反应详情

Under nitrogen, 60.0 g (0.30 mol) of N-BOC-γ-aminobutyric acid (BACHEM) is dissolved in 1200 mL of methylene chloride and treated with 30.5 g (0.15 mol) of dicyclohexylcarbodiimide (DCC). The reaction is allowed to stir for 2 hours and filtered under nitrogen. The anhydride solution is then added to a solution of 1.58 g (98.5 mmol) of anhydrous hydrazine in 100 mL of methylene chloride at 0° C. The reaction is allowed to warm to ambient temperature and stirred overnight. Concentration in vacuo gives the crude hydrazide which is purified either by recrystallization or by silica gel chromatography (Waters Prep-500A). A 21.7 g (100 mmol) sample of hydrazide is dissolved in 100 mL of methanol and treated with 12.9 g (100 mmol) of ethyl iminovalerate under nitrogen. The reaction is stirred at reflux overnight and concentrated in invacuo. Purification by silica gel chromatography (Waters Prep-500A) gives 5-butyl-3-(3-tertbutoxycarbonylaminopropyl-1H-1,2,4-triazole.

1. filtrationfiltered under nitrogen
2. stirringstirred overnight
3. concentrationConcentration in vacuo
4. customgives the crude hydrazide which
5. customis purified either by recrystallization or by silica gel chromatography (Waters Prep-500A)
6. dissolutionA 21.7 g (100 mmol) sample of hydrazide is dissolved in 100 mL of methanol
7. stirringThe reaction is stirred
8. temperatureat reflux overnight
9. concentrationconcentrated in invacuo
10. customPurification by silica gel chromatography (Waters Prep-500A)