Divergent synthesis of cyclopentenyl- & 1,5-divinyl-ketones via gold-catalyzed oxidative coupling of 1,3-enynes with various olefins

Two divergent synthetic routes were developed to synthesize cyclopentenyl- & 1,5-divinyl-ketones through gold catalyzed reaction of 1,3-enynes with different types of olefins with the addition of pyridine N-oxide. A formal [3 + 2] cycloaddition occurred in the reaction of aryl olefins by using 1,3-enynes as the C3 reactants, while the C1 reactivity thereof was exhibited in the reaction with alkyl olefins to provide 1,5-divinyl ketone products.