An Efficient Optimization, In Situ Reduction and Cyclization Reaction for the Synthesis of Functionalized Pyrazolo[3,4-f]quinolines Derivatives

摘要

An efficient and novel method for the synthesis of pyrazolo[3,4-f]quinoline derivatives by an efficient in situ reduction and cyclization reaction of 6-nitro-1H-indazole, aromatic aldehydes, and 4-hydroxy-2H-chromen-2-one or barbituric acid has been developed. Compared with amino compounds, nitro compounds are easier to obtain and more stable. The synthesis was achieved by using a multicomponent procedure under Fe/H2O medium. The advantages of this method are mild conditions, operational simplicity, high yields, and wide range of substrates.