Synthesis of 2-((2-(Benzo[d]oxazol-2-yl)-2 H -imidazol-4-yl)amino)-phenols from 2-((5 H -1,2,3-Dithiazol-5-ylidene)amino)phenols through Unprecedented Formation of Imidazole Ring from Two Methanimino Groups.

A new synthetic pathway to four substituted imidazoles from readily available 2-((4-aryl(thienyl)-5 H -1,2,3-dithiazol-5-ylidene)amino)phenols has been developed. Benzo[ d ]oxazol-2-yl(aryl(thienyl))methanimines were proved as key intermediates in their synthesis. The formation of an imidazole ring from two methanimine derivatives likely includes the opening of one benzoxazole ring followed by ring closure by intermolecular nucleophilic attack of the N -methanimine atom to a carbon atom of another methanimine.