Synthesis of Calix[4]arene-Crown-6 with Alkoxysilyl-Containing Substituents.

An efficient procedure has been proposed for the synthesis of calix[4]arene-crown-6 conjugate having triethoxysilyl fragments in the para positions. The calixarene fragment adopts a 1,3-alternate conformation. Unlike known methods of synthesis of analogous structures, the proposed procedure ensures introduction of two ethoxysilyl groups into the oppositely located benzene rings in the macrocycle.