Cadmium complexes ethers

Electrochemical oxidation of cadmium in a solution of ](4-methylphenyl)sulfonyl]-2-pyridylamine] (HL) in acetonitrile/di chloromethane mixtures resulted in CdL2 complex formation [149]. The electrochemical oxidation of cadmium amalgam in nonaqueous solvents CH2CI2, 1,2-C2H4CI2, and PC was also used for the preparation of cadmium complexes with 18-membered macromonocyclic ligands, 18-06, 18-S6, I8-N2O4, and 18-N6 [150]. The stoichiometry and stability of resulted complexes were determined. The same method was used to examine the complexation of Cd(II) cation with 12-crown-4 ether, azacrown ether 1,4,8,11-tetra-azacyclotetradecane, and thiaazacrown... 

Prepare a solution of 2.72 g cadmium bromide and dissolve in this solution 2.38 g KBr and heat to dissolve the solids. Prepare a solution 2.42 g copper(lI) nitrate trihydrate to which 1.2 g diaminoethane has been added and heat the solution. Add the hot solution slowly and, with constant stirring, to the hot cadmium complex solution. Allow to cool and filter the dark violet crystals under suction. Wash on the filter with water to remove any unreacted compounds then with small volumes of alcohol and ether. Dry by continued suction while pressing between filter paper. 

Crown ethers [364] have proved to be an excellent choice as ionophores for the fabrication of ion sensors because of their ability to complex selectively a particular ion. The cadmium selective sensors have been fabricated from poly(vinyl chloride) (PVC) matrix membranes containing macrocyclic ionophores benzo-15-crown-5 [365], monoaza-18-crown-6 [366], dibenzo-24-crown-8 [367], dicyclohexano-18-crown-6 [368], 3,4 ll,12-dibenzo-l,6,... 

At low temperatures in inert solvents (such as methylene dichloride) a controlled polymerization can be effected using various acids and alkylating agents. These initiators include boron trifluoride etherate, triethylaluminum, trityl hexachloroantimonate, triethylam-monium hexachloroantimonate, diethyloxonium hexafluoroantimonate, p-toluenesulfonic acid and diethylzinc or cadmium-1,2-dioI complexes. Crystalline, high molecular weight... 

In his early work Pedersen investigated crown ether complexation by UV spectroscopy. He reported that complexation caused a shift in the absorption maximum of dibenzo[18]crown-6 of about 6 nm to a longer wavelength (B-78MI52101). The test was not totally reliable as cadmium caused no change in the spectrum yet gave a crystalline complex. In general, however, UV-visible spectroscopy is of limited use in the study of macrocyclic complexes. 

The 1 2 complex of tetraethyleneglycol dimethyl ether with cadmium chloride has been shown to be a tetramer.690... 

Bis[trifluoromethyl] tellurium and bis[pentafluorophenyl] tellurium react with dimethyl zinc or dimethyl cadmium with stepwise replacement of the perfluoroorganyl groups by methyl groups2,3. These reactions were carried out in trichlorofluoromethane in the presence of bis[2-ethoxyethyl] ether as the complexing agent for the perfluoroorgano element compounds2. 

These two complex hydrides have been used also in inorganic syntheses. Lithium aluminum hydride may be used to prepare unstable hydrides in ether at low temperatures from the appropriate halides cadmium hydride and mercury hydride (Chap. 2) have been so prepared. A number of additional borohydrides, aluminum hydrides, and even a gallohydride (LiGaH4) have been reported. 

The first cell localization study, involving mononuclear cells, was carried out as a complement to the anti-viral photodynamic work. Here, the basic motivation for the study derived from the realization that HIV-1 replicates in human T-4 lymphocytes and that, as such, selective light-derived inactivation of such cells would be of benefit in possible photodynamic blood purification processes (see Sect. 12). Texaphyrin proved to be quite effective in the photodestruction of mononuclear cells. In fact it was found that the cadmium texaphyrin complex 116 is as effective on a per mole basis as the dihematoporphyrin ether (DHE) and slightly more so on a per photon basis. 

Zinc-modified cyanoborohydride, prepared from anhydrous zinc chloride and sodium cyanoborohy-dride in the ratio 1 2 in ether, selectively reduced aldehydes and ketones but not acids, anhydrides, esters and tertiary amides. In methanol the reactivity paralleled the unmodified reagent. Zinc and cadmium borohydrides form solid complexes with DMF, which may prove to be convenient sources of the reducing agents.Aromatic and a,p-unsaturated ketones were reduced much more slowly than saturated ketones, so chemoselective reduction should be possible. 

The colorless zinc compound, Zn(CisH6)2, which sublimes at 160° under partial decomposition, is obtained in small yield from zinc chloride and cyclopentadienyl sodium in diethyl ether however, the less stable cadmium compound decomposes, with separation of cadmium, under these conditions (55). The mercury compound, Hg(CsH5)2, is produced in 20% yield by the action of the sodium derivative on mercuric chloride in tetrahydrofuran (215). The action of cyclopentadiene on the complex K2(HgI ) in aqueous alkaline solution results in the precipitation of a mixture of CsHsHgl and Hg(CsH6)2, from which the latter compound may be obtained in good yield by extraction with a mixture of tetrahydrofuran and petroleum ether (62). It forms pale yellow crystals which begin to decompose at about 60° and which melt at 83-85°. The compound is readily soluble in most solvents it decomposes slowly even when kept in the dark at room temperature it is insoluble in water and reacts with neither water nor bases. On the other hand, decomposition occurs in dilute hydrochloric acid. It converts ferric chloride to ferrocene quantitatively, and it yields an adduct with maleic anhydride (215). 

The complexes of urea and thiourea with boron trifluoride have been studied and, as with other boron trifluoride complexes, the shifts are very similar namely 19 2+0-3 p.p.m. [with respect to (MeO)aB]. A similar shift was observed for the more complex adducts with cadmium chloride or nickel bromide. It was found that dimethyl ether-boron trifluoride (shift of 17-6) and di-t-butylthiourea-boron... 

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