Department of Organic Chemistry, Institute of Chemistry, Saint Petersburg State University, Universitetskaya nab., 7/9, Saint Petersburg 199034, Russia.
Department of Crystallography, Institute of Earth Sciences, Saint Petersburg State University, Universitetskaya nab., 7/9, Saint Petersburg 199034, Russia.
Molecules. 2018 Nov 25;23(12):3079. doi: 10.3390/molecules23123079.
The TfOH-mediated reactions of 2,4-diaryl-1,1,1-trifluorobut-3-yn-2-oles (CF₃-substituted diaryl propargyl alcohols) with arenes in CH₂Cl₂ afford 1,3-diaryl-1-CF₃-indenes in yields up to 84%. This new process for synthesis of such CF₃-indenes is complete at room temperature within one hour. The synthetic potential, scope, and limitations of this reaction were illustrated by more than 70 examples. The proposed reaction mechanism invokes the formation of highly reactive CF₃-propargyl cation intermediates that can be trapped at the two mesomeric positions by the intermolecular nucleophilic attack of an arene partner with a subsequent intramolecular ring closure.
三氟甲磺酸介导的 2,4-二芳基-1,1,1-三氟-3-丁炔-2-醇（CF₃取代的二芳基丙炔醇）与芳环在 CH₂Cl₂中的反应，以高达 84%的收率得到 1,3-二芳基-1-CF₃-茚满。这种合成此类 CF₃-茚满的新方法在室温下 1 小时内即可完成。通过 70 多个实例说明了该反应的合成潜力、范围和局限性。提出的反应机制涉及到高反应性的 CF₃-丙炔阳离子中间体的形成，这些中间体可以通过芳环伙伴的分子间亲核进攻在两个中位位置被捕获，随后进行分子内环化。
