Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Mercuric chloride aluminum

Acetic acid, fp 16.635°C ((1), bp 117.87°C at 101.3 kPa (2), is a clear, colorless Hquid. Water is the chief impurity in acetic acid although other materials such as acetaldehyde, acetic anhydride, formic acid, biacetyl, methyl acetate, ethyl acetoacetate, iron, and mercury are also sometimes found. Water significantly lowers the freezing point of glacial acetic acid as do acetic anhydride and methyl acetate (3). The presence of acetaldehyde [75-07-0] or formic acid [64-18-6] is commonly revealed by permanganate tests biacetyl [431-03-8] and iron are indicated by color. Ethyl acetoacetate [141-97-9] may cause slight color in acetic acid and is often mistaken for formic acid because it reduces mercuric chloride to calomel. Traces of mercury provoke catastrophic corrosion of aluminum metal, often employed in shipping the acid. [Pg.64]

Catalytic amounts of mercuric chloride are usually employed in this preparation. Aluminum isopropoxide is a useful Meerwein-Potmdorf-Verley reducing agent in certain ester-exchange reactions and is a precursor for aluminum glycinate, a buffering agent (see Alkoxides, metal). [Pg.105]

WeU-cleaned aluminum filings react at room temperature in the presence of mercuric chloride (20,21). In an autoclave, metallic aluminum and ethyl alcohol react without a catalyst at 120°C (22). The reaction can also be promoted by the addition of sodium ethoxide (23). Aluminum should be avoided as a material of constmction for ethanol service. [Pg.402]

A rather special procedure for the preparation of 21-hydroxy-20-ketopreg-nanes starts with the 17a-ethoxyethynyl-17 -hydroxy steroids described earlier. Free radical addition of ethanethiol to the triple bond, followed by acid-catalyzed hydrolysis and dehydration gives the 20-thioenol ether 21-aldehyde. This can be reduced with lithium aluminum hydride to the C-21 alcohol and then hydrolyzed to the C-20 ketone in the presence of mercuric chloride. The overall yield, without isolation of intermediates, is in the order of 50% ... [Pg.212]

Reduction of the enamine system of an aminostilbene by sodium in liquid ammonia 189) and of a 17-enaminosteroid by aluminum and mercuric chloride in alcohol 560) have also been reported. [Pg.433]

The second method, published later that year, represents probably the best laboratory preparation of Cp2Ti(CO)2 (1) to date (27). It involved the reduction of Cp2TiCl2 by means of aluminum filings activated with mercuric chloride. This reaction occurs via the green (Cp2TiCl)2 complex... [Pg.323]

To obtain an N-substituted amine reflux 0.1M ketone, 17 g aluminum filings or foil, 50 ml ethanol, 40 ml 30% aqueous n-butylamine (or other amine), and 0.5 g of mercuric chloride for 3 hours. Cool and pour on 500 g crushed ice and 200 ml 10% KOH. Extract 3 times with ether and dry, evaporate in vacuum (or wash combined ether layers 2 times with 10% HCI, basify acid extract with 15% NaOH and extract 3 times with ether and dry, evaporate in vacuum) to get the n-butyl-amine (or other amine). [Pg.106]

Aluminum Amalgam. Immerse thin strips of aluminum foil in a two percent aqueous solution of mercuric chloride for 30-60 seconds. Use a big bowl and plenty of solution for a moderate amount of foil. Decant off the solution, rinse the foil strips with dry ethanol, ether, and cut them into pieces of about Icm. ... [Pg.32]

Reductions with aluminum are carried out almost exclusively with aluminum amalgam. This is prepared by immersing strips of a thin aluminum foil in a 2% aqueous solution of mercuric chloride for 15-60 seconds, decanting the solution, rinsing the strips with absolute ethanol, then with ether, and cutting them with scissors into pieces of approximately 1 cm [141,142]. In aqueous and non-polar solvents aluminum amalgam reduces cumulative double bonds [143], ketones to pinacols [144], halogen compounds [145], nitro compounds [146, 147], azo compounds [148], azides [149], oximes [150] and quinones [151], and cleaves sulfones [141, 152, 153] and phenylhydrazones [154] (Procedure 30, p. 212). [Pg.27]

In a one-liter flask fitted with a reflux condenser 31.8 g (0.265 mol) of acetophenone is dissolved in 130 ml of absolute ethanol and 130 ml of dry sulfur-free benzene, and 0.5 g of mercuric chloride and 8 g (0.296 g-atom) of aluminum foil are added. Heating of the mixture initiates a vigorous reaction which is allowed to proceed without external heating until it moderates. Then the flask is heated to maintain reflux until all of the aluminum has dissolved (2 hours). After cooling the reaction mixture is treated with dilute hydrochloric acid and the product is extracted with benzene. The combined organic layers are washed with dilute acid, with a solution of sodium carbonate, and with a saturated solution of sodium chloride they are then dried with sodium sulfate and the solvent is evaporated under reduced pressure. A rapid vacuum distillation affords a fraction at 160-170° at 0.5 mm which, after dissolving in petroleum ether (b.p. 65-110°), gives 18.0 g (56%) of 2,3-diphenyl-2,3-butanediol, m.p. 100-123°. [Pg.212]

This reaction was applied to the synthesis of quinonoid natural products [34]. Propargyl bromides 62 a and 62b, which were prepared from prenyl bromide and phytyl bromide by a standard procedure, were converted to the corresponding aluminum reagents by reaction with powdered aluminum and a catalytic amount of mercuric chloride [35]. Then the iodomagnesium salt of cyclopropanol hemiacetal was treated with these reagents [36] affording the prenyl derivative 63 a and the phytyl derivative 63 b in 49 and 50% yield, respectively (Scheme 26). [Pg.86]

Diethyl ether, Dichloromethylphosphine, Ethyl alcohol, N,N-Diethylamine, 2-Dimethylaminomethanol, Rhombic sulfur Acetylene, Arsenic trichloride. Aluminum chloride Acetylene, Arsenic trichloride. Mercuric chloride, Hydrochloric acid Methylene chloride. Magnesium metal turnings, Tetrahydrofuran, Arsenic trichloride, Hexanes... [Pg.156]

A standard solution of B-5 fixative containing a concentration of mercuric chloride of 60 g/1 was plated for 8 hours and yielded 60% recovered mercury metal. Two liters of solution were plated, thus a total of 120 g of mercuric chloride were processed. The stoichiometric amount of mercury metal from the reduction of 120 g of mercuric chloride equals 88 g. The recovered mercury metal totaled 53 g, thus demonstrating a 60% recovery efficiency. During the eight hour process the aluminum cathodes were changed once. The solution pH was between 3.6-3.8. 10 g of calcium chloride were added in order to... [Pg.300]

The use of larger amounts of mercuric chloride increases the difficulty of getting the final product free from color. This difficulty may be avoided by previously amalgamating the aluminum.3, 4 The mixture is shaken to distribute the mercuric chloride and thus aid in an even amalgamation of the aluminum. [Pg.9]

Aluminum fer/.-butoxide can be prepared by refluxing dry tert. -butyl alcohol with amalgamated aluminum 5l 6 or aluminum plus mercuric chloride.6 The method described is that of Adkins and Cox.0 The preparation of amalgamated aluminum has been described.3, 4 Aluminum isopropoxide can be prepared from dry isopropyl alcohol and aluminum,1 2 the method being essentially that described for aluminum ethoxide (Org. Syn. is, 82). [Pg.10]

ELECTRODE. Either ul two substances having different electromotive activity that enables an electric current to flow in the presence of an electrolyte. See also Electrolyte. Electrodes are sometimes called plates or terminal. Commercial electrodes are made uf a number of materials that vary widely in electrical conductivity, i.e.. lead, lead dioxide, zinc, aluminum, copper, iron, manganese dioxide, nickel, cadmium, mercury, titanium, and graphite research electrodes may be calomel mercurous chloride), platinum, glass or hydrogen. [Pg.543]

SYNTHESIS A solution of 0.12 g mercuric chloride in 180 mL H20 was added to 5 g aluminum foil that had been cut into 1 inch squares, and amalgamation allowed to proceed for0.5 h. The gray cloudy aqueous phase was decanted, and the resulting... [Pg.164]

The choice of acid to be used depends on the sample. Relatively soluble inorganic samples, salts, active metals, or alloys may be dissolved in water or dilute acid. Electropositive metals will also dissolve in dilute acid, although aluminum may need a trace of mercuric chloride added to prevent the formation of an impervious oxide layer. [Pg.232]

In both of the above cases the aluminum isopropoxide was prepared from aluminum metal amalgamated with a small amount of mercuric chloride, and was used without purification. Such an unpurified solution has been used successfully in many instances and excellent yields of the alcohol have been obtained. However, in these special cases in which the alcohols are sensitive to dehydration it is preferable to use distilled aluminum isopropoxide inconsistent yields and an impure product were obtained when 4 -ketotetrahydro-3,4-benzpyrene (XXXIII) was reduced with unpurified reagent, but with distilled reagent the yield of the alcohol was always in the range 79-90%.31... [Pg.189]

Twenty-seven grams (1 mole) of aluminum wire or foil which has just been cleaned with emery paper and wiped with a clean cloth (if turnings are employed, it may be necessary to dean, amalgamate, and dry them according to the procedure of Wislicenus)64 66 is placed in a 1-1. round-bottomed flask containing 300 cc. of anhydrous isopropyl alcohol (distilled from calcjum oxide) and 0.5 g. of mercuric chloride. The flask is attached to an efficient reflux condenser, which is protected from moisture by a mercury trap or a calcium chloride drying tube, and the mixture is heated on the steam bath or a hot plate. When the liquid is boiling, 2 cc. of carbon tetrachloride, which is an effective catalyst for the... [Pg.198]

For many purposes it is not necessary to distil the reagent the dark solution which results after all the aluminum has reacted is used directly. In this case it is usually best to prepare just the amount needed for the reduction. The proportions of 1 g. of aluminum, 0.05 g. of mercuric chloride, 20 cc. of isopropyl alcohol, and 0.2 cc. of carbon tetrachloride... [Pg.199]

A related reaction which leads to the direct introduction of an acyl group into the pyridine nucleus involves the reaction of benzoate esters or dimethyl amides with pyridine in the presence of magnesium or aluminum and mercury and mercuric chloride.308 When aluminum is used in the reaction of ethyl benzoate with pyridine, 2-benzoyl-(23.9%) and 4-benzoylpyridine (6.4%) are obtained. Under these... [Pg.302]

In a flask fitted with a reflux condenser is placed 27 parts of aluminum filings or groats. This is treated with 276 parts of absolute alcohol and 0.1 to 0.25 part of mercuric chloride and several crystals of iodine. After a few minutes a violent evolution of hydrogen takes place, and by heating on the water bath for several hours the ethylate is produced in the form of a grayish powder. [Pg.82]

The aldehyde is also obtained by the hydroformylation of allylbenzene.6 An alternative method involves benzylation of 2-ethylthiazoline followed by reduction with aluminum amalgam and cleavage with mercuric chloride.( A sixth method of preparation is the phenylation of 2-vinyl-5,6-... [Pg.131]

Preparation of secondary (or tertiary) carbinols from pyridines and an aldehyde (or a ketone) in the presence of magnesium or aluminum and mercuric chloride is known in pyridine chemistry as the Emmert reaction. 7 70 For example, dimethyl-2-pyridylcarbinol is obtained in this way from pyridine and acetone. When a mixture of pyridine and acetone is subjected to an electrolytic reduction in dilute sulfuric acid at lead electrodes, a mixture of two main products results, namely, 2-(2-hydroxy-2-propyl)-3-piperideine and 4-(2-hydroxy-2-propyl)piperidine. Analogous compounds are obtained with the use of methyl ethyl ketone as the reactant. The mixed electrolytic reduction of 2-methylpyridine and acetone affords 2-(2-hydroxy-2-propyl)-6-methyl-3-piper ideine (74) and 2-methyl-4-(2-hydroxy-2-propyl)-piperidine.71... [Pg.67]


See other pages where Mercuric chloride aluminum is mentioned: [Pg.102]    [Pg.27]    [Pg.336]    [Pg.27]    [Pg.35]    [Pg.95]    [Pg.16]    [Pg.2]    [Pg.275]    [Pg.8]    [Pg.145]    [Pg.341]    [Pg.373]    [Pg.377]    [Pg.16]    [Pg.297]    [Pg.345]    [Pg.55]    [Pg.15]    [Pg.2]    [Pg.256]   
See also in sourсe #XX -- [ Pg.27 , Pg.212 ]




SEARCH



Aluminum chloride

Mercuration Aluminum)

Mercuric chloride

Mercurous chloride

© 2024 chempedia.info