A visible-light-mediated metal-free oxidation of 1-benzyl-3,4-dihydroisoquinolines
(1-BnDHIQs) for the switchable preparation of a wide range of 1-benzoylisoquinolines
(BzIQs) and 1-benzoyl-3,4-dihydroisoquinolines (BzDHIQs) is realized using dioxygen
as the oxidant. This protocol provides a facile route for the efficient synthesis
of isoquinoline alkaloids. Mechanistic investigations suggest that a radical pathway
and an ionic pathway may exist simultaneously, with both pathways proceeding via a
common key peroxide intermediate to give the oxidized products.
Key words
visible light - 1-benzoylisoquinolines - 1-benzoyl-3,4-dihydroisoquinolines - metal-free
- dioxygen
