Formazan 3-carboxy

More recent work117 has brought to light other, surprising, differences between l-(2-carboxy-phenyl- and l-(2-hydroxyphenyl)-formazans and cast some light on the structures of their copper complexes. Like 1,3,5-triphenylformazan, both l-(2-carboxyphenyl)- and l-(2-hydroxyphenyl)-... 

Metal-Containing Tridentate Formazans. Formazans substituted with OH or COOH in the 2-position of the N1- or Ns-aryl group have the same complexing properties as 2-hydroxy- (or carboxy)-2-aminodiarylazo dyes. Similarly, they also form 1 1 complexes with four-coordinate metals, and 1 2 complexes with six-coordinate metals. Being N ligands formazans react more readily with cobalt salts than with chromium salts. The mostly blue 1 2 cobalt(m) complexes of type 34 [72] and the mostly gray-blue complexes of type 35 [73] are known. 

METAL COMPLEXES OF AZO DYES Metal complexes of certain 0,0 -dihydroxyazo, 0-carboxy-0 -hydroxyazo, o -amino-o hydroxyazo, arylazosalicyclic acid, and formazan compounds are used as dyes for wool, nylon, and cotton with generally much improved washfastness and lightfastness properties when compared to their respective unmetallized precursors. Dyes that are chelated with the metal on the substrate during the dyeing process are termed metallizable or mordant dyes. Conversely, those dyes that have been metallized by the dye manufacturer prior to use by the dyer, are classified as premetallized dyes. The two important types of premetallized dyes are the 1 1 and 2 1 complexes, eg, complexes with 1 1 and 2 1 ligand-to-metal ratios, respectively. 

The Ni + cation shows little discrimination between ligands in propylene carbon-ate. 2 Kinetic parameters have been communicated for reactions of Ni-+ and Co + with ammonia in aqueous methanol and for Ni + with ethylenediamine or 2,2 -bipyridyl in aqueous dimethylformamide, and with 2,2 -bipyridyl derivatives in aqueous ethanol. The kinetics of reaction of Fe + with benzoylacetanilides have also been studied in aqueous ethanol the kinetic pattern for reaction of Fe + with thiocyanate in aqueous carboxylic acids is complicated by parallel complex formation with solvent-derived carboxylate. Copper(ii)-formazan (2) chelate complex formation has been shown to take place in discrete steps in aqueous ethanol. Carboxy-late anion effects on the copper(ii)-tetraphenylporphine reaction have been studied in dimethylformamide. ... 

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