A one-pot, four-component reaction for the ef?cient synthesis of novel spiro[indeno[2,1-b]quinoxaline-11,
-pyran]-2
0
-amines by using InCl
is described. The syntheses are achieved by reacting ninhydrin with 1,2diaminobenzenes
to give indenoquinoxalines, which are trapped in situ by alkyl malonates and various
-methylencarbonyl compounds through cyclization, providing multifunctionalized spiro-substituted indeno
,1-b]quinoxaline-11,4
0
-pyran-2
0
3
-amines.