Phosphine-catalyzed ring-opening reaction of cyclopropenones with dicarbonyl compounds.

We developed a phosphine-catalyzed ring-opening reaction of cyclopropenones with dicarbonyl compounds as C -nucleophiles, leading to 1,3,3'-tricarbonyl compounds. During this neutral procedure, C -acylation is more dominant than O -acylation. This transition-metal free procedure features mild and neutral reaction conditions with good atom economy. As such, it represents a facile pathway to access 1,3,3'-tricarbonyl derivatives.