The “paco” or “alt” isomers of acetoxylcalixarenes were selectively prepared in the presence of catalytic amount (2 mol%) of Bi(OTf)3,. Calix[4]arenes selectively gave two different isomers under specified conditions with a good selectivity, but, calix[6]arenes and calix[8]arenes only gave the “alt” isomers with a high selectivity.