Amalgam, aluminum potassium

The aluminum derivative of ethyl acetoacetate has been prepared by the reaction of aluminum ethoxide with ethyl acetoacetate, by the reaction of amalgamated aluminum metal with ethyl acetoacetate, and by the reaction of potassium aluminate with ethyl acetoacetate. The present synthesis is a modification of the first method. 

The first person to accomplish that task was Danish chemist and physicist Hans Christian Oersted (1777-1851). Oersted heated a combination of alumina and potassium amalgam. An amalgam is an alloy of a metal and mercury. In this reaction. Oersted produced an aluminum amalgam—aluminum metal in combination with mercury. He was unable, however, to separate the aluminum from the mercury. 

Compared with copper, iron, gold, and lead, which were known in antiquity, aluminum is a relative newcomer. Sir Humphry Davy obtained it as an alloy of iron and proved its metallic nature in 1809. It was first prepared in relatively pure form in 1825 by H. C. Oersted through reduction of aluminum chloride with an amalgam of potassium dissolved in mercury,... 

Strontium [7440-24-6] Sr, is in Group 2 (IIA) of the Periodic Table, between calcium and barium. These three elements are called alkaline-earth metals because the chemical properties of the oxides fall between the hydroxides of alkaU metals, ie, sodium and potassium, and the oxides of earth metals, ie, magnesium, aluminum, and iron. Strontium was identified in the 1790s (1). The metal was first produced in 1808 in the form of a mercury amalgam. A few grams of the metal was produced in 1860—1861 by electrolysis of strontium chloride [10476-85-4]. 

The reduction of iminium salts can be achieved by a variety of methods. Some of the methods have been studied primarily on quaternary salts of aromatic bases, but the results can be extrapolated to simple iminium salts in most cases. The reagents available for reduction of iminium salts are sodium amalgam (52), sodium hydrosulfite (5i), potassium borohydride (54,55), sodium borohydride (56,57), lithium aluminum hydride (5 ), formic acid (59-63), H, and platinum oxide (47). The scope and mechanism of reduction of nitrogen heterocycles with complex metal hydrides has been recently reviewed (5,64), and will be presented here only briefly. 

In 1825, however, he studied the chemical action of the voltaic current, and tried to isolate chemically the metal believed to be present m alumina. He first prepared liquid aluminum chloride by passing a current of chlorine gas over a mixture of charcoal and alumina heated to redness. By allowing potassium amalgam to react with the aluminum chloride, he prepared an aluminum amalgam, and by distilling off the mercury out of contact with the air, he obtained a metal that looked like tin (11). 

The compound of chlorine with the combustible element of the clay (aluminum chloride) is volatile at a temperature which is not much above that of boiling water, it is somewhat yellowish, perhaps however from admixed carbon it is soft, but still has crystalline form, it absorbs water with avidity and dissolves therein with great ease and with evolution of heat. Rapidly heated with potassium amalgam, it is decomposed, potassium chloride and aluminum amalgam being formed. This amalgam is very quickly decomposed in contact with the atmosphere By distillation without contact with the... 

Oersted s product must have been impure, metallic aluminum containing mercury, but when Wohler repeated the experiment he found that the gray molten mass formed by die action of the potassium amalgam on the aluminum chloride volatilized completely when heated (12, 46). Kirstine Meyer s careful study of Oersted s unpublished notes and I. Fogh s and M. Tosterud and J. D. Edwards repetitions of his experiment show that the great Danish physicist allowed a dilute amalgam containing about 1.5 per cent of potassium to react with excess aluminum chloride, and that it is possible to prepare the metal in this manner (42, 44, 45, 53). 

Although aluminum was predicted by Lavoisier (France) as early as 1782, when he was investigating the properties of aluminum oxide (alumina), the metal was not isolated until 1825 by H.C. Oersted (Denmark). Oersted obtained an impure aluminum metal by heating potassium amalgam with anhydrous aluminum chloride, followed by... 

REDUCTION, REAGENTS Aluminum amalgam. Borane-Dimethyl sulfide. Borane-Tetrahydrofurane. t-Butylaminoborane. /-Butyl-9-borabicyclo[3.3.1]nonane. Cobalt boride— f-Butylamineborane. Diisobutylaluminum hydride. Diisopropylamine-Borane. Diphenylamine-Borane. Diphenyltin dihydride. NB-Enantrane. NB-Enantride. Erbium chloride. Hydrazine, lodotrimethylsilane. Lithium-Ammonia. Lithium aluminum hydride. Lithium borohydride. Lithium bronze. Lithium n-butylborohydride. Lithium 9,9-di-n-butyl-9-borabicyclo[3.3.11nonate. Lithium diisobutyl-f-butylaluminum hydride. Lithium tris[(3-ethyl-3pentylK>xy)aluminum hydride. Nickel-Graphite. Potassium tri-sec-butylborohydride. Samarium(II) iodide. Sodium-Ammonia. Sodium bis(2-mcthoxyethoxy)aluminum hydride. 

Aluminum is a metal that came of age in the twentieth century. Its volume of production has grown from about 1/lOOth that of copper, lead, and zinc prior to 1900, to two to four times the volume of these more common nonferrous metals during the last century (Table 12.1). H.C. Oersted, in 1825 (Table 12.1) in Denmark, was the first to isolate aluminum in impure form by the reduction of aluminum chloride with potassium amalgam. Two years later in Germany, F. Wohler obtained higher purity metal and fully described its properties. H.E. St.-Claire Deville put aluminum production into commercial practice in France by 1845 using sodium fusion to reduce aluminum chloride (Eq. 12.1). 

Advances in alumina reduction technology have been surveyed [17], and alternative pathways to aluminum examined [18]. Aluminum can be obtained by metallic, carbon, or electrolytic reduction of appropriate compounds. The earliest processes successfully used metallic reduction via potassium amalgam or sodium fusion to produce aluminum from aluminum chloride (Eqs. 12.21 and 12.22). 

Alumina-Potassium hydroxide ( Basic alumina ) [1. 20. before Aluminum amalgam],... 

MERCURIO (Italian, Spanish) (7439-97-6) Violent reaction with alkali metals, aluminum, acetylenic compounds, azides, boron phosphodiiodide (vapor explodes), bromine, 3-bromopropyne, chlorine, chlorine dioxide, ethylene oxide, lithium, metals, methyl silane (when shaken in air), nitromethane, peroxyformic acid, potassium, propargyl bromide, rubidium, sodium, sodium carbide. Forms sensitive explosive products with acetylene, ammonia (anhydrous), chlorine, picric acid. Increases the explosive sensitivity of methyl azide. Mixtures with hot sulfuric acid can be explosive. Incompatible with calcium, sodium acetylide, nitric acid. Reacts with copper, silver, and many other metals (except iron), forming amalgams. 

Wohler s other major achievement was his isolation of the element aluminum in 1827. Attempts by chemists Humphry Davy and Berzefius to prepare aluminum from alumina (AI2O3) via electrolytic decomposition had all failed. Wohler employed a chemical approach that included the reduction of anhydrous aluminum chloride by potassium amalgam, followed by treatment with water. It produced a gray powder that Wohler was able to identify as the element aluminum. 

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