VERFAHREN ZUR HERSTELLUNG VON 4H-3,1-BENZOXAZIN-4-ONEN

摘要

Production of 4H-3,1-benzoxazine-4-ones of formula (I) in which: R<1> is hydrogen, C1-C4-alkyl, C1-C4-alkoxy, carboxyl, sulpho, nitro or halogen; R<2> is C1-C20-alkyl, phenyl or phenylalkyl with 1 to 4 C atoms in the alkyl group, whereby a phenyl nucleus may be substituted by one or two C1-C4-alkyl groups, C1-C3-halogen alkyl groups, C1-C4-alkoxy groups, C1-C3-halogen alkoxy groups, C1-C4-alkyl mercapto groups, C1-C3-halogen alkyl mercapto groups, carboxyl groups, sulpho groups, C1-C4-alkyl sulphonyl groups, C1-C3-halogen alkyl sulphonyl groups, nitro groups or halogen atoms; and n is 1 or 2; by the reaction of isato acid anhydrides of formula (II) with acyl halides of formula (III) in which X is chlorine or bromine, by conducting the reaction at an outside temperature of 215 to 280 DEG C and causing the reaction components (II and III) to react together for at least 4 hours at this temperature.