Copper-Catalyzed Decarboxylative Phosphorylation of Coumarin-3-carboxylic Acids

Abstract We report a novel, efficient, one-pot, copper-catalyzed, decarboxylative strategy for the cross-coupling of coumarin 3-carboxylic acids with H-phosphonates. The approach involves a decarboxylation followed by phosphonation through a radical pathway, and uses an inexpensive copper catalyst. Optimizations were carried out using various copper catalysts, oxidants, and solvents. The reaction is highly effective, with a broad functional-group tolerance, and affords good to excellent yields. This transformation provides a versatile and useful synthetic pathway for the construction of bioactive scaffolds with valuable C–P bonds.