Synthesis of Novel 2-(4-Arylthiophenyl)quinazolin-4(3H)-ones Using S-Arylation Reaction

Abstract 2-(4-Methylthiophenyl)quinazolin-4(3H)-one was prepared by condensation of 2-aminobenzamide with 4-methylthiobenzaldehyde in a two-step approach with isolation of the intermediate azomethine and subsequent dehydrogenation of the latter using DDQ. It was shown that the reaction of quinazolin-4(3H)-one with arynes, generated in situ from corresponding anthranilic acids, proceeds exclusively via an S-arylation pathway and leads to a series of previously unknown 2-substituted quinazolin-4(3H)-ones. A similar approach proved effective for the synthesis of 4-phenyl substituted 2-arylquinazolines, which expands the possibilities for modification of the quinazoline system. New quinazolines exhibit solid-state fluorescence with absolute quantum yield up to 10%, indicating their potential as functional luminescent materials.