Tetraalkylated 2,8,14,20-tetrathiacalix[4]arenes: Novel infinite channels in the solid state

Pavel Lhoták, University of Chemistry and Technology, Prague
Michal Himl, University of Chemistry and Technology, Prague
Svetlana Pakhomova, University of Chemistry and Technology, Prague
Ivan Stibor, University of Chemistry and Technology, Prague

Abstract

The synthesis of new tetraalkylated derivatives of 2,8,14,20- tetrahiacalix[4]arenes was achieved by the refluxing of thiacalixarenes in acetone or acetonitrile with the alkylation agent (R-I, R-Br) in the presence of K2CO3 or Cs2CO3. The structure of the tetraalkylated thiacalix[4]arenes was studied by means of H NMR experiments proving the 1,3- alternate conformation under measurement conditions (CDCl3, room temperature). The same conformation was established by X-ray analysis in the solid state where these derivatives create nice infinite channels.