An efficient approach to functionalized benzo[a]xanthones through reactions of 2-methyl-3-(1-alkynyl)chromones with electron-deficient chromone-fused dienes.

An efficient tandem process was developed to synthesize diversified benzo[a]xanthones from 2-methyl-3-(1-alkynyl)chromones with electron-deficient chromone-fused dienes. This unusual reaction, involving multiple steps and not requiring the use of transition metal catalysts or an inert atmosphere, results in the formation of three new C-C bonds and one C-O bond.