Synthesis of spiro[indoline-3,4'-pyrano[3,2-c]quinolone]-3'-carbonitriles

摘要

Quinoline-2,4-diones reacted with 2-(2-oxo-1,2-dihydroindol-3-ylidene)malononitrile in pyridine to give 2'-amino-2,5'-dioxo-5',6'-dihydrospiro(indoline-3,4'-pyrano[3,2-c]quinoline)-3'-carbonitriles in good to excellent yields. The structures of all new products were proven using one- and two-dimensional NMR, IR, and mass spectral data, and in five cases X-ray structural analyses. The possible mechanism for the reaction is also discussed.