A simple synthetic protocol was developed for the efficient synthesis of functionalized 3-{1-[2-(1H-indol-3-yl)ethyl]-4,5,6,7-tetrahydro-1H-indol-3-yl}indolin-2-ones in high yield via three-component reaction of tryptamine, dimedone, and 3-phenacylideneoxindoles in refluxing acetonitrile with p-toluenesulfonic acid as catalyst.
Key words
multicomponent reaction - β-enaminone - tryptamine - isatin - dimedone - indole