Catalyst- and Additive-Free Decarboxylative C-4 Phosphorylation of Coumarin-3-Carboxylic Acids at Ambient Conditions

A catalyst- and additive-free practical and green synthetic strategy for decarboxylative C-4 phosphorylation of coumarin-3-carboxylic acids, for the first time, has been accomplished to access a series of substituted 4-(diarylphosphoryl)chroman-2-ones at ambient conditions. The developed protocol is successfully applied to large-scale synthesis.