Preparation of 1-aryl-substituted isoindoline derivatives by sequential Morita-Baylis-Hillman and intramolecular Diels-Alder reactions

Aldimines underwent Morita-Baylis-Hillman reactions with dienes activated by sulfonyl or nitrile groups. The N-allyl or propargyl derivatives of the products were subjected to intramolecular Diels-Alder cycloadditions to produce the corresponding partly saturated 1-arylisoindoline derivatives. The cycloadducts in the nitrile-activated N-propargyl series were aromatized by base-mediated elimination of HCN to afford 1-arylisoindolines, which were in turn oxidized to the corresponding 3-arylisoindolin-1-ones.