A novel skeletal remodeling strategy to transform chalcone-based pyridinium salts into structurally intriguing polycyclic isoindolines was achieved through a dearomative ring-opening/ring-closing sequence.

A highly diastereoselective dearomative trifunctionalization of pyridinium salts with multifunctional o-hydroxyl aromatic azomethine ylides has been established, which not only provided a convenient and rapid method to assembly challenging and...

We report an unexpected dearomative periphery modification strategy for transforming quinolinium salts into structurally crowded pyrrolidine–tetrahydroquinoline polycyclic systems with complete regio- and diastereoselectivity. Importantly, the reaction pathway was regulated by simply tuning the substituents, achieving substituent-directed divergent synthesis. The notable features of this transformation include readily available starting materials, green conditions, a simple workup procedure, high bond- and ring-forming efficiency, and substituent-directed diverse synthesis.

We report an efficient alkyl transfer strategy for the direct β-alkylation of chalcones using commercially available alkyl bromides as alkyl reagents. In this transformation, the ortho-phosphanyl substituent in the chalcones is crucial for controlling their reactivity and selectivity. It also serves as a reliable alkyl transfer shuttle to transform electrophilic alkyl bromides into nucleophilic alkyl species in the form of quaternary phosphonium salts and transfer the alkyl group effectively to the β-position of the chalcones. This alkyl transfer strategy can be further extended to the alkenylation of ortho-phosphanyl benzaldehydes to assemble functionalized polyenes.