Strongly chelated metal complex

Strong chelating or complexing agents may form anionic complexes with metals. These anionic complexes can be separated by anion-exchange chromatography. Continuing with the chromium example, Cr(III) can be converted to an anionic complex... 

The complexers maybe tartrate, ethylenediaminetetraacetic acid (EDTA), tetrakis(2-hydroxypropyl)ethylenediamine, nittilotriacetic acid (NTA), or some other strong chelate. Numerous proprietary stabilizers, eg, sulfur compounds, nitrogen heterocycles, and cyanides (qv) are used (2,44). These formulated baths differ ia deposition rate, ease of waste treatment, stabiHty, bath life, copper color and ductiHty, operating temperature, and component concentration. Most have been developed for specific processes all deposit nearly pure copper metal. 

Many hydroxyp5rranones and hydroxypyridinones and their metal complexes have been of importance in analytical chemistry, solvent extraction, and metal separation. Here their excellent chelating properties in conjunction with the possibility of synthesizing strongly lipophilic derivatives make this class of ligands particularly useful. 

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