Binary and ternary complexes of copper(II) with N-phosphonomethylglycine and valine

The complex formation in binary and ternary systems containing copper(II), N-phosphonomethylglycine (H3PMG) and valine (HVal) have been investigated by potentiometry and Vis spectrophotometry at 25 °C. The complex species formation CuPMG, Cu(PMG)24−, Cu(HPMG)−, Cu(HPMG)22−, CuPMG(HPMG)3−, Cu(H2PMG)+, Cu(HPMG)(H2PMG)− were found in the binary system Cu2+-H3PMG and their stability constants were determined. The formation of the Cu(PMG)Val2− and Cu(HPMG)Val− species was estimated in ternary system and their structure was proposed.