Mercaptocalixarenes as mercury(II) extractors: Synthesis, structural analysis and extraction properties of lipophilic dimercaptocalix[4]arenes

Lipophilic calix[4]arene derivatives that contain two O-C-12 alkyl chains a nd two SH groups at the lower rim were synthesized and characterized in the 1,2- and partial-cone conformations. Both conformers were treated with Hg2 + and formed neutral mononuclear Hg2+ complexes, in which the cation was li nearly coordinated to two sulfur atoms. The lipophilic dimercaptocalixarene s were shown to extract Hg2+ cations exclusively and efficiently from an aq ueous phase into chloroform.