The selective introduction of one or two acetyl groups by direct replacement of tert-butyl groups via the ipso aromatic acetylation of meta-bridgedaromaticcompounds having two arene rings is described. Acetylation of syn- and anti-di-tert-butyl[n.2]metacyclophanes 3 (n=2,3,4) with acetyl chloride in the presence of TiCl4 gave the ipso-acetylation product at the tert-butyl group. However, only one