Tetrahydrofuran → 1-Methyl-5-(3-propionylpropyl)thio-1,2,3,4-tetrazole

Temperatur

-78 °C

2-Ethyl-1,3,-dithian (1,5 g) is dissolved in dried tetrahydrofuran (20 ml) and cooled to -78° C. To the mixture is added dropwise 1.6 N solution of n-butyllithium in n-hexane (6.5 ml) with stirring in argon gas flow. The mixture is stirred at -78° C. for 30 minutes. To the mixture is added dropwise a solution of 1-methyl-5-(3-chloropropyl)thio-1,2,3,4-tetrazole (1.9 g) in dried tetrahydrofuran (5 ml). After stirring at -78° C. for 1 hour, the mixture is stirred 4 hours while it is heated slowly to 0° C. The reaction mixture is poured into ice-water and extracted with ether. The ether solution is washed with water and saturated aqueous sodium chloride and dried over magnesium sulfate. After ether is distilled off, the residue is dissolved in acetonitrile (20 ml). Silver nitrate (7 g) and N-chlorosuccinimide (4.9 g) are dissolved in a mixture of water (40 ml) and acetonitrile (100 ml). To the mixture is added dropwise the dithian solution as above-mentioned with stirring at 0° C. in nitrogen gas flow. After stirring at 0° C. for 30 minutes, the mixture is heated to room temperature and further stirred for 30 minutes. The reaction mixture is diluted with water and extracted with chloroform. The chloroform solution is washed with water and saturated aqueous sodium chloride and dried over magnesium sulfate. After chloroform is distilled off, the residue is purified by column chromatography (Kieselgel 60) and eluted with benzene-ether (10:1) to give 1-methyl-5-(3-propionylpropyl)thio-1,2,3,4-tetrazole (0.3 g) as colorless liquid, nD25 =1.5042

1. stirringThe mixture is stirred at -78° C. for 30 minutes
2. stirringAfter stirring at -78° C. for 1 hour
3. stirringthe mixture is stirred 4 hours while it
4. temperatureis heated slowly to 0° C
5. extractionextracted with ether
6. washThe ether solution is washed with water and saturated aqueous sodium chloride
7. dry with materialdried over magnesium sulfate
8. distillationAfter ether is distilled off
9. dissolutionthe residue is dissolved in acetonitrile (20 ml)
10. dissolutionSilver nitrate (7 g) and N-chlorosuccinimide (4.9 g) are dissolved in a mixture of water (40 ml) and acetonitrile (100 ml)
11. additionTo the mixture is added dropwise the dithian solution as above-mentioned
12. stirringwith stirring at 0° C. in nitrogen gas flow
13. stirringAfter stirring at 0° C. for 30 minutes
14. temperaturethe mixture is heated to room temperature
15. stirringfurther stirred for 30 minutes
16. additionThe reaction mixture is diluted with water
17. extractionextracted with chloroform
18. washThe chloroform solution is washed with water and saturated aqueous sodium chloride
19. dry with materialdried over magnesium sulfate
20. distillationAfter chloroform is distilled off
21. customthe residue is purified by column chromatography (Kieselgel 60)
22. washeluted with benzene-ether (10:1)

ORD-Eintrag

ord-cc724d50c20c4b51bf760ba75b83a509

Quelldatensatz

uspto-grants-1983_02

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US04372953