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https://doi.org/10.1021/ja01166a044

has been cited by the following article:

• TITLE: Stoichiometry and Stability Constant Values for Copper (II) Chelates with Ethylene Diamine in Deep Eutectic Solvents (DES) (Ethaline) Solutions

  AUTHORS: Khalid El Ttaib, Abdolhadi Benhmid, Rifat Hasan Omar

  KEYWORDS: Cu(II), Ethylene Diamine (en), Deep Eutectic Solvents, Job’s Method, Ionic Liquids and Stability Constant

  JOURNAL NAME: Open Journal of Applied Sciences, Vol.14 No.9, September 26, 2024

  ABSTRACT: In this study we used the deep eutectic solvents (ionic liquids) to investigate the reaction between copper (II) with ethylene diamine (en). Two of the existing methods for analyzing spectrophotometric measurements have been applied for establishing, the stoichiometry and whenever possible, the stability constants of the chelates formed. The method of continuous variations was necessary to determine first whether, the metal ion and the ligand ethylene diamine form one or more than one chelate, when more than one chelate formed, the results obtained depend on the wavelength and for meaningful conclusions the wavelengths were carefully selected. The empirical formulae of the chelates were further substantiated by the molar ratio method. The effect of time and temperature on the formation and stability of these chelates in solution is also studied. The stability constants, K1 and K2 for the copper (II) chelates were calculated, though reliable, and are comparable to literature values.