Mild base-promoted benzannulation for the construction of polyfunctionalized m-terphenyl derivatives and their application as potent UV-filters

A simple and facile transition-metal-free benzannulation was developed for the construction of polyfunctionalized m -terphenyl derivatives in good to excellent yield starting from 3-formyl chromones and 1,3-diaryl-2-propanones under a mild base. This protocol proceeds via domino Knoevenagel/intramolecular Michael addition/ring opening/aromatization. As an extension of this protocol, the synthesized m -terphenyl derivatives were evaluated as potent UV-filters.