Highly selective formal [3 + 2]-cycloaddition of vinyldiazoacetates with quinone ketals and quinoneimine ketals has been accomplished at room temperature with catalytic amounts of the Brønsted acid triflimide, leading to highly functionalized diazoacetates in good yields. The vinyldiazonium ion generated by electrophilic addition to the vinylogous position of the reactant vinyldiazo compound is the key intermediate in this selective transformation. Both oximidovinyldiazoacetates and those with other vinyl substituents undergo cycloaddition reactions with quinone ketals whose products, after extended reaction times, undergo substrate-dependent 1,2-migration; catalysis by Rh₂(OAc)₄, HNTf₂, and Sc(OTf)₃ effects these 1,2-migrations to the same products. However, the products from HNTf₂-catalyzed reactions between quinoneimine and oximidovinyldiazoacetates undergo Rh₂(OAc)₄-catalyzed 1,3-C–H insertion. 1,3-Difunctionalization products are obtained for electrophilic reactions of Eschenmoser’s salt with selected vinyldiazoacetates, but with α-dibenzylaminomethyl ether, 1,6-hydride transfer reactions are observed with oximidovinyldiazoacetates.

中文翻译：

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重氮乙酸乙烯酯催化[3+2]环化构建重氮化合物及其合成应用

重氮乙酸乙烯酯与醌缩酮和醌亚胺缩酮的高选择性形式[3 + 2]-环加成反应已在室温下用催化量的布朗斯台德酸三氟甲酰亚胺完成，从而以良好的收率获得高度官能化的重氮乙酸酯。通过亲电加成反应物乙烯基重氮化合物的插烯位置产生的乙烯基重氮离子是该选择性转化中的关键中间体。肟基乙烯基重氮乙酸酯和具有其他乙烯基取代基的那些都会与醌缩酮发生环加成反应，其产物在延长反应时间后会发生底物依赖性1,2-迁移； Rh ₂ (OAc) ₄、HNTf ₂和Sc(OTf) ₃的催化作用会导致这些1,2-迁移到相同的产物。然而，HNTf ₂催化的醌亚胺和肟基乙烯基重氮乙酸酯之间的反应产物会经历Rh ₂ (OAc) ₄催化的1,3-C-H 插入。 Eschenmoser 盐与选定的重氮乙酸乙烯基酯发生亲电反应，得到 1,3-双官能化产物，但与 α-二苄基氨基甲基醚发生亲电反应，并与肟基乙烯基重氮乙酸酯发生 1,6-氢化物转移反应。