One Pot Synthesis of Substituted Tropones from 7,7-Dihalo-2,3-(or 3,4-)epoxybicyclo[4.1.0]heptane Derivatives
作者:Masahiko Kato、Shigeyuki Yamamoto、Shigeki Nomura、Toshio Miwa
DOI:10.1246/bcsj.63.64
日期:1990.1
In order to obtain a scope and limitations of the reaction for newly developed tropone synthesis, some substituted 2,3- and 3,4-epoxy-7,7-dihalobicyclo[4.1.0]heptanes have been prepared and treated with several acids. We found that (1) the epoxy-carbons of starting materials should have, at least, one substituent which may stabilize the carbenium ion formed by cleavage of the epoxide with acid, (2)
为了获得新开发的托酮合成反应的范围和限制,一些取代的 2,3- 和 3,4-环氧-7,7-二卤代双环 [4.1.0] 庚烷已被制备并用几种酸处理。我们发现 (1) 起始材料的环氧碳应该至少有一个取代基,该取代基可以稳定环氧化物用酸裂解形成的碳正离子,(2) 作为起始材料中的卤素,溴优于(3) 推荐在回流温度下在氯仿中对底物使用 20 摩尔当量的 TFA,或在 100°C 下在甲苯中对底物使用各 5 摩尔当量的 TCA 和水。