1,5-C,C-Cycloalkylation of tert-butyl acetoacetate (1) with cis-1,4-dichloro-2-butene (2) followed by the haloform reaction of the product in NaOH solution and subsequent Curtius degradation in tert-butyl alcohol furnished tert-butyl 1-tert-butoxycarbonylaminocyclopent-3-enecarboxylate (5) in 32% overall yield.
1,5-C,C-环烷基化
叔丁基乙酰乙酸酯(1)与
顺式-1,4-二氯-2-丁烯(2)反应,然后在NaOH溶液中进行卤代反应,并在
叔丁醇中进行后续的Curtius降解,最终得到叔丁基1-叔丁氧羰基
氨基
环戊-3-烯羧酸酯(5),总产率为32%。