Salicylic acid metal complexes

Using these agents, especially the particularly effective 1 2 complex 4 with salicylic acid, metallization can be carried out easily at high pH without precipitation of inert chromium hydroxide. In certain cases a 1 1 chromium complex that still contains chelating organic acid as ligand can also be obtained. 

Hok, B., Studies on the extraction of metal complexes. XV. The dissociation constants of salicylic acid, 3,5-dinitrobenzoic acid, and cinnamic acid and the distribution between chloroform-water and methyl isobutyl ketone (hexone)-water, Sv. Kem. Tidskr. 65, 182-194 (1953). 

Good non-colored negative charging CCAs have been obtained by making non-colored analogues of the 2 1 chromium complex azo dyes. This is achieved by making the metal complex of an aromatic ortho-hydroxy carboxylic acid. Typical examples are the chromium, aluminum, and zinc complexes of di-tert-butyl salicylic acid, e.g., BONTRON E-8136 41 (53) and BON-acid36,41,42 e.g., BONTRON E-82 (54). 

Synthetic alizarin (5.1), Cl Mordant Red 5 (5.2) and Cl Mordant Orange 1 (5.3), the first azo dye capable of forming a metal complex, in this case via the salicylic acid residue, are examples of the simple mordant dyes in widespread use at the time when Werner propounded his theory. The first metal-complex dyes to be prepared in substance, rather than within the fibre, were discovered by Bohn of BASF in 1912 by treating hydroxyanthraquinonesulphonic acids with a warm solution of a chromium(III) salt. In the... 

In a bidentate ligand system, three molecules of a dye containing either a terminal salicylic acid unit (as in 5.2) or an o-nitrosonaphthol residue are able to chelate simultaneously with a trivalent metal ion of CN6, such as chromium (III) or iron(III), to form a 1 3 metal-dye complex (as in 5.8). Historically, the most important bidentate ligand system was alizarin (5.1). It has been suggested that both hydroxy groups and the keto group in the peri position are all involved with the metal atom in the chelation mechanism. 

Salicylic acid has been found useful as a terminal coupling component in direct or mordant dyes to provide a bidentate site for metallisation. The free acid is also capable of complexing and ammonium chromisalicylate (5.12) is used as an intermediate in the synthesis of metal-dye complexes. Cl Mordant Orange 1 (5.3) and Yellow 5 (5.13) are examples of dyes... 

The electrostatic effect of the poly(4-vinylpyridine)-Cu(II) catalyst was also reported by Dadze et al. 115). Oxidation of ascorbic acid, salicylic acid, and tri-t-butylphenol was accelerated and that of p-phenylenediamine retarded by the poly(4-vinylpyridine) ligand at lower pH. As described in Section IIIA, a polymer-metal complex behaves as a polycation in aqueous solution, and the reaction is sensitive to the charge of low-molecular-weight species. The electrostatic effect due to the polycationic domain of a polymermetal catalyst is also predominant in the oxidation of charged substrates. 

The 2-hydroxybenzoic acid, normally called salicylic acid, is well known due to its medical applications, namely as an antipyretic and in the treatment of certain types of rheumatism. The biological action of this compound is connected4,5 with its ability to bind metal ions. Not only is the efficacy of the treatment increased, but toxicity problems related to the injection of salicylic acid are diminished by administering salicylate metal complexes. 

Terminally metallizable dyes (30) are obtained by the interaction of a diazonium salt and a coupling component containing a chelating system, for example salicylic acid, catechol, salicyl-aldoxime or 8-hydroxyquinoline, and their coordination chemistry is typical of these compounds. Such dyes were rarely used as preformed metal complexes but were usually applied to cotton and then converted to their copper complexes on the fibre to improve their fastness to wet treatments. A typical example is the blue dyestuff (31). 

The formation of these ternary luminescent lanthanide complexes was the result of displacement of the two labile metal-bound water molecules, which was necessary because the energy transfer process between the antenna and the Ln(III) metal centre is distance-dependent. This ternary complex formation was confirmed by analysis of the emission lifetimes in the presence of DMABA and showed the water molecules were displaced by a change in the hydration state q from 2 to 0, with binding constants of log fCa = 5.0. The Eu(III) complexes were not modulated in either water or buffered solutions at pH 7.4. Lifetime analysis of these complexes showed that the metal-bound water molecules had not been displaced and that the ternary complex was not formed. Of greater significance, both Tb -27 and Tb -28 could selectively detect salicylic acid while aspirin was not detected in buffered solutions at pH 7.4, using the principle as discussed for DMABA where excitation of the binding antenna resulted in a luminescent emission upon coordination of salicylic acid to the complex. 

Some investigators have shown that mixtures of succinimides, sulfonates, phenolates and salicylates produce acid-base complexes which tend to form aggregations (Inoue and Watanabe, 1983 Vipper and Watanabe, 1981). The intermolecular interactions between ashless dispersants (PIBS) and metallic detergents were found to decline in the following order ... 

Salicylic and cresotinic acids are used in the preparation of azo dyes and of tri-phenylmethane dyes of the aurine type (eriochrome azurol B). These acids confer upon the dyes the property of going onto metal mordants, particularly chromium mordants, and also of forming complex compounds, in substance, with suitable metal salts. Salicylic acid is also widely used in the pharmaceutical industry. 

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