An N-heterocyclic carbene-catalyzed synthesis of dibenzofulvenes and fluorenyl alcohols was developed. In the presence of 10 mol% NHC (1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) and 4 Å molecular sieves, 9-(trimethylsilyl)fluorene undergoes an olefination reaction with aldehydes to produce dibenzofulvenes in 43–99% yields. However, on reducing the NHC loading to 1 mol% and with the addition of water, 9-(trimethylsilyl)fluorene selectively undergoes nucleophilic addition with aldehydes to afford fluorenyl alcohols in 40–95% yields.

中文翻译：

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N-杂环卡宾催化的9-（三甲基甲硅烷基）芴与醛的可转换反应：二苯并富勒烯和芴醇的化学选择性合成

开发了N-杂环卡宾催化的二苯并富勒烯和芴醇的合成。在10摩尔％NHC（1,3-双（2,6-二异丙基苯基）咪唑-2-亚基）和4Å分子筛的存在下，9-（三甲基甲硅烷基）芴与醛进行烯化反应以在43中生成二苯并富烯–99％的收益率。但是，在将NHC含量降至1 mol％并添加水后，9-（三甲基甲硅烷基）芴选择性地与醛进行了亲核加成反应，从而以40-95％的产率获得了芴醇。