反应详情

1,4-butanediamine dihydrochloride (5.96 g, 37 mmol) was dissolved in water (15 mL), and DMF (50 mL) was added. With rapid stirring, CBZ-Cl (1.0 mL, 7.0 mmol) was added dropwise over 2 minutes. The cloudy solution had pH~2.8. The pH was adjusted to 9.0 with 5N NaOH, (clear solution) and stirred for 2 hr. The reaction mixture was acidified to pH=1.25, extracted with ether (2×), made basic (pH>10) with 5N NaOH, and extracted with dichloromethane (2×). The dichloromethane fractions were combined and washed with water (2×), dried and evaporated in vacuo to provide the crude mono-CBZ amine (0.72 g, 3.24 mmol, 46%) which was used as is in the next step.

1. extractionextracted with ether (2×)
2. extractionextracted with dichloromethane (2×)
3. washwashed with water (2×)
4. customdried
5. customevaporated in vacuo