Cadmium metal reactions with

Although it is only slowly oxidized in moist air at ambient temperature, cadmium forms a fume of brown-colored cadmium oxide [1306-19-0] CdO, when heated in air. Other elements which react readily with cadmium metal upon heating include the halogens, phosphoms, selenium, sulfur, and tellurium. The standard reduction potential for the reaction... 

An alternative method, which avoids the prior preparation of the toxic di-alkylcadmiums, is direct reaction of the perfluoroalkyl iodide with cadmium metal [729] (equation 98)... 

The trinuoromethylcadmiuni reagent can also be prepared in situ via the reaction ot dihalodifluoromethanes with cadmium metal m DMF [33] (equation 101)... 

The functionalized cadmium compound dialkoxyphosphinyldifluorometh-ylcadmium is readily prepared by direct reaction of bromodifluoromethanephos-phonates with cadmium metal [13 ] (equation 105). This cadmium reagent shows versatile chemical reactivity and reacts with a wide variety of electrophiles, as illustrated m equations 106-109 [139,140,141, 142]... 

The perfluoroallylcadmium reagent can be prepared similarly by direct reaction of perfluoroallyl iodide with cadmium metal [146] (equation 113). Reaction of this cadmium reagent with ally bromide gives F2C=CFCp2CH2CH=CH2 in 78% yield [146]. 

The perfluoroarylcadmium compounds are synthesized via reaction of indoor bromopentafluorobenzene with cadmium metal [129, 148] (equation 115) The ortho- and para-dibromotetrafluorobenzenes can give either the mono- or biscad-mium reagent depending on the reaction conditions [149] (equation 116) The mera-dibromotetrafluorobenzene gives only the monocadmium compound [149. ... 

The effect of metal-ion catalysis (especially that of cadmium ion) in the above reaction has been studied628, and in Table 201 are listed the first-order rate coefficients for protodeboronation of 2,6-dimethoxybenzeneboronic acid in malonic acid-sodium malonate buffer or perchloric acid, observed in the absence ( ) or presence ( ) of cadmium ion, together with the second-order rate coefficients (k2) obtained by dividing the difference of these values by the cadmium ion concentration. The data of the first ten rows of Table 201 are plotted in Fig. 4 and the... 

At another type of active electrode, found in many batteries, the reaction is the conversion between a metal and an Insoluble salt. At the surface of this type of electrode, metal cations combine with anions from the solution to form the salt. One example is the cadmium anode of a rechargeable nickel-cadmium battery, at whose surface cadmium metal loses electrons and forms cations. These cations combine immediately with hydroxide ions in... 

Organocadmium compounds can be prepared from Grignard reagents or organo-lithium compounds by reaction with Cd(II) salts.180 They can also be prepared directly from alkyl, benzyl, and aryl halides by reaction with highly reactive cadmium metal generated by reduction of Cd(II) salts.181... 

Efforts to improve the efficient synthesis of organocadmium complexes by reaction of elemental cadmium with alkyl halides have been reported. Recent studies show that the presence of catalytic amounts of Cul and BuMgl in the reaction of alkyliodides with cadmium metal allows for the formation of 172a-c in high yield and high purity (Equation (58)).241... 

Metallothioneins (MT) are unique 7-kDa proteins containing 20 cysteine molecules bounded to seven zinc atoms, which form two clusters with bridging or terminal cysteine thiolates. A main function of MT is to serve as a source for the distribution of zinc in cells, and this function is connected with the MT redox activity, which is responsible for the regulation of binding and release of zinc. It has been shown that the release of zinc is stimulated by MT oxidation in the reaction with glutathione disulfide or other biological disulfides [334]. MT redox properties led to a suggestion that MT may possesses antioxidant activity. The mechanism of MT antioxidant activity is of a special interest in connection with the possible antioxidant effects of zinc. (Zinc can be substituted in MT by some other metals such as copper or cadmium, but Ca MT and Cu MT exhibit manly prooxidant activity.)... 

Cadmium fluoride is prepared by the reaction of gaseous fluorine or hydrogen fluoride with cadmium metal or its salt, such as chloride, oxide or sulfide ... 

Reaction with amorphous silicon at 900°C, catalyzed by steam produces cadmium orthosilicate, Cd2Si04. The same product also is obtained by reaction with sdica. Finely divided oxide reacts with dimethyl sulfate forming cadmium sulfate. Cadmium oxide, upon rapid heating with oxides of many other metals, such as iron, molybdenum, tungsten, titanium, tantalum, niobium, antimony, and arsenic, forms mixed oxides. For example, rapid heating with ferric oxide at 750°C produces cadmium ferrite, CdFe204 ... 

Sulphides. Acquaint yourself with the solubility products of zinc and cadmium sulphides (see Appendix 1, Table 12). Prepare the sulphides of these metals from solutions of zinc and cadmium nitrates. What should be used as the precipitant—hydrogen sulphide or ammonium sulphide Note the colour of the precipitates and test their reaction with 1 N solutions of sulphuric and hydrochloric acids. 

Reactions with metals. When mercury fulminate is boiled with water containing metallic suspensions, the majority of metals (e.g. aluminium, zinc, copper), form their fulminates and mercury is precipitated. Reaction can also occur at room temperature, except with nickel. Other metals may be ranged according to increasing reactivity silver, tin, bismuth, cadmium, iron, lead, copper, zinc, brass, aluminium. With aluminium, the reaction takes only a few hours, yielding a large amount of A1203. 

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