A [3 + 1 + 1] cascade annulation reaction for the divergent construction of trisubstituted indolizines using sulfoxonium ylides, BrCF₂CO₂Me and pyridinium salts as readily available substrates has been developed. By changing the reaction conditions, this metal-free process realized selective cleavage of one or two C–F bonds of difluorocarbene and let it act as a C or CF source. Further transformation of the product presented the practicality of this reaction.

中文翻译：

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碱基控制选择性裂解二氟卡宾的 C-F 键以实现中氮茚的不同组装


开发了一种 [3 + 1 + 1] 级联环化反应，使用亚锍叶立德、BrCF ₂ CO ₂ Me 和吡啶鎓盐作为容易获得的底物来不同地构建三取代中氮茚。通过改变反应条件，这种无金属工艺实现了二氟卡宾的一个或两个C-F键的选择性断裂，并使其充当C或CF源。产物的进一步转化表明了该反应的实用性。