ChemInform Abstract: An Efficient One-Pot Four-Component Synthesis of 5H-Spiro[benzo[7,8]chromeno [2,3-c]pyrazole-7,3′-indoline]-2′,5,6(9H)-trione Derivatives Catalyzed by MgCl2

An efficient one-pot synthesis of 5H-spiro[benzo[7,8]chromeno[2,3-c]pyrazole-7,3′-indoline]-2′,5,6(9H)-trione derivatives via a four-component reaction of hydrazine hydrate, β-keto esters, isatins, and 2-hydroxynaphthalene-1,4-dione catalyzed by MgCl2 in ethanol is reported. This reaction provides the advantages of excellent yields, environmental friendliness solvent, simple workup procedure, and short reaction time.