反应详情

温度

60 °C

In a 50 ml round-bottom flask the amine 5 (1.65 g 4.7 mmol) was dissolved in acetonitrile (15 ml) and K2CO3 (5.16 g, 37 mmol) was added. t-Butyl bromoacetate (4.55 g, 23.4 mmol) was slowly dropped into the stirred heterogeneous mixture, while maintaining the temperature <10° C. (ice bath). After the addition the mixture was heated at 60° C. with stirring until TLC showed complete conversion. The precipitate was filtered and washed with dichloromethane; the filtrate and the washings were combined and evaporated in vacuo to give the crude product. The semisolid residue was purified by silica gel chromatography (petroleum ether/ethyl acetate 9.3/0.7), obtaining pure 6 as pale yellow oil (1.35 g, 36%). ESI-MS: 832 (MNa+), 810 (MH+); (Calc. for C46H87N3O8: 809 u.m.a.).

1. temperaturewhile maintaining the temperature <10° C. (ice bath)
2. additionAfter the addition the mixture
3. filtrationThe precipitate was filtered
4. washwashed with dichloromethane
5. customevaporated in vacuo
6. customto give the crude product
7. customThe semisolid residue was purified by silica gel chromatography (petroleum ether/ethyl acetate 9.3/0.7)