Synthesis of Tetraoxacalixarenes Based on Ethyl Pentafluorobenzoate. Effect of Solvent Polarity and Nature of the Base

The direction of reaction of ethyl pentafluorobenzoate with orcinol depends largely on the polarity of the solvent and the nature of the base. In acetonitrile the reaction proceeds exclusively in the para-position of ethyl pentafluorobenzoate, while in the dioxane–Na2CO3 system the products of substitution of fluorine atoms in the ortho-position are predominantly formed. The reaction of triphenyl with orcinol in the dioxane–K2CO3 system leads to the formation of a mixture of possible fluorine-containing isomeric tetraoxacalixarenes. The corresponding fluorine-containing tetraoxacalixarenes with carboxyl group were obtained by hydrolysis of ester groups.