One-pot transformation of Ph₂P(O)-protected ethynes: Deprotection followed by transition metal-catalyzed coupling

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.