反应详情

A suspension of L-glutamic acid (23.5 g; 160 mmol) in H2O (100 mL) was stirred, maintaining the pH at 8.5 with 10 M NaOH until complete dissolution. Benzyl chloroformate (35 g; 205 mmol) was added over 15 min to the clear solution. The mixture was stirred, maintaining the pH at 9 by adding 10 M NaOH until the reaction was complete. The cloudy mixture was washed with Et2O (3×150 mL) and then the pH of the resulting solution was adjusted to 2.1 with 1 M HCl. The cloudy aqueous mixture was extracted with Et2O (2×200 mL), the organic layers were collected and evaporated to yield the desired product (39.13 g; 139 mmol). Yield 87%.

1. dissolutionuntil complete dissolution
2. stirringThe mixture was stirred
3. temperaturemaintaining the pH at 9
4. washThe cloudy mixture was washed with Et2O (3×150 mL)
5. extractionThe cloudy aqueous mixture was extracted with Et2O (2×200 mL)
6. customthe organic layers were collected
7. customevaporated