Access to functionalized isoquinoline N-oxides via sequential electrophilic cyclization/cross-coupling reactions

Electrophilic cyclization of 2-alkynylbenzaldoximes with various electrophiles leads to the formation of 4-iodoisoquinoline N-oxides or 4-bromo-isoquinoline N-oxides under mild conditions. The reaction can be transferred to highly functionalized isoquinoline N-oxides via palladium-catalyzed cross-coupling reactions.