Molecular Diversity of 1,3‐Dipolar Cycloaddition of Quinolinium Ylides with Isatylidene Malononitriles.

Abstract: Triethylamine promoted cycloaddition reaction of N‐alkoxycarbonylmethylquinolinium bromide with isatylidene malononitriles afforded diastereoisomeric spiro[indoline‐3, 2′‐pyrrolo[1, 2‐a]quinolines] in satisfactory yields. The similar 1,3‐dipolar cycloaddition with N‐(p‐nitrobenzyl)quinolinlium bromide gave spiro[indoline‐3, 2′‐pyrrolo[1, 2‐a]quinolines] in good yields and with high diastereoselectivity. More importantly, the sequential cycloaddition reaction and oxidation reaction with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) resulted in novel 2‐(2‐oxoindolin‐3‐ylidene)‐2‐(2‐(dicyanomethylene)quinolin‐1‐yl)acetates. [ABSTRACT FROM AUTHOR]