A simple and ef ficient method is proposed for the synthesis of tetrahydrobenzo[b]pyrans with aromatic aldehydes, active methylene compounds, and dimedone using basic ionic liquid catalyst in water. The procedure offers several advantages including short reaction time, good yield, easy procedure, and good recyclability of catalysts, which may be a practical alternative to conventional processes for preparation of 4-hpyrans.
An efficient method has been developed for the cascade synthesis of azo[1,2-a]indolones from azoles and2-fluoroaldehydes based on an iron-catalyzed S_NAr and a direct acylation reaction.A number of azo[1,2-a]indolones containing different azole rings and substituents were obtained in good yields.
