Halogenation using quaternary ammonium polyhalides. Part 22. Selective bromination of aromatic ethers with benzyltrimethylammonium tribromide

The reaction of aromatic ethers with a stoicheiometric amount of benzyltrimethylammonium tribromide in dichloromethane–methanol or acetic acid–ZnCl2 under mild conditions gave, selectively, mono-, di-, or tri-bromo-substituted aromatic ethers in quantitative yields.