We developed a visible-light-mediated, three-component annulation strategy for synthesizing 2,3-disubstituted quinazolin-4(3H)-ones from easily available starting materials under mild reaction conditions. Phenylthiourea intermediates, generated in situ from phenyl isothiocyanates and substituted anilines, undergo formal 4 + 2 annulation with isatins to afford the corresponding products. This process involves two C-N bond formations in a one-pot, two-step protocol. Crucially, the method requires no photocatalysts, transition metals, or external oxidants.
Lu et al. (Wed,) studied this question.