture
7. stirringunder stirring condition for 90 minutes
8. customthe inside temperature below 15° C
9. waitto stand overnight at room temperature
10. temperatureThen the reaction mixture is refluxed for 3 hours
11. stirringwith stirring
12. concentrationis concentrated
13. customThe thus obtained
14. concentrationconcentrate
15. extractionis extracted with 200 ml of chloroform
16. washThe chloroform layer is washed with 5% NaHCO3 aqueous solution and with water
17. dry with materialdried with Na2SO4
18. customAfter removal of the drying agent
19. concentrationthe mother liquor is concentrated
20. customthe residue thus obtained
21. customis recrystallized from water-
22. additioncontaining isopropanol

ORD record

ord-59dc48467eda4cfc855f4554d627833b

Source dataset

uspto-grants-1981_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04277479