作者:A. Fadel、J. Salaün、J.M. Conia
DOI:10.1016/s0040-4020(01)88564-1
日期:1983.1
Cyclobutene, prepared by base-induced elimination from tosyloxycyclobutane 19 undergoes cycloaddition with ethyl propiolate in the presence of AlCl3 to provide ethyl bicyclo[2.2.0]hex-2-ene-2-carboxylate 20. This cycloadduct at room temperature and in the presence of AlCl3 undergoes forbidden ring opening into ethyl cyclohexa-1,3-diene-2-carboxylate 21. The cycloaddition of cyclobutene with dichloroketene
通过从甲苯磺酰氧基环丁烷19的碱诱导的消除反应制得的环丁烯在AlCl 3存在下与丙酸乙酯进行环加成反应,以提供双环[2.2.0] hex-2-ene-2-羧酸乙酯20。该环加合物在室温下和在存在AlCl 3的情况下,被禁止开环成环己-1,3-二烯-2-羧酸乙酯21。环丁烯与二氯乙烯烯的环加成反应可得到3,3-二氯双环[2.2.0]己-2-酮24,还原卤素去除后,内环3-氯双环[2.2.0]己-2-酮28(这个紧张的系统)。但是,进一步脱氯28 导致重排和片段化反应。