反应详情

温度

0 °C

A solution of ethyl 4-piperidinecarboxylate (14.71 g) and triethylamine (12.04 g) in chloroform (200 mL) was cooled to 0° C. and treated dropwise with benzyl chloroformate (17.91 g). The resulting mixture was stirred at 0° C. for 1 hour, then was warmed to room temperature and was stirred for 12 hours. The mixture was then washed (1N hydrochloric acid, brine), dried, filtered and evaporated to yield a pale yellow oil (26.4 g). The oil was purified by chromatography, with dichloromethane:methanol (95.5) as the eluent, to afford the urethane as a colorless syrup (22.15 g); NMR: 7.35 (m, 5), 5.07 (s, 2), 4.06 (q,2, J=7.0), 3.91 (broad d, 2, J=13.3), 2.95 (broad, 2), 2.53 (m, 1), 1.82 (broad d, 2, J=13.3), 1.41 (m, 2), 1.18 (t, 3, J=7.0).

1. temperaturewas warmed to room temperature
2. stirringwas stirred for 12 hours
3. washThe mixture was then washed (1N hydrochloric acid, brine)
4. customdried
5. filtrationfiltered
6. customevaporated