PRODUCTION OF 5-BROMO-6-METHOXY-1-NAPHTHALENE CARBOXYLIC ACID

摘要

PURPOSE: To obtain a compound useful as an intermediate for synthesizing a therapeutic medicine for diabetic complications by oxidizing an easily available 6-methoxy-1-alkylnaphthalene with air in a liquid phase. CONSTITUTION: A method for producing 5-bromo-6-methoxy-1-naphthalene carboxylic acid comprises oxidizing (A) a 6-methoxy-1-alkylnaphthalene and/or its oxidation intermediate with (D) molecular oxygen in the presence of (C) a catalyst comprising a heavy metal compound and a bromine compound in (B) a solvent containing an aliphatic carboxylic acrid. The component A is preferably 6-methoxy-1-methylnaphthalene. The bromine compound of the component C is preferably used in an amount of 0.1-1.0 gram atom per mole of the component A. On the reaction, bromine is preferably added to the oxidation reaction solution after the oxidation reaction to cause a bromination reaction.