Chromium compounds borate

Sodium triacetoxyborohydride, 283 Tetrabutylammonium iodide-Boron trifluoride etherate, 287 Tributylborane, 325 Tributyl borate, 326 Triethylborane, 33, 292 Trimethyl borate, 218 Zinc borohydride, 167 Chromium Compounds Arene(tricarbonyl)chromium complexes, 19... 

There is some evidence that chromium Cr " ), silicic acid (SitOH) ) or related silicon-based compounds, borate nickel and arsenate (AsO ) are... 

There is some evidence that chromium (Cr " ), silicic acid (Si(OH)4) or related silicon-based compounds, borate (8407 ), nickel (NP" ), and arsenate (AsOf ) are required inorganic nutrients. However, the available evidence tends to be not convincing to all researchers (Reeves, 1997). The functions of arsenate and nickel are not clear. There is some indication that arsenate is used in the metabolism of sulfur-containing amino acids. An experimentally induced deficiency in arsenate or nickel results in impaired growth. 

A buildup of Al + in the zinc phosphating baths will restrict the amount of coating formed unless these ions are ranoved by addition of fluoride or borate. An advantage of zinc phosphating, however, is that it avoids the use of toxic hexavalent chromium compounds. Some simple bath compositions for zinc and manganese phosphating of aluminium are... 

The obvious next step was oxidation of the tris(pyrazolyl)borate chromium alkyls to the catalytically active -t-III oxidation state. However, cyclic voltammetry experiments did not show a reversible oxidation in any case, and all attempts to prepare complexes of the type [Tp Bu,Meci-R]+X by chemical oxidation failed, yielding [Tp Cr(THF)n] X instekl. TTie reasons for the apparent instability of TpCr alkyls are not clear, and we arc continuing our efforts to isolate related compounds,... 

Four main types of antioxidants are commonly used in polypropylene stabilizer systems although many other types of chemical compounds have been suggested. These types include hindered phenolics, thiodi-propionate esters, aryl phosphites, and ultraviolet absorbers such as the hydroxybenzophenones and benzotriazoles. Other chemicals which have been reported include aromatic amines such as p-phenylenediamine, hydrocarbon borates, aminophenols, Zn and other metal dithiocarbamates, thiophosphates, and thiophosphites, mercaptals, chromium salt complexes, tin-sulfur compounds, triazoles, silicone polymers, carbon black, nickel phenolates, thiurams, oxamides, metal stearates, Cu, Zn, Cd, and Pb salts of benzimidazoles, succinic acid anhydride, and others. The polymeric phenolic phosphites described here are another type. 

Apart from the di- and oligoolefm iron tricarbonyl complexes, which nowadays are frequently used in organic synthesis [71, 72], the chemistry of the readily accessible cyclohepatriene chromium and molybdenum tricarbonyls 2 and 3 was the focus of intense research efforts as well. Only a few months after the synthesis of 2 and 3 was published [58,59], both Hyp Dauben and Peter Pauson reported that these compounds react with triphenylmethyl tetrafluoro-borate in methylene chloride to give the tropylium complexes 4 and 5 in excellent yield (Scheme 7.1) [73, 74]. Later this method of hydride abstraction was also used for the preparation of the tropylium cation itself and subsequently led to the generation of several cationic rc-complexes of iron, manganese and cobalt [71, 72], The reactions of the cations of 4 and 5 with nucleophilic... 

Historically, almost every chemical or compound known to be toxic has been tried and used to inhibit the action of wood-destroying pests. Among the many chemicals used as wood preservatives are compounds based on creosote, mercury, arsenic, thallium, borate, cyanide, chromium, copper, zinc, nickel, fluorides, and pentachlorophenol. The majority fall into 3 classes ... 

The heavier lanthanides and yttrium form a double borate RCr(B03)2 with trivalent chromium at 950-100°C. The structure of this compound is similar to dolomite (Vicat and Aleonard, 1968). At 1100-1150°C the compounds decompose to RBO3, Cr203 and B2O3. 

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