An efficient solvent-free synthesis of 2-(alkylamino)-2-oxo-1-arylethyl-6,12-dioxo-6,12-dihydroindolo[1,2-b]isoquinoline-11-carboxylate derivatives via four-component reaction.

A one-pot approach for the synthesis of a new series of 2-(alkylamino)-2-oxo-1-arylethyl-6,12-dioxo-6,12-dihydroindolo[1,2-b]isoquinoline-11-carboxylate derivatives via a four-component reaction using isatin, homophthalic anhydride, cyclohexyl isocyanide and an aldehyde is described. This method has several advantages such as being catalyst- and solvent-free reaction and a high-efficiency process with high to excellent yields.