New Kemp's Diacid Derivatives Give Efficient Transport and Modifiable Selectivity for Alkaline Earth and Transition Metal Ions

Article abstract of DOI:10.1246/bcsj.70.1895

New derivatives of 1,3,5-trimethyl-r-1,c-3,c-5-cyclohexanetricarboxylic acid (Kemp's triacid) showed high efficiency for alkaline earth and transition metal ion transport through a chloroform liquid membrane.Simple syntheses from Kemp's triacid or its geometric isomer provided chelating agents with a tripodal binding site for metal cations.The tripodal binding site consisted of r-1,c-3-diaxial carboxyl group and a c-5-amide, ester, or C-methyl group.Alkaline earth metal transport was quite variable and sensitive to c-5-group changes.For transition metal transport, c-5-amide diacids gave high total transport efficiency.For c-5-ester or C-methyl diacids, complexation of smaller divalent cations was decreased, resulting in increased selectivity for large cations.