Quadruple Click: A Facile Pathway leading to Tetrakis(4-(1,2,3-triazolyl)methyl)-ethylenediamine Derivatives as a New Class of Extracting Agents for Soft Metal Ions

Tetrakis(triazolylmethyl)ethylenediamine, which is a class of tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) analogue, is synthesized by a quadruple click reaction of tetrapropargylated ethylenediamine and four equivalents of alkyl azide. The obtained compound efficiently extracted the soft metal cadmium(II) ions by solvent extraction. It is also found that an N-isopropylacryl amide (NIPA) gel using the triazole ethylenediamine as a cross-linker exhibits a temperature-dependent extraction performance.