Metal glyoximates

Table 3 Non-integral Oxidation State Metal Glyoximates and Benzoquinone Dioximates...

Table 8. Structures of metal glyoximates in integral and non-integral oxidation states3... 

RETENTION OF DIFFERENT CLASSES OF ORGANIC COMPOUND ON METAL GLYOXIMES RELATIVE TO SQUALANE 187)... 

Replacement of the hydrogen bonds in oxime complexes with boron bridges leads to macrocyclic complexes such as those from dimethyl glyoxime (equation 59).201,202 This kinetic template technique has been used for the encapsulation of metals inside cage ligands.203 204... 

Conducting halogenated linear metal atom chain systems were first reported in 195095 and are now known for Ni and/or Pd complexes of glyoxime (GLY), DPG and BQD. The compounds are usually produced by treating a hot solution of the neutral complex in o-C6H4C12 with I2 and lustrous coloured crystals of the NIOS compound are obtained on cooling the solution. The limited range of compounds studied is shown in Table 3 and all have metal-over-metal stacked structures. 

The precipitate consists of palla- Reduce the solution dium dimethyl glyoxime. Ignite with zinc and hydro-to yield metallic Palladium. chloric acid. 

Note 2. The gold thrown out of solution by the dimethyl glyoxime is usually contaminated with traces of platinum. The whole is dissolved in aqua regia and the platinum precipitated in the usual way with ammonium ohloride. The gold is then precipitated in the metallic condition with ammonium oxalate. 

CA 45, 6541 (1951) [(Formation of NsoGu salts and their analytical evaluation). (The Ag, Cu, and Ni salts were prepd in hopes of their being useful for analysis of these metals as the system is very similar to glyoxime the results were not favorable. The... 

The synthesis of mono- and trisubstituted ribbed-functionalized d-metal tris-dioximates starting from the initial monohalogen-dioximes can be realized by Scheme 128. An alternative pathway of halogenation of the monosubstituted glyoxime derivatives is complicated because of side reactions of the clathrochelate framework destruction and halogenation of the substituents in a-dioximate fragments and at the boron atom, as well as by the fact that the products of partial halogenation (in the case of trisubstituted clathrochelates) may predominate. 

Halogen oxidation of planar complexes, particularly of the nickel triads that contain bidentate glyoximes or macrocyclic ligands, such as, phthalocyanines, substituted porphyrins, or tetraazaannulenes, leads to highly conducting substances that may possess chains of metal atoms as well as chains of polyhalides ... 

Ni(ii) forming 4 coplanar bonds. Planar diamagnetic complexes include the Ni(CN)4 ion, which has been studied in the and other salts (Ni-C, 1-85 A), and molecules such as (a) and (b). The numerous complexes with bidentate ligands include the thio-oxalate ion, (c), molecules of the types (d) ) and (e), and the glyoximes, (0> notable for the short intramolecular hydrogen bonds. Many divalent metals form phthalocyanins, M(ii) replacing 2 H in C32H18N8 (Fig. 27.9). 

Figure 4.13 Molecular structures of macrocyclic metal complexes metal bis(glyoximate), metal tetraazaanulene and metal phthalocyanine complexes...

Nickel is determined by the gravimetric dimethyl-glyoxime procedure after reduction of the compound with sulfur dioxide and hydrochloric acid. Iodine is determined as silver iodide after reduction with sulfur dioxide in sulfuric acid medium. Total active oxygen is calculated by measuring the quantity of iodine liberated from potassium iodide in acidic solution. Alkali metals are determined as sulfates in the filtrates from the nickel determinations. 

Among the more widely studied 2,3-C-disubstituted ligands related to ethylenediamine are sbn and stien (Table 3). These ligands can exist in meso and racemo forms and the properties e.g. solubility) of transition metal complexes (especially Co" ) with the two forms of this type of ligand are often sufficiently different as to allow amine isomer separation to be achieved without separation of the amine mixture. Meso and racemic 5bn are prepared together by the reduction of dimethyl-glyoxime and can be separated by fractional crystallization of the dihydrochloride salts. There are, however, stereospecific synthetic routes available for the meso and racemo forms of stien (Table 6). 

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