Amalgams alcohols

Aluminum amalgam Alcohols from oxido compds. Selective reduction... 

Usually prepared by the action of NaCN on benzaldehyde in dilute alcohol. It is oxidized by nitric acid to benzil, and reduced by sodium amalgam to hydrobenzoin PhCHOHCHOHPh by tin amalgam and hydrochloric acid to des-oxybenzoin, PhCH2COPh and by zinc amalgam to stilbene PhCH = CHPh. It gives an oxime, phenylhydrazone and ethanoyl derivative. The a-oxime is used under the name cupron for the estimation of copper and molybdenum. 

Colourless crystals m.p. 122 C. It is prepared by reducing an alcoholic solution of xanthone with sodium amalgam. 

Aliphatic hydrocarbons can be prepared by the reduction of the readily accessible ketones with amalgamated zinc and concentrated hydrochloric acid (Clemmensen method of reduction). This procedure is particularly valuable for the prep>aration of hydrocarbons wdth an odd number of carbon atoms where the Wurtz reaction cannot be applied with the higher hydrocarbons some secondary alcohol is produced, which must be removed by repeated distillation from sodium. 

Acetone is reduced by amalgamated magnesium largely to a bimolecu lar reduction product, tetramethylethylene glycol or plnacol (CHjjjClOHjClOHjiCHj), some isopropyl alcohol is also formed ... 

Pinacol possesses the unusual property of forming a crystalline hexahydrate, m.p. 45°, and the pinacol is separated in this form from the unreacted acetone and the tsopropyl alcohol. The magnciaium is conveniently amalgamated by dissolving mercuric chloride in a portion of the acetone mercury is then liberated by the reaction ... 

Clemmensen reduction of aldehydes and ketones. Upon reducing aldehydes or ketones with amalgamated zinc and concentrated hydrochloric acid, the main products are the hydrocarbons (>C=0 —> >CHj), but variable quantities of the secondary alcohols (in the case of ketones) and unsaturated substances are also formed. Examples are ... 

The aluminium amalgam is prepared as described in Section 11,50,72. After washing with water, it slioidd lir.st be washed with methyl alcohol and Anally with a little dry benzene. 

Hydrocinnamic acid may also be prepared by the reduction of cinnamic acid with sodium and alcohol or with sodium amalgam or with hydrogen in the presence of Adams platinum oxide catalyst (Section 111,150) ... 

Xanthhydrol. Prepare an amalgam from 9 0 g. of clean sodium and 750 g. (55 ml.) of mercury (Section 11,50,7, Method 1), and warm it to 50° in a 500 ml. Pyrex bottle. Add a cold suspension of 25 g. of xanthone in 175 ml. of rectified spirit, stopper the bottle and shake vigorously raise the stopper from time to time to release the pressure. The temperature rises rapidly to 60-70°, the sohd xanthone passes into solution, and a transient blue colour is developed. After about 5 minutes the alcoholic solution is clear and almost colourless. Shake for a further 10 minutes, separate the mercury, and wash it with 15 ml. of alcohol. Filter the... 

So, how does this whole thing work It s as simple as it sounds. An alcoholic solution of nitromethane and MDP2P is dripped into a mass of amalgamated aluminum immersed in alcohol first reducing the nitromethane to methylamine, allowing the Schiff base of the amine and ketone to form which is then further reduced to the desired MDMA. 

Two methods for converting carbonyl groups to methylene units are the Clem mensen reduction (zinc amalgam and con centrated hydrochloric acid) and the Wolff-Kishner reduction (heat with hydra zine and potassium hydroxide in a high boiling alcohol)... 

Metal acetylides Metal-air cells Metal alcoholates Metal alkoxides Metal alloys Metal amalgams... 

Cyclic Peroxides. CycHc diperoxides (4) and triperoxides (5) are soHds and the low molecular weight compounds are shock-sensitive and explosive (151). The melting points of some characteristic compounds of this type are given in Table 5. They can be reduced to carbonyl compounds and alcohols with zinc and alkaH, zinc and acetic acid, aluminum amalgam, Grignard reagents, and warm acidified iodides (44,122). They are more difficult to analyze by titration with acidified iodides than the acycHc peroxides and have been sucessfuUy analyzed by gas chromatography (112). 

The speed of the reaction depends both on the metal and on the alcohol, increasing as electropositivity iacreases and decreasiag with length and branching of the chain. Thus sodium reacts strongly with ethanol, but slowly with tertiary butyl alcohol. The reaction with alkaU metals is sometimes carried out ia ether, ben2ene, or xylene. Some processes use the metal amalgam or hydride iastead of the free metal. Alkaline earth metals and aluminum are often covered with an oxide film which hinders the reaction. 

Manufacture is either by reaction of molten sodium with methyl alcohol or by the reaction of methyl alcohol with sodium amalgam obtained from the electrolysis of brine in a Castner mercury cell (78). Both these methods produce a solution of sodium methylate in methanol and the product is offered in two forms a 30% solution in methanol, and a soHd, which is a dry, free-flowing white powder obtained by evaporating the methanol. The direct production of dry sodium methylate has been carried out by the introduction of methanol vapors to molten sodium in a heavy duty agitating reactor. The sohd is supphed in polyethylene bags contained in airtight dmms filled in a nitrogen atmosphere. 

Reduction of vanillin by means of platinum black in the presence of ferric chloride gives vanillin alcohol in excellent yields. In 1875, Tiemann reported the reduction of vanillin to vanillin alcohol by using sodium amalgam in water. The yields were poor, however, and there were a number of by-products. High yields of vanillin alcohol have been obtained by electrolytic reduction. 

Sodium ethoxide can also be prepared by the reaction of sodium amalgam with ethyl alcohol. 

Heptyl alcohol has been prepared by the reduction of heptaldehyde with zinc dust and acetic acid,i with sodium amalgam and acetic acid, with sodium in toluene and acetic acid, and with hydrogen and a platinum catalyst. Heptaldehyde has also been reduced biochemically by adding it to a fermenting sugar solution. Heptyl alcohol has been prepared by the reduction of heptoamide with sodium and amyl alcohol. ... 

M-Hexyl alcohol has been prepared by the reduction of ethyl caproate by means of sodium and absolute alcohoB alone or in anhydrous ammonia solution by the reduction of -caproamide by means of sodium and absolute alcohol by the reduction of -caproaldehyde by means of sodium amalgam in dilute sulfuric acid and by means of living yeast, It has also been produced by the action of nitrous acid upon w-hexylamine by the action of sodium upon a mixture of ethyl alcohol and M-butyl alcohol ... 

Aluminium amalgam. Mainly used for removing traces of water from alcohols via refluxing followed by distillation. 

The present procedure was developed from those of Wallach and Freylon, based upon the general method discovered by Leuckart. a-Phenylethylamine also can be prepared satisfactorily by the reduction of acetophenone oxime with sodium and absolute alcohol or sodium amalgam, but the reagents are more expensive and the processes less convenient. The amine has been obtained by reducing acetophenone oxime electro-lytically, by reducing acetophenone phenylhydrazone with sodium amalgam and acetic acid, from a-phenylethyl bromide and hexamethylenetetramine, and by the action of methyl-magnesium iodide upon hydrobenzamide, as well as by other methods of no preparative value. 

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