Alkylation and annulation of 3-(phenylsulfonyl)-2-alkyl-2,3- dihydroisoindol-1-ones

Article abstract of DOI:10.1016/S0040-4039(98)00293-7

The hydroxylactams obtained from reduction of N-substituted phthalimides were phenylthiated and oxidized to give 3-(phenylsulfonyl)-2,3- dihydroisoindol-1-ones. Deprotonation of the sulfones with sodium hydride followed by treatment with electrophiles gave substitution. Sulfones with suitably-disposed α,β-unsaturated ester groups gave cyclic products from intramolecular Michael addition. Desulfurization of the phenylsulfonyl intermediates was effected in quantitative yield using Raney nickel promoted by ultrasound.