Aza-Conjugate Addition Methodology for the Synthesis of N-Hydroxy-isoindolin-1-ones

Aryl-aldehydes containing ortho-substituted propiolate fragments react with hydroxylamine to afford carbinolamine intermediates that undergo intramolecular aza-conjugate addition reactions to afford N-hydroxy-2.3-dihydro-isoindolin-l-ones that can be reduced to their corresponding isoindolin-l-ones and isoindoles.