Aryne Generation from o-Triazenylarylboronic Acids Induced by 1,2-Diols and 4-Nitrophenol
Motoki Ito1, Hiroki Yomo1, Kazuhiro Higuchi1
1Meiji Pharmaceutical University, 2-522-1 Noshio, Kiyose, Tokyo 204-8588, Japan.
Abstract:
Arynes are important synthetic intermediates that are usually generated under alkaline conditions. We developed a method for generating arynes using two hydroxy compounds as activators. o-Triazenylarylboronic acids generate (hetero)arynes when activated by a combination of ethylene glycol, pinacol, and p-nitrophenol; these arynes then react with a range of arynophiles under slightly acidic conditions that complement the conventional basic conditions with unique chemoselectivities observed even in the presence of excess hydroxy compounds.
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