A novel synthesis of 2-aminochromones via phosgeniminium salts

A novel method for the synthesis of antiplatelet 2-aminochromones making use of the reaction of 2'-hydroxyacetophenone-BF 2 complexes with phosgeniminium chlorides has been developed. Aqueous hydrolysis of the intermediate β-chlorovinylogous amide-BF 2 complex affords the 2-aminochromone in good yield, without the need for chromatographic purification