A New Avenue to One-Pot Four-Component Synthesis of Spiro[indoline-3,4'-quinoline] Derivatives Using DABCO as a Green Catalyst

A simple, efficient, and green, one-pot four-component synthesis of spiro[indoline-3,4 '-quinoline] derivatives has been developed from isatin, ethyl cyanoacetate/malononitrile, dimedone, and aniline using green catalyst DABCO and green solvent ethanol. The current method generates good to exceptional yields in a short reaction time and provides a broad substrate scope. This method also works for gram scale reactions.

Automated summary

A simple, efficient, and green method has been developed for the synthesis of spiro[indoline-3,4'-quinoline] derivatives. The method uses isatin, ethyl cyanoacetate/malononitrile, dimedone, and aniline as starting materials, with the green catalyst DABCO and green solvent ethanol. The method provides good to exceptional yields in a short reaction time and has a broad substrate scope, including gram scale reactions.