Study On Enaminones Based Domino Reaction

The cascade reaction of enaminones is one of the hotspots in organic synthesis.It has been widely used to construct heterocyclic skeleton and develop new drugs.In this paper,we have been developed various types cascade reaction based on enaminones,and successfully constructed pyrroloquinolines,spirooxindoles and ?-halogenated N-aryl enaminones.The result of this paper mainly included the following aspects:First,An efficient and facile synthesis of pyrrolo[3,4-c]quinoline-l-ones by TMSCl-catalyzed reaction of easily available substituted isatins and ?-enamino ketone derivatives has been developed.This cascade reaction has shown good functional group tolerance,operational simplicity,and proceeded smoothly in good to excellent yields via one step under mild conditions.The preliminary experiments to oxidative cleavage of the C=C bond have been applied.We found and established a new synthetic strategy to construct the construction of 1,3-di carbonyl pyrroloquinoline compounds.Next,a Bronsted acid-controlled protocol is described for the efficient catalysis of two different reactions,namely acylation cascade-and[1+2+3]-type cyclization of enaminones and isatins for the concise synthesis of highly functionalized pyrrolo[3,4-c]quinolin-l-ones and spirooxindoles in the presence of carboxylic acids and KHSO4,respectively.The observed chemoselectivity was reasonably,explained by trapping the intermediate a,(3-unsaturated 2-oxindoles,and the source of the hydroxyl group,carbocation intermediate.Finally,a new method for the selective synthesis of a-halogenated N-aryl enaminones was studied and established by the active reaction of the activated carbonyl groups at the carbonyl group a based on the enamidones.The reaction was carried out only under the catalysis of CuX2(X = Cl,Br).