Synthesis of 7-Membered Ring Carbocycles via a Palladium-Catalyzed Intramolecular Allylic Alkylation-Isomerization-Cope Rearrangement Cascade
Synthesis of 7-Membered Ring Carbocycles via a Palladium-Catalyzed Intramolecular Allylic Alkylation-Isomerization-Cope Rearrangement Cascade
复制标题
通过钯催化分子内烯丙基烷基化-异构化-Cope 重排级联合成七元环碳环
DOI：
10.1002/ejoc.201800230
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
and Tetsuhiro Nemoto
中科院分区：
文献类型：
--
作者：
Kazuki Tsuruda;Takahisa Tokumoto;Naoya Inoue;Masaya Nakajima;and Tetsuhiro Nemoto
我们开发了一种通过钯催化的分子内烯丙基烷基化-异构化- cope重排级联反应合成七元环碳环的新方法。使用容易获得的内酯衍生物作为底物，在THF中存在5mol - %的Pd(dba)2和6mol - %的1,3 -二苯基膦丙烷（dppp）的情况下进行目标级联反应，以59 - 88%的收率提供一系列七元环碳环（11个例子）。DFT计算表明，除了包括二乙烯基环丙烷Cope重排的反应级联外，还有另一种可能的途径是基于钯催化的分子内烯丙基取代，通过逆环丙烷化介导的氧化加成来构建七元环。
We developed a novel method for synthesizing seven‐membered ring carbocycles via a palladium‐catalyzed intramolecular allylic alkylation–isomerization–Cope rearrangement cascade. Using easily available lactone derivatives as substrates, the target cascade reaction proceeded in the presence of 5 mol‐% of Pd(dba)2and 6 mol‐% of 1,3‐diphenylphosphinopropane (dppp) in THF, affording a series of seven‐membered ring carbocycles in 59–88 % yield (11 examples). DFT calculations suggested that, in addition to the reaction cascade including thecis‐divinylcyclopropane Cope rearrangement, there is another possible pathway based on the palladium‐catalyzed intramolecular allylic substitution to construct the seven‐membered ring through a retro‐cyclopropanation‐mediated oxidative addition.