Synthesis of 4-aryl-3,4-dihydrocoumarins and 4-aryl-4H-chromenes via Er(OTf)3-catalyzed cascade reactions of p-quinone methides with 1,3-dicarbonyl compounds

The Er(OTf)(3)-catalyzed cascade cyclization reaction of para-quinone methides (p-QMs) with various 1,3-dicarbonyl compounds has been developed, which efficiently constructed a series of versatile 4-aryl-3,4-dihydrocoumarins and 4-aryl-4H-chromenes. Herein, we not only propose a novel cyclization strategy of p-QMs, but also provide an easy access to structurally diverse coumarins and chromenes.

Automated summary

In this study, an Er(OTf)(3)-catalyzed cascade cyclization reaction of para-quinone methides (p-QMs) with various 1,3-dicarbonyl compounds was developed, leading to the formation of a series of versatile 4-aryl-3,4-dihydrocoumarins and 4-aryl-4H-chromenes. This work not only presents a novel cyclization strategy for p-QMs, but also provides a facile access to structurally diverse coumarins and chromenes.