Abstract In the presence of methanesulfonic acid as catalyst, the condensation reactions of 5, 5′-dialkyldipyrromethanes with p-hydroxyacetophenone in methanol resulted in a mixture of the unexpected polysubstituted 15α, 20α-di (4-hydroxylphenyl) calix [4] pyrroles and the expected 10α, 20β-di (4-hydroxylphenyl) calix [4] pyrroles in comparable lower yields. The crystal structures of the new calix [4] pyrroles and their oxyacetate derivatives ...
