反应详情

温度

50 °C

To a solution of [(1RS,2SR)-2-aminocyclopentyl-carbamic acid 1,1-dimethylethyl ester (CAS 365996-19-6) (500 mg, 2.497 mmol) in 10 ml methanol was added acetic acid (0.714 ml, 12.49 mmol) and cyclopentanone (0.665 ml, 7.491 mmol). The mixture was heated in a 50° C. oil bath for 1.5 hour. The solution was cooled to room temperature and sodium cyanoborohydride (370 mg, 5.0 mmol) was added portionwise. The mixture was heated in a 50° C. oil bath for 2.5 hours. The solution was cooled in an ice bath and quenched by dropwise addition of 6 ml 2N NaOH. The methanol was removed in vacuo. The aqueous layer was diluted with water and extracted 3 times with ethyl acetate. The combined extracts were dried over Na2SO4, filtered and concentrated in vacuo. The crude oil was purified on silica gel (eluent: heptane/ethyl acetate 0 to 100%) to provide 0.39 g (58%) of the title compound as a light brown solid. MS (m/e): 269.3 (M+H).

1. temperatureThe solution was cooled to room temperature
2. temperatureThe mixture was heated in a 50° C. oil bath for 2.5 hours
3. temperatureThe solution was cooled in an ice bath
4. customquenched by dropwise addition of 6 ml 2N NaOH
5. customThe methanol was removed in vacuo
6. additionThe aqueous layer was diluted with water
7. extractionextracted 3 times with ethyl acetate
8. dry with materialThe combined extracts were dried over Na2SO4
9. filtrationfiltered
10. concentrationconcentrated in vacuo
11. customThe crude oil was purified on silica gel (eluent: heptane/ethyl acetate 0 to 100%)