Isoquinoline frameworks via aryl radical-initiated 1,6-cyclization

Article abstract of DOI:10.1016/0040-4039(90)80216-9

Exclusive 1,6-cyclization occurred to afford isoquinoline frameworks when the enamide and the enamine substrates bearing exo-olefin moiety were treated with tri-n-butyltin hydride in the presence of radical initiator (9a, b → 12a, b; 13a, b → 18a, b), respectively. On the other hand, competitive 1,6- and 1,5-cyclization occurred to give a mixture of isoquinolone and isoindolone frameworks when the enamide substrates bearing endo-olefin moiety were treated under the same conditions (22a, b → 26a, b and 27a, b).