Facile synthesis of 3,3-diallyl isoindolones via a indium-mediated double allylation of ortho-cyanobenzoates

Various 3,3-diallyl isoindolones were synthesized via a indium-mediated Barbier type double allylation reaction of ortho-cyanobenzoates in good yields in short time. The reactivity of nitrile group toward allylindium is sufficient to form a cyclic compound when a suitable electrophilic center is present in the same molecule to trap the imine intermediate.