Palladium-Catalyzed Oxidative C≡C Triple Bond Cleavage of 2-Alkynyl Carbonyl Compounds Toward 1,2-Dicarbonyl Compounds?

Article abstract of DOI:10.1002/cjoc.202000040

A new, general palladium-catalyzed oxidative strategy for the cleavage of the C≡C triple bond is presented. By employing PdCl₂, CuBr₂, TEMPO and air as the catalytic system and H₂O as the carbonyl oxygen atom source, a wide range of 2-alkynyl carbonyl compounds, including 1,3-disubstituted prop-2-yn-1-ones, propiolamides and propiolates, lost an alkynyl carbon to access various 1,2-dicarbonyl compounds, e.g., 1,2-diones, 2-keto amides and 2-keto esters, through Wacker oxidation, intramolecular cyclization and C—C bond cleavage cascades.