Synthesis and Characterization of New Thiacalix[4]arenes Bearing Semicarbazide and Thiosemicarbazide Fragments at the Lower Rim

Starting from thiacalixarene tetraacetates, tetraacetohydrazides have been prepared and then used for the introduction of semicarbazide and thiosemicarbazide fragments into the lower rim by the reaction with phenyl isocyanate and phenyl isothiocyanate in dry toluene. The structures of the prepared compounds were investigated by FT‐IR, FAB‐MS, ¹H NMR, and X‐ray crystallography, and their receptor properties were examined by liquid liquid extraction of dichromate anions.