Polysubstituted isocoumarins such as thunberginol A were synthesized by the reaction of substituted 2-(trimethylsilyl)phenyl triflate with trifluoromethylated β-diketones in the presence of CsF. The reaction proceeded via carbon–carbon bond insertion of aryne followed by intramolecular cyclization and CF3 anion extrusion. The –C(···O)CF3 unit has high potential for not only the nucleophilic moiety but also a useful leaving group of CF3.
多取代的异
香豆素如Thunberginol A是通过在CsF存在下,将取代的2-(三甲基
硅基)苯
三氟甲磺酸酯与三
氟甲基化的
β-二酮反应合成的。该反应是通过芳基炔的碳-碳键插入,再进行分子内环化和
CF3阴离子的挤出进行的。-C(···O) 单元不仅具有成为亲核基团的高潜力,还具有作为 有用离去基团的优点。