Inner-complex compounds

Copper(I) forms compounds with the anions of both strong and weak acids. Many of these compounds are stable and insoluble in water. Compounds and complexes of copper(I) are almost colorless because the inner >d orbital of the copper is completely filled. There is a very strong tendency for copper(I) to disproportionate in aqueous solutions into copper(Il) and metallic copper. 

In chelation complexes (sometimes called inner complexes when uncharged) the central metal ion coordinates with a polyfunctional organic base to form a stable ring compound, e.g. copper(II) acetylacetonate or iron(III) cupferrate ... 

Soon after the introduction of dimethylglyoxime as a specific reagent for nickel by Tschugaeff-Kraut-Brunck (1905-1907), Baudisch discovered a compound which precipitates copper and iron quantitatively from acid solutions.82 He appropriately named this reagent as cupferron . It is the water soluble ammonium salt of nitrosophenylhydroxylamine (5). When dissolved in chloroform, the whitish-grey copper compound gives a bright yellow solution and the brown yellow iron(III) compound a deep red solution. This behaviour reveals the inner complex character of these derivatives (6). 

DPCC are obtained on the basis of metal-containing ligands, which can be classical Werner complexes (Scheme 1.11), salicylaldiminates [140], and other inner-complex compounds, as well as numerous organometallic compounds [112,113,159] ... 

A change of salt anions allows us to carry out controlled syntheses of definite types of coordination compounds. Thus, metal halides are widely used to prepare molecular (Sec. 3.1.1.1) and ti-complexes (Sec. 3.1.1.3). Metal acetates are mostly applied in the syntheses of metal chelates and, especially, inner-complex compounds (Sec. 3.1.1.2). Di- and polynuclear structures are formed under use of the anions mentioned above, which, in some cases, determine (see Sec. 3.1.1.4) a type and donor centers of bridge fragments. At the same time, the mentioned approach to choice of salts of metal complex-formers has many exceptions, although it is useful. 

Additionally to the indicated chelates, other inner-complex compounds, for example those on the basis of hetarylformazanes (3.206) [448], can also take part in the examined template transformations ... 

George, P, and McClure, D. S. The Effect of Inner Orbital Splitting on the Thermodynamic Properties of Compounds and Complexes of the Transition Metals, in Cotton s Progress in Inorganic Chemistry, Vol. I, 381-464, Interscience Publishers, New York (1959). 

The preparation of drug complex compounds and the use of their qualitative properties have enormous importance in the pharmaceutical industry. Complex compounds have also taken part in the processes of the vital activity of humans as inner-complex compounds in hemoglobin, tissues, etc. (Fig. 3). Complex bound metals are important components of the ferments (in particular, the oxidative ferments). 

In view of the general objection to the term complex compound, it would be desirable to have an alternate expression for inner complex compound. For the purposes of this paper the expression inner coordination compound will be used. 

A series of inner complex salts of metals of the eighth subgroup is derived from the hydrogen compound H2N2S2, on which the lead compound (XXXIII) is based. The possibility of forming such complexes was first... 

Such metallic derivatives are inner complex compounds like those of the a-amino acids ... 

Nonelectrolytes. Whenever the coordination number (C.N.) of a metal atom is twice that of its oxidation state (O.S.), the chelate compound formed is a nonelectro-ljd or an inner complex compound of the first order. These are illustrated for the 2,4-pentanediono compounds ... 

In many pyroreactions, the solids give rise to products that appear as separate phases. But there are surface reactions which involve dissolved, fused or gaseous reactants and in these the reaction products remain in the phase associated with the solids. When this is the case, we are dealing with a chemical adsorption and the formation of adsorption compounds. In spot test analysis, special importance attaches to the chemical adsorption of dyestuffs, i.e. in those instances in which the structural inner complex salts formed are bound to metal hydroxides in their sol or gel form. The resulting "color lakes", which, in turn, contain metal chelate compounds, serve as the bases of exceedingly sensitive tests. 

Morin, the coloring matter of fustic, is 3,5,7,2, 4 -pentahydroxy flavone (I). Its alcohol solutions react with aluminum salts in neutral or acetic acid solution to give an intense green fluorescence in daylight and ultraviolet light. The fluorescence is due to the formation of a colloidally dispersed inner complex aluminum salt of morin with the probable structure (II), or to an adsorption compound of morin with alumina. Beryllium, indium, gallium, thorium and scandium salts also form fluorescent compounds with morin. The pH of the system has much influence in these reactions. The only metal ion whose reaction with morin is independent of pH is Zr+ or its hydrolysis product (compare page 519). 

I), the dye acid is precipitated. If, however, the system is neutralized before or after the introduction of the dye or made basic with ammonia, and then acidified with dilute sulfuric acid, and then shaken with ether, the ether layer becomes yellow and the water layer is red. The former contains the unused dye acid, the latter the inner complex aluminum-dyestuff compound... 

In view of its constitution, Alizarin Blue (I) might be expected to display the characteristics of alizarin (page 96) and 8-hydroxyquinoline (page 335). This is not the case, as shown by the facts that it is neither soluble in alkali as is alizarin nor in dilute acids as is oxine. Probably Alizarin Blue is a chelate compound as represented in (la). Solutions can be prepared in dioxane, pyridine, acetic anhydride, concentrated sulfuric acid. These solutions react with strongly acid solutions of copper salts to produce a com-flower-blue crystalline precipitate, whose constitution as an inner complex compound is shown in (II). 

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