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Salen-type ligands with electron-accepting substituents on the aromatic ring were synthesized. These ligands were used as extractant agents in polymeric inclusion membranes for the extraction of metal ions from aqueous solutions. Measurements of the membrane potential indicated selectivity of the membrane, which was confirmed by the quantification of the extracted metal. Ten types of metal ions were studied to establish the selectivity of each membrane. Salen-type ligands had higher selectivity to gold than to other metals and allowed for the extraction of acceptable percentages of this metal. The results showed that the percentage of extracted gold depends on the type of substituent present in the ligand's aromatic ring, the pH of the working solution and the area of the membrane. There was no effect of membrane thickness on the metal extracted. The time required to reach a certain extraction percentage decreased considerably as the membrane area increased. [ABSTRACT FROM AUTHOR]

We aimed to synthesize and characterize novel salen/salophen capped polymeric complexes including oxirane groups. For this purpose, we used 2,4,6-trichloro-1,3,5-triazine (I) as starting material. 2,4-dichloro,6-(3,4-dihydroxyphenylethylamino)-1,3,5-triazine (II) was synthesized by the reaction of an equivalent (I) and an equivalent dopamine. 2-(3,4-bis(oxiran-2-ylmethoxy)phenethyl)amine,4,6-dichloro-1,3,5-triazin (III) was synthesized by the reaction of two equivalents of epichlorohydrin and an equivalent of (II). [(Salen/Salophen) (Cr(III)/Fe(III))] capped complexes of (III) were synthesized by reaction of the reactants, codded as IV, V, VI and VII. Then, these monomeric complexes were polymerized by using ethylenediamine and o-phenylenediamine in 1,4-dioxane media, codded as VIII, IX, X, XI, XII, XIII, XIV and XV. II and III, monomeric and polymeric complexes were characterized by means of elemental analyses, 1H-NMR (spectrometry) and 13C-NMR (spectrometry), FT-IR spectrometry, ESI-MS and thermal analyses. Metal content in the prepared polymeric complexes was determined by inductively coupled plasma atomic emission spectrophotometer (ICPAES). We also synthesized novel polymeric complexes and investigated their effects on magnetic behaviors of [Cr(III)/Fe(III)(salen/salophen)] capped complexes. The complexes were determined to be low-spin distorted octahedral Fe(III) and distorted octahedral Cr(III). [ABSTRACT FROM AUTHOR]

Eight new trinuclear Fe(III)/Cr(III) complexes involving tetradentate (NO) and pentadentate (NO) Schiff bases of (salenH), (salophenH), (saldetaH) and (salpyrH) with 2,4,6-tris(4-carboxymethylenephenylimino-4′-formylphenoxy)-1,3,5-triazine were synthesized. The structure of ligand and complexes were identified using elemental and thermal analysis, magnetic susceptibility, and LC-MS, ICP-AES, H NMR and FT-IR spectral data. All complexes are tripodal-trinuclear. The complexes are low-spin (S = 1/2) distorted octahedral salen- or salophen-capped Fe(III), high-spin (S = 5/2) distorted octahedral saldeta- or salpyr-capped Fe(III) and distorted octahedral (S = 3/2) salen-, salophen-, saldeta- or salpyr-capped Cr(III). [ABSTRACT FROM AUTHOR]

2,4,6-Trichloro-1,3,5-triazine (cyanuric chloride, CNCl, 1) was used as the starting material. 2-(4-Carboxyphenylamino)-4,6-dichloro-1,3,5-triazine ( 2) was obtained from the reaction of cyanuric chloride with 4-aminobenzoic acid in the presence of sodium bicarbonate in acetone. A mononuclear complex ( 4) was obtained by reacting 2 and [FeSalen]O (3). A series of polymeric compounds was obtained by reacting 4 with a series of diamines. The polymeric complexes were characterized by elemental analysis, AAS, FT-IR, H NMR, TGA and magnetic susceptibility measurements. The complexes are low-spin, distorted octahedral Fe(III) species that are bridged by carboxylic acids. The [FeSalen]-containing compounds may have the electronic structure te. All the complexes have six coordination and are polymeric. [ABSTRACT FROM AUTHOR]

In this study, by using previously reported monomer complexes [(2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenFeIII)], [(2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenCrIII)], [(2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenFeIII)] and [(2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine)(salen/salophenCrIII)] obtained by Uysal and Uçan (J Inc Phenom Macrocycl Chem, in press), sixteen new polimer Fe(III) and Cr(III) complexes involving tetradentate Schiff bases N,N′-bis (salicylidene)ethylenediamine-(salenH) or bis(salicylidene)-o-phenylenediamine-(salophenH) with 2-(4-carboxybenzimino)-4,6-diamino-1,3,5-triazine or 2-(3,4-dihydroxybenzimino)-4,6-diamino-1,3,5-triazine (Uysal and Uçan, J Inc Phenom Macrocycl Chem, in press) and terephthaldehyde or glutaraldehyde have been synthesized and characterized by means of elemental analysis, H N.M.R., FT-IR spectrscopy, MS, thermal analyses and magnetic susceptibility measurements. The complexes have also been characterized as low-spin distorted octahedral Fe(III) and Cr(III) bridged by catechol and/or COO groups. [ABSTRACT FROM AUTHOR]

Schiff base metal complexes are a class of compounds that have been studied extensively because of their attractive chemical and physical properties, and their wide-ranging applications in numerous scientific areas. Researchers have incorporated Schiff base complexes into polymers, generating new materials with useful mechanical, thermal, chemical, and electronic properties. This work comprehensively reviews the developments in macromolecules containing Schiff base metal complexes, emphasizing new synthetic strategies and characterization techniques that were used to prepare and study these polymers. [ABSTRACT FROM AUTHOR]