反应 #1810811

反应方程式

sodium carbonate

Perchloric acid

(S)-pyroglutamic acid

tert-butyl acetate

→

ester

收率 56.4%

(S)-tert-Butyl pyroglutamate

收率 56.4%

溶剂

ether

carbon tetrachloride

反应条件

后处理

1. 1
   洗涤the organic phase washed with saturated sodium hydrogen carbonate solution and brine
2. 2
   萃取The aqueous phase was extracted with ethyl acetate
3. 3
   干燥dried (MgSO4)
4. 4
   过滤filtered
5. 5
   其他the solvent removed
6. 6
   其他to yield an oil to which
7. 7
   其他the solvent evaporated in vacuo
8. 8
   其他to remove traces of acetic acid

实验过程

Perchloric acid (70% aqueous, 0.521 cm3, 6.05 mmol) was added dropwise to a stirred suspension of (S)-pyroglutamic acid 9 (1 g, 7.75 mmol) in tert-butyl acetate (12 cm3, 85.5 mmol). The mixture was stirred for 24 h then sodium carbonate (0.80 g, 7.60 mmol) was added cautiously, ether was added and the organic phase washed with saturated sodium hydrogen carbonate solution and brine. The aqueous phase was extracted with ethyl acetate, dried (MgSO4), filtered and the solvent removed to yield an oil to which was added carbon tetrachloride and the solvent evaporated in vacuo to remove traces of acetic acid to give ester 10 (0.81 g, 56%) as a white solid: δH (300 MHz; CDCl3; Me4Si) 1.48 [9H, s, C(CH3)], 2.33-2.45 (4H, m, 3-H2, 4-H2), 4.12-4.16 (1H, m, 5-H) and 6.16 (1H, br s, N—H); δC (75 MHz; CDCl3) 24.7 (CH2, 4-C), 27.8 [CH3, C(CH3)], 29.2 (CH2, 3-C), 55.9 (CH, 5-C), 82.3 [quat., C(CH3)], 170.9 (quat., 5-CO) and 177.7 (quat., 2-C).

来源