One-pot transformation of Ph2P(O)-protected ethynes: deprotection followed by transition metal-catalyzed coupling
Lifen Peng1, Feng Xu, Yoshinori Suzuma
1Department of Applied Chemistry, Okayama University of Science , Kita-ku, Okayama 700-0005, Japan.
Abstract:
Ph2P(O)-protected ethynes were successfully transformed to arylethynes in one-pot manner through t-BuOK-catalyzed deprotection followed by Sonogashira coupling with aryl halide. The arylethynes were obtained similarly by Ph2P(O)-deprotection, stannylation of the resulting terminal ethynes, and Migita-Kosugi-Stille coupling. Deprotection followed by intramolecular Eglinton coupling could be carried out in one-pot to provide cyclic butadiynes.
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