反应详情

To a solution of Boc-D-Orn-OH (0.50 g, 2.2 mmol) in aqueous NaOH (1M, 5 mL) at 0° C. was added benzyl chloroformate (0.37 mL, 2.6 mmol, 1.2 equiv) followed by aqueous NaOH (1M, 5 mL). After stirring for 2 hours at room temperature, the reaction mixture was poured to separatory funnel and extracted with ether. The aqueous layer was acidified to pH 3 with aqueous 10% citric acid and extracted with ethyl acetate. The combined organic layer was washed with brine, dried with Na2SO4, filtered and concentrated in vacuo to afford compound 3.2.1a (0.57 g, 72%) which was used for the next step without further purification. MS m/z (M+Na) 389.2. 1H NMR (400 MHz, DMSO-d6) 12.37 (br-s, 1H), 7.35-7.25 (m, 5H), 7.20 (t, J=5.31 Hz, 1H), 7.01 (d, J=8.02 Hz, 1H), 4.97 (s, 2H), 3.83-3.77 (m, 1H), 2.94 (dd, 2H), 1.67-1.56 (m, 1H), 1.53-1.37 (m, 3H), 1.34 (s, 9H).

1. additionthe reaction mixture was poured to separatory funnel
2. extractionextracted with ether
3. extractionextracted with ethyl acetate
4. washThe combined organic layer was washed with brine
5. dry with materialdried with Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customto afford compound 3.2.1a (0.57 g, 72%) which
9. customwas used for the next step without further purification