Synthesis Of Butenolides From Keto Acids And Synthesis Of Polycyclic Compounds From Ring-fused Benzocyclobutenols

Cyclic compounds are widely found in natural products,drugs and materials.Over the past decades,cyclization reactions have drawn the attention of chemists and made great progress.During the study of my Master degree,I focus on the synthesis of two kinds of cylic compounds---butenolides and polycyclic compounds.Synthesis of Butenolides from Keto Acids(1)In this part,we describe three efficient and practical approaches to highly substituted butenolides.One is about the synergistic acid-promoted synthesis of highly substituted butenolides via the annulation of keto acids and tertiary alcohols,and others are about the synthesis of highly substituted butenolides through the annulation of keto acids and alkynes.In contrast to metal catalysts,acids are cheap and low-toxic.Moreover,the concepts of environment benign and atom-economic progress are also embedded in these strategies.(2)Synthesis of Polycyclic Compounds from RBCBsIn this part,we introduce two novel methods to polycylic compounds.One is about the rhodium-catalyzed C-C bond olefination of ring-fused benzocyclobutenol and application in the construction of polycyclic pompounds,and another is about the palladium-catalyzed C-C bond arylation of ring-fused benzocyclobutenol and application in the construction of triphenylenes.In contrast to traditional strategies,our methods have high regioselectivity and afford the single product.Moreover,intramolecular cyclization avoids some cumbersome procedures.