Convenient Synthesis of Spirooxindole-Fused Pyrazolopyridine Derivatives

摘要

Concise and efficient three-component domino reaction for the synthesis of spirooxindole fused pyrazolopyridine derivatives has been established. This domino reaction is a green process and can be easily performed in water by using readily available substrates. The present strategy shows attractive characteristics, such as convenient one-pot operation, inexpensive and reusable solid acid catalyst, without time-consuming syntheses and avoiding tedious work-up or purification procedure. A probable mechanism accounting for the reaction is proposed.