| abstract |
The anthranilic acid derivatives of the formula wherein R 1 , R 2 and R 3 each independently represent hydrogen, lower alkyl, lower alkoxy, carboxyl, chlorine, fluorine or phenyl which is optionally substituted by lower alkyl or lower alkoxy, and R. lower alkyl or phenyl, can be prepared by carbonylation of corresponding 2-bromo- or iodoacetanilides in the presence of a catalyst from palladium and a tertiary phosphine in an aqueous reaction medium containing a trialkylamine. They can be converted into the corresponding anthranilic acids by basic hydrolysis. These compounds are valuable intermediates in the synthesis of active pharmaceutical ingredients, for example pyridoquinazolines, which have valuable anti-allergic properties. |