Pd/C-Catalyzed coupling and cyclization of β-bromo-α,β-unsaturated carboxylic acids with terminal alkynes leading to alkylidenefuranones

Palladium-catalyzed coupling of β-bromo-α,β-unsaturated carboxylic acids with terminal alkynes and subsequent regioselective 5-exo-dig cyclization produces (Z)-alkylidenefuranones in good yields.

-Bromo--unsaturated carboxylic acids are coupled and cyclized with terminal alkynes in the presence of a palladium catalyst to afford (Z)-alkylidenefuranones.Figure optionsDownload as PowerPoint slideHighlights
► Pd/C catalyzes Sonogashira-coupling followed by cyclization.
► Coupling between β-bromo-α,β-unsaturated carboxylic acids and terminal alkynes.
► Regioselective 5-exo-dig cyclization of β-alkynyl-α,β-unsaturated carboxylic acids.
► A new route for (Z)-alkylidenefuranones from readily available starting ketones.