Influence of alkali metal salts in an eluent for reversed phase HPLC separation of transition metal chelates with carbodithioate having an aza-crown ring

A chemical compound (A18CC) with a carbodithioate unit and an aza-crown ring in one intramolecule was synthesized, and reversed phase high performance liquid chromatography of the transition-metal chelates of A18CC was examined. The retention time of these A18CC chelates decreased along with an increase in the methanol fraction in the eluent. The retention time of the chelates decreased along with an increase in the concentration of alkali metal salt added to the eluent. The degree of the effect was Na+ > K+ >> NH4+. Li+ and the alkaline earth metal ions hardly had any influence. Since the chelates had charge by taking in the alkali metal ion in the aza-crown ring, this behavior was generated.