Chloride aluminum

Aluminum chloride (A1C13) is a white solid when pure that sublimes on heating and, in the presence of moisture, decomposes with the evolution of hydrogen chloride. 

Anhydrous aluminum chloride is manufactured primarily by the reaction of chlorine vapor on molten aluminum. 

In the process, chlorine is fed in below the surface of the aluminum, and the product sublimes and is collected by condensing. These air-cooled condensers are thin-walled, vertical steel cylinders with conical bottoms. Aluminum chloride crystals form on the condenser walls and are periodically removed, crushed, screened, and packaged in steel containers. 

Aluminum chloride is used in the petroleum industries and various aspects of organic chemistry technology. For example, aluminum chloride is a catalyst in the alkylation of paraffins and aromatic hydrocarbons by olefins and also in the formation of complex ketones, aldehydes, and carboxylic acid derivatives. 

Aluminum chloride, AICI3, is prepared by the reaction of dry chlorine gas with liquid aluminum at 750-800 °C 

Water-free AICI3 acts as a strong Lewis acid in the organic chemistry, especially in Friedel-Crafts-reactions for the alcylation of aromatics, e.g. in the production of ethyl benzene. It is a catalyst for the production of ethyl chloride and is a precursor material for the production of dyes, detergents, resins, aluminum borohydride, lithium aluminum hydride, and of phosphorus and sulfur compounds. 

Aqueous solutions of AICI3 are used as a flocculant in waste water treatment, as catalyst in the textile and paper industry, as a disinfectant and in wood protection. 

The production of metallic aluminum by electrochemical decomposition of AICI3 (ALCOA-process) has not yet reached industrial scale. 

Water-free FeCl2 is obtained by the reaction of dry hydrogen chloride gas with red hot iron powder. It is used as a reducing agent in the production of colours. 

The total production of aluminum chloride in the USA has declined from 72.2 lO t/a (as AICI3) in 1980 to 36.9 10- t/a in 1993. These figures include both the production of anhydrous aluminum chloride and aluminum chloride hexahydrate, AICI3 6H2O, the former having declined in this period from 67 10- t/a to 17.6 10 t/a and the latter having increased in this period from 5.2 10 t/a (as AICI3) to 19.3 - 10 t/a. In 1993 the production of anhydrous aluminum chloride in Western Europe was 29 10 t/a and in Japan was 8 10 t/a. 

Anhydrous aluminum chloride is currently mainly manufactured by chlorination of liquid aluminum in ceramic-lined reaction vessels at 600 to 750°C, gaseous aluminum chloride being fed into condensation chambers. The reductive chlorination of aluminum oxide in the presence of coal (e.g. in the Alcoa process, see Section 3.2.3.2) is also operated industrially. Hydrated aluminum chloride is manufactured by reacting aluminum hydroxide with hydrochloric acid or hydrogen chloride. 

Anhydrous aluminum chloride is used as a nucleation agent in the production of Ti02-pigment by the chloride process. 

In the period 1977 to 1981 a pilot plant for aluminum manufacture from aluminum chloride was operated in the USA by Alcoa. In this period most of the anhydrous aluminum chloride produced in the USA was consumed in this plant. 

Aqueous aluminum chloride is utilized in the production of pharmaceuticals and chemicals and in the manufacture of special papers. 

The Diels-Alder reaction was thought for many years to be only slightly influenced by catalysts. However, in 1960, Yates and Eaton (6) clearly demonstrated that with certain dienophiles, the presence of a molar equivalent of aluminum chloride can cause a remarkable acceleration of the reaction. Providing the diene is not polymerized (7) or otherwise destroyed by the catalyst, the modification can be fruitfully employed to carry out the reaction at lower temperature and for shorter times. 

Anthracene and maleic anhydride with aluminum chloride give the adduct quantitatively in minutes. The product is recrystallized from ethyl acetate, mp 262-263°. 

Equimolar amounts of anthracene,/ -benzoquinone, and aluminum chloride give the faintly yellow adduct in 15 minutes. The product is unstable to heat turning yellow at 207°, turning red at 210°, and slowly charring. When 2 molar equivalents of anthracene are used, the bis adduct is obtained, mp 230°, unobtainable in the absence of the catalyst. 

Bellesia, F. Ghelfi, F. Pagnoni, U. M. Pinetti, A. Synth. Commun. 

Matoba, K. Tachi, M. Itooka, T. Yamazaki, T. Chem. Pharm. Bull. 1986, 34, 2007. 

(a) Ikeda, K. Morimoto, T. Sekiya, M. Cherrc PharrrL Bull. 1980, 28, 1178. (b) Ikeda, K. Terao, Y. Sekiya, M. Cherrc PharrrL Bull. 1981, 29, 1156. 

Physical Data mp 190 °C (193-194 °C sealed tube) sublimes at 180°C 6(2.44gcm-  

Solubility sol many organic solvents, e.g. benzene, nitrobenzene, carbon tetrachloride, chloroform, methylene chloride, nitromethane, and 1,2-dichloroethane insol carbon disulfide. 

Formula AICI3 MW 133.31 Structure and bonding an electron-deficient compound, a Lewis acid, occurs as dimer AI2CI6 in hexagonal crystal form. Above 300 °C, dissociation to monomer AICI3 begins completely dissociates to AICI3 at 1,100°C. 

Aluminum chloride has extensive commercial applications. It is used primarily in the electrolytic production of aluminum. Another major use involves its catalytic applications in many organic reactions, including Friedel-Crafts alkylation, polymerization, isomerization, hydrocracking, oxidation, decarboxylation, and dehydrogenation. It is also used in the production of rare earth chlorides, electroplating of aluminum and in many metal finishing and metallurgical operations. 

White or light-yellow crystalline solid (or amorphous sohd depending on the method of production) odor of HCl hygroscopic melts at 190°C at 2.5 atm sublimes at 181.2°C density 2.44 g/cm at 25°C decomposes in water evolving heat soluble in HCl soluble in many organic solvents, including absolute ethanol, chloroform, carbon tetrachloride and ether slightly soluble in benzene. 

Aluminum chloride is made by chlorination of molten aluminum at temperatures between 650 to 750°C  

A pelletized mixture of clay, lignite and a small amount of NaCl is chlorinated at 900°C, producing gaseous AICI3 (Toth process). Alternatively, alumina is mixed with about 20% by weight carbon and a small amount of sodium 

The direction of the nitrogen stream is reversed, a drying tube filled with PsOb is attached at g, and the AlBra is distilled from 

Colorless, shiny lamellae. Hydrolyzes in moist air. Reacts violently with water (caution ). Soluble in many organic solvents. M.p. 97.5°C, b.p. 255°C d (18°C) 3.205, d (100°C, liq.) 2.64. 

Form Supplied in colorless solid when pure, typically a gray or yellow-green solid also available as a 1.0 M nitrobenzene solution. 

Handling, Storage, and Precautions fumes in air with a strong odor of HCl. AICI3 reacts violently with H2O. All containers should be kept tightly closed and protected from moisture. Use in a fume hood. 

Friedel-Crafts Chemistry. AICI3 has traditionally been used in stoichiometric or catalytic amounts to mediate Friedel-Crafts alkylations and acylations of aromatic systems (eq 1). 

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In a generalized sense, acids are electron pair acceptors. They include both protic (Bronsted) acids and Lewis acids such as AlCb and BF3 that have an electron-deficient central metal atom. Consequently, there is a priori no difference between Bronsted (protic) and Lewis acids. In extending the concept of superacidity to Lewis acid halides, those stronger than anhydrous aluminum chloride (the most commonly used Friedel-Crafts acid) are considered super Lewis acids. These superacidic Lewis acids include such higher-valence fluorides as antimony, arsenic, tantalum, niobium, and bismuth pentafluorides. Superacidity encompasses both very strong Bronsted and Lewis acids and their conjugate acid systems. 

METHOD 2 [105 p725, 106-108]--This is super easy and uses aluminum chloride (AlCIs) for which there are many uses in underground chemistry. The original reference is in German but the master here has translated it for you. There s something about... 

Thomas, C.A., "Anhydrous Aluminum Chloride in Organic Chemistry", (Reinhold, New York, 1941)... 

Butyne trimerizes in the presence of aluminum chloride to give hexamethyl Dewar-benzene (W. Schafer, 1967). Its irradiation leads not only to aromatization but also to hexa-methylprismane (D.M. Lemal, 1966). Highly substituted prlsmanes may also be obtained from the corresponding benzene derivatives by irradiation with 254 nm light. The rather stable prismane itself was synthesized via another hydrocarbon, namely benzvalene, a labile molecule (T. J. Katz, 1971, 1972). 

Recently, Koitai et al. (17) have shown that 5,5-diphenyl-2,4-thiazolidinedithione (15) with aluminum chloride in refluxing toluene gives 4,5-diphenyl-A-4-thia2oline-2-thione (16) (Scheme 7). 3-Methyl-4,5-diphenyl (17) and 4,5-diphenyl-A-4-thia2oline-2-thiones (16) are obtained in very low yields (1 to 5%) as by-products of the reaction between deoxybenzoin. benzoin. l,2-diphenyl-1.2-ethanediol. 1.2-diphenylethanol, or benzil, and Sg in hexamethylphosphoamide (18), The transformation of A-4-thiazoline-2-ones to the corresponding thiones by P2S5 (19) is of little synthetic value since the latter are more easily prepared. 

Alkyl halides react with benzene m the presence of aluminum chloride to yield alkyl benzenes... 

Alkylation of benzene with alkyl halides m the presence of aluminum chloride was discovered by Charles Friedel and James M Crafts m 1877 Crafts who later became president of the Massachusetts Institute of Technology collaborated with Friedel at the Sorbonne m Pans and together they developed what we now call the Friedel-Crafts reaction into one of the most useful synthetic methods m organic chemistry... 

Alkyl halides by themselves are insufficiently electrophilic to react with benzene Aluminum chloride serves as a Lewis acid catalyst to enhance the electrophihcity of the alkylating agent With tertiary and secondary alkyl halides the addition of aluminum chlonde leads to the formation of carbocations which then attack the aromatic ring... 

Secondary alkyl halides react by a similar mechanism involving attack on benzene by a secondary carbocation Methyl and ethyl halides do not form carbocations when treated with aluminum chloride but do alkylate benzene under Friedel-Crafts conditions The aluminum chloride complexes of methyl and ethyl halides contain highly polarized carbon-halogen bonds and these complexes are the electrophilic species that react with benzene... 

Step 1 Once generated by the reaction of tert butyl chloride and aluminum chloride tert butyl cation attacks the TT electrons of benzene and a carbon-carbon bond is formed... 

In an attempt to prepare propylbenzene a chemist alkylated benzene with 1 chloropropane and aluminum chloride However two isomeric hydrocarbons were obtained m a ratio of 2 1 the desired propylbenzene being the minor component What do you think was the major product How did it anse ... 

Alkenyl halides such as vinyl chloride (H2C=CHC1) do not form carbocations on treatment with aluminum chloride and so cannot be used m Friedel-Crafts reactions Thus the industrial preparation of styrene from benzene and ethylene does not involve vinyl chloride but proceeds by way of ethylbenzene... 

Acyl cations form by coordination of an acyl chloride with aluminum chloride followed by cleavage of the carbon-chlonne bond... 

Carboxylic acid anhydrides compounds of the type RCOCR can also serve as sources of acyl cations and m the presence of aluminum chloride acylate benzene One acyl unit of an acid anhydride becomes attached to the benzene ring and the other becomes part of a carboxylic acid... 

Direct alkylation of benzene using 1 chlorobutane and aluminum chloride would yield sec butylbenzene by rearrangement and so could not be used... 

Reaction of chlorobenzene with p chlorobenzyl chloride and aluminum chloride gave a mixture of two products in good yield (76%) What were these two products ... 

Aluminum chloride is a stronger Lewis acid than iron(lll) bromide and has been used as a catalyst in electrophilic bromination when as in the example shown the aromatic ring bears a strongly deactivating substituent... 

Carbocations usually generated from an alkyl halide and aluminum chloride attack the aromatic ring to yield alkylbenzenes The arene must be at least as reactive as a halobenzene Carbocation rearrangements can occur especially with primary alkyl hal ides... 

Rearrangement is especially prevalent with primary alkyl halides of the type RCH2CH2X and R2CHCH2X Aluminum chloride induces ionization with rearrangement to give a more stable carbocation Benzylic halides and acyl halides do not rearrange... 

Partial rate factors may be used to estimate product distributions in disubstituted benzene derivatives The reactivity of a particular position in o bromotoluene for example is given by the product of the partial rate factors for the corresponding position in toluene and bromobenzene On the basis of the partial rate factor data given here for Fnedel-Crafts acylation predict the major product of the reaction of o bromotoluene with acetyl chlonde and aluminum chloride... 

When 2 isopropyl 13 5 tnmethylbenzene is heated with aluminum chloride (trace of HCl present) at 50°C the major material present after 4 h is 1 isopropyl 2 4 5 tnmethylbenzene Sug gest a reasonable mechanism for this isomerization... 

When a dilute solution of 6 phenylhexanoyl chloride in carbon disulfide was slowly added (over a period of eight days ) to a suspension of aluminum chloride in the same solvent it yielded a product A (C12H14O) in 67% yield Oxidation of A gave benzene 1 2 dicarboxyhc acid... 

One of the most useful reac tions of acyl chlorides was presented in Section 12 7 Friedel-Crafts acylation of aromatic rings takes place when arenes are treated with acyl chlorides in the presence of aluminum chloride... 

Isopropylbenzene is prepared by the Friedel-Crafts alkylation of benzene y using isopropyl chloride and aluminum chloride (Section 12 6) j... 

As shown in the sixth entry of Table 24 4 C acylation of phenols is observed under the customary conditions of the Friedel-Crafts reaction (treatment with an acyl chloride or acid anhydride m the presence of aluminum chloride) In the absence of aluminum chloride however O acylation occurs instead... 

The preference for O acylation of phenols arises because these reactions are kmetically controlled O acylation is faster than C acylation The C acyl isomers are more stable how ever and it is known that aluminum chloride is a very effective catalyst for the conversion of aryl esters to aryl ketones This isomerization is called the Fries rearrangement... 

Thus ring acylation of phenols is observed under Friedel-Crafts conditions because the presence of aluminum chloride causes that reaction to be subject to thermodynamic (equi librium) control... 

Friedel-Crafts alkylation (Section 12 6) An electrophilic aro matic substitution in which an aromatic compound reacts with an alkyl halide in the presence of aluminum chloride An alkyl group becomes bonded to the nng... 

Examples 3CdS04 8H2O, cadmium sulfate—water (3/8) Al2(S04)3 K2SO4 24H2O, aluminum sulfate—potassium sulfate—water (1/1/24) AICI3 4C2H5OH, aluminum chloride—ethanol (1/4). 

Chloroform Aluminum, magnesium, potassium, sodium, aluminum chloride, ethylene, powerful oxidants... 

Ethylene oxide Acids and bases, alcohols, air, 1,3-nitroaniline, aluminum chloride, aluminum oxide, ammonia, copper, iron chlorides and oxides, magnesium perchlorate, mercaptans, potassium, tin chlorides, alkane thiols... 

Phenol Butadiene, peroxodisulfuric acid, peroxosulfuric acid, aluminum chloride plus nitrobenzene... 

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