An efficient approach for the synthesis of trifluoroacetimidoyl-substituted dihydrobenzofurans through a metal-free [4+1] annulation reaction of in-situ generated o-QMs with TFISYs has been reported. The protocol enables the formation of various biologically important trifluoromethyl-containing dihydrobenzofurans in up to 95 % yield with good to excellent diastereoselectivities under mild conditions.

中文翻译：

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通过原位生成的邻醌甲基化物和 CF3−亚氨基磺叶立德的形式 [4+1] 环化合成含三氟甲基的 2,3-二氢苯并呋喃

据报道，通过原位生成的o -QM与TFISY的无金属[4+1]成环反应合成三氟乙酰亚氨基取代的二氢苯并呋喃的有效方法。该方案能够在温和条件下以高达 95% 的产率形成各种具有重要生物学意义的三氟甲基的二氢苯并呋喃，并具有良好至优异的非对映选择性。