反应 #806291

反应方程式

4-Methylleucine

NaOH

ninhydrine EtOH

Perchloric acid

Na2CO3

→

tert-Butyl 4-methylleucinate

收率 96.0%

溶剂

DCM

MeOH

t-butyl acetate

diethyl ether

toluene

EtOAc

反应条件

后处理

1. 1
   workup.ADDITIONThe solution was poured into a flask
2. 2
   其他The phases were separated
3. 3
   洗涤the aq-phase was washed with 2×30 ml EtOAc
4. 4
   洗涤The combined organic phases were washed with brine
5. 5
   干燥dried with Na2SO4
6. 6
   其他evaporated
7. 7
   其他A oil was obtained which

实验过程

4-Methylleucine (500 mg, 3.44 mmol) was suspended in 10 ml t-butyl acetate. Perchloric acid (0.2 ml, 3.49 mmol) was added and the flask was stopped with a septum and stirred over night. Analysis was performed using TLC DCM:MeOH, 9:1; staining with a ninhydrine/EtOH solution). The solution was poured into a flask containing 30 ml EtOAc and 30 ml 5% Na2CO3. The aq-layer turned acidic and 2M NaOH was added until pH was approximately 7. The phases were separated and the aq-phase was washed with 2×30 ml EtOAc. The combined organic phases were washed with brine, dried with Na2SO4 and evaporated. A oil was obtained which was co-evaporated with toluene and then with diethyl ether before being placed under vacuum for two days. Mass 665 mg (96% yield). NMR (CDCl3): 1.0 (s, 9H), 1.5 (s, 9H), 1.65–1.95 (m, 2H), 3.82 (t, 1H).

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