A four-step domino-multicomponent reaction (domino-MCR) is described for the synthesis of functionalized E-alkylidenecyclobutanes from 4-hydroxy-2-methylcyclopent-2-enone derivatives and three other simple reagents. The domino-MCR is accomplished in a single protocol, comprising a tandem photochemical [2 + 2]-cycloaddition/Norrish-I/γ-H transfer reaction followed by an acetal protection and an allylic substitution reaction. In parallel, a consecutive process has been established with distinct photochemical and nonradiative sequences. An intramolecular version of these reactions provides access to complex fused-bicyclic alkylidenecyclobutanes.

中文翻译：

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光引发四步多米诺多组分合成官能化烷基环丁烷


描述了一种四步多米诺-多组分反应 （domino-MCR），用于从 4-羟基-2-甲基环戊-2-烯酮衍生物和其他三种简单试剂合成官能化的 E-烷基环丁烷。Domino-MCR 在单个方案中完成，包括串联光化学 [2 + 2] -环加成反应/Norrish-I/γ-H 转移反应，然后是缩醛保护和烯丙基取代反应。同时，已经建立了一个具有不同光化学和非辐射序列的连续过程。这些反应的分子内版本提供了对复合稠合双环烷基环丁烷的访问。