Glyoxime, dimethyl-, complexes with

In the study of effects of ultrasound on the aqueous reactions of nickel, we found some interesting results, for example, the colloidal formation of Ni-DMG complex and degassing of NH3 during different experiments. When 25 ml of 0.001 M NiSC>4 solution was complexed with 5 ml of 1% dimethyl glyoxime (DMG) in faintly alkaline ammonia medium and sonicated for 30 minutes and compared with another set of 25 ml of complexed solution which was stirred mechanically, a colloidal solution of Ni-DMG complex was formed in sonicated condition. Particles of Ni-DMG complex did not settle even after keeping 3 1 h because of their smaller size, in sonicated solution, whereas in the unsonicated condition large particles of Ni-DMG complex settled down immediately. 

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... 

Most of the separation procedures are based on the precipitation [27, 68, 72, 76, 80, 89, 99, 110, 139, 158, 170] or extraction [11, 72, 81, 119, 122, 124, 139, 162] of the Pd dimethyl-glyoxime (DMG) complex. In combination with the commonly used scavenger precipitations of Fe, La, or Zr hydroxides and Ag halides quite high decontamination factors can be achieved (see for example procedure 1 below). The samples for counting are prepared using either Pd metal or insoluble Pd compounds, like DMG complex, sulfide, or iodide. 

Nickel may he measured quantitatively hy several microanalytical gravimetric methods that include (l)formation of a red precipitate with dimethyl-glyoxime, (2) precipitation as a hlack sulfide with ammonium sulfide, (3) precipitating as a complex cyanide hy treating with alkali cyanide and bromine, and (4) precipitation as a yellow complex hy treating an ammoniacal solution of nickel with dicyandiamide sulfate (Grossman s reagent), followed hy the addition of potassium hydroxide. All of these methods can separate nickel from cobalt in solution. 

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). 

Based on a comparative study of colored iron(II) complexes of various organic nitrogen ligands, such as bipy, phen and dimethyl-glyoxime, Kozo Sone 10) associated their visible spectra with the presence of a common structural element, viz. the five membered unsaturated chelate ring III, considered as a kind of chromophore. 

The data indicate that in the concentration range investigated, the dimethyl-glyoxime and Nioxime parent complexes coordinate a single iodide ion each, while the furil dioxime parent complex is able to coordinate two iodide ions. The log values increase with an increase in the dioxane content of the solvent, i.e., with a... 

Nickel An equal amount of 10% sodium citrate solution was added to the sample. The acidity of the samples was then adjusted to pH > 7.5 by addition of NH3. Thereafter, 2 ml 1% dimethyl-glyoxime (DMG) was added to the solution. The nickel-DMG complex was extracted into pure chloroform. The extraction was repeated with fresh chloroform to improve the yield. The combined organic phases were then washed with 0.5 M NH3 to remove impurities. Nickel was then back-extracted into 0.5 ml HNO3. The back-extraction was repeated once to improve the yield. The HNO3 solution was then used for IGP-MS and liquid scintillation measurements, y-spectrometry showed no contamination that could disturb the LSC measurements. The overall yield of this standard procedure is >99%. 

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