In this communication, we report a substrate‐controlled product diversity in the 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD)‐catalyzed cascade cyclization of 2‐alkynyl‐3,3‐difluoro‐3H‐indoles with N,N‐ or N,S‐bis‐nucleophiles. The products represent two important heterocyclic compounds, C2‐spiro indoline, and pyrimido[1,2‐a]benzimidazole, featuring a versatile gem‐difluoromethylene group on the framework. In these cascade processes, two new C−N bonds, or one C−S and one C−N bond, are consecutively formed in a single step. The present protocol is characterized with high regioselectivity, high yield, broad substrate scope, good functional group tolerance, facile scalability and mild reaction conditions.

中文翻译：

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从2-炔基-3,3-二氟-3H-吲哚类化合物催化合成宝石二氟化C2-螺二氢吲哚和嘧啶并[1,2-a]苯并咪唑

在本交流中，我们报告了在1,5,7-三氮杂双环[4.4.0] dec-5-烯（TBD）催化的2-炔基-3,3-二氟-3级联环化反应中，受基质控制的产品多样性具有N，N-或N，S-双亲核试剂的H吲哚。产品代表两个重要的杂环化合物，C2-螺吲哚啉和嘧啶并[1,2- a ]苯并咪唑，在骨架上具有通用的宝石-二氟亚甲基基团。在这些级联过程中，两个新的CN键或一个CS和一个CN键在一个步骤中连续形成。本协议的特点是区域选择性高，收率高，底物范围广，官能团耐受性好，可扩展性和温和的反应条件。