Synthesis and characterization of new macrocyclic schiff bases by the reaction of: 1,7-Bis (6-methoxy-2-formylphenyl)-1,7-dioxaheptane and their use in solvent extraction of metals

Two new macrocyclic Schiff bases (II) and (III) containing nitrogen–oxygen donor atoms were designed and synthesized by reaction between diethylene triamine or 2,2′-(ethylenedioxy) bis (ethylamine) and the intermediate compound: 1,7-bis (6-methoxy-2-formylphenyl)-1,7-dioxaheptane (I). Identification of these macrocyclic Schiff bases: 1,15,18,21,35,38-hexaaza-7,9; 27,29-dibenzo-[3,4;12,13;23,24;32,33-tetra-(6′-methoxy phenyl)]-5,11, 25,31-tetraoxacyclotetracontan-1,14,21,34-tetraene. (II) 1,15,24,38-Tetra aza-7,9; 30,32-dibenzo-[3,4;12,13;26,27;35,36-tetra-(6′-methoxy phenyl)]-5,11,18,21,28,34,41,44-octaoxacyclo-hexatetracontan-1,14,24,37-tetraene. (III) was determined by (LC–MS), (IR), (1H NMR) spectroscopy, and microanalysis (C,H,N). The liquid–liquid extraction of metal picrates, such as Ag+, Cu2+ and Ni2+ from aqueous phase to organic phase was carried out using the novel ligands. The effect of chloroform and dichloromethane as organic solvents over the metal picrate extractions was investigated at 25 ± 0.1 °C by using atomic absorption spectrometer. The composition of the extracted Ag+ complex was (1:2) (L:M) and Cu2+ complex was (1:1) (L:M) for ligand (III).