反应 #640536

反应方程式

N-4-methoxybenzyloxycarbonyl α-methyl β-alanine methyl ester

lithium hydroxide

→

N-4-Methoxybenzyloxycarbonyl α-methyl β-alanine

收率 97.3%

溶剂

methanol

反应条件

后处理

1. 1
   浓缩The solution was concentrated in vacuo
2. 2
   workup.ADDITIONthe residue taken up in a mixture of water and ether
3. 3
   其他the phases separated
4. 4
   萃取extracted three times with ether
5. 5
   洗涤The combined ethereal phase was washed with saturated aqueous sodium chloride solution
6. 6
   干燥dried over anhydrous magnesium sulfate
7. 7
   过滤filtered
8. 8
   浓缩concentrated in vacuo

实验过程

A solution of N-4-methoxybenzyloxycarbonyl α-methyl β-alanine methyl ester (2.81 g, 10.0 mmol) in 30 mL of 25% aqueous methanol was treated with lithium hydroxide (1.3 equivalents) at room temperature for a period of 2 h. The solution was concentrated in vacuo and the residue taken up in a mixture of water and ether and the phases separated and the organic phase discarded. The aqueous phase was acidified with aqueous potassium hydrogen sulfate to pH=1.5 and then extracted three times with ether. The combined ethereal phase was washed with saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated in vacuo to give 2.60 g, 97% of N-4-Methoxybenzyloxycarbonyl α-methyl β-alanine (N-Moz-AMBA) which was purified by recrystallization from a mixture of ethyl acetate and hexane to give 2.44 g, 91% of pure product, mp 96-97° C., MH+=268. 1H NMR (D6-acetone/300 MHz) 1.16 (3H, d, J=7.2Hz), 2.70 (1H, m), 3.31 (2H, m), 3.31 (3H, s), 4.99 (2H, s), 6.92 (2H, 4, J=8.7 Hz), 7.13 (2H, d, J=8.7 Hz).

来源