Cuprous aluminum chloride

The use of aqueous cuprous-ammonium carbonate and formate solutions was first described in a patent to Badische Anilin and Soda Fabrik (1914). Subsequently, the aqueous process was utilized in many plants and the chemistry of the process was studied extensively. More recently, a process based on the use of cuprous aluminum chloride in an aromatic solvent carrier (the COSORB process) has been developed. The new process is reported to have the advantages of greater complex stability and a lower corrosion rate. Both the aqueous and non-aqueous processes are discussed in the following sections. Although the aqueous process is now seldom used, it is included in the discussion because of its historical and technical interest. A more detailed discussion of the aqueous process is given in previous... 

The COSORB process resembles the copper-ammonium salt process described in the preceding section in that it also uses a copper compound that forms a complex with absorbed CO. It is significantly different, however, in that the ab.sorbent is nonaqueous. The active component is cuprous aluminum chloride (CUAICI4) dissolved in an aromatic base, toluene (Haase, 1975). The absorption-desorption reaction can be represented by the following equation ... 

Cosorb [CO absorb] A process for recovering carbon monoxide by absorption in a solution of cuprous aluminum chloride in toluene. Three stages are involved absorption, desorption, and washing. Invented by Esso Research and Engineering Company and then developed by Tenneco Chemicals in the early 1970s. Piloted in... 

In the presence of aluminum chloride and a small amount of cuprous haUde, a mixture of hydrogen chloride and carbon monoxide serves as a formyl a ting agent of aromatics (Gattermann-Koch reaction) (107) ... 

There are a few reports of poly(naphthalene) thin films. Yoshino and co-workers. used electrochemical polymerization to obtain poly(2,6-naphthalene) film from a solution of naphthalene and nitrobenzene with a composite electrolyte of copper(II) chloride and lithium hexafluoroarsenate. Zotti and co-workers prepared poly( 1,4-naphthalene) film by anionic coupling of naphthalene on. platinum or glassy carbon electrodes with tetrabutylammonium tetrafluoroborate as an electrolyte in anhydrous acetonitrile and 1,2-dichloroethane. Recently, Hara and Toshima prepared a purple-colored poly( 1,4-naphthalene) film by electrochemical polymerization of naphthalene using a mixed electrolyte of aluminum chloride and cuprous chloride. Although the film was contaminated with the electrolyte, the polymer had very high thermal stability (decomposition temperature of 546°C). The only catalyst-free poly(naphthalene) which utilized a unique chemistry, Bergman s cycloaromatization, was obtained by Tour and co-workers recently (vide infra). 

The amine is then used to introduce a nitrile by diazotization followed by treatment of the diazonium salt with cuprous cyanide (180) the methyl ether is then cleaved by means of aluminum chloride. Treatment of the phenolic ketone 181 with benzoyl chloride and sodium benzoate serves to build up the chromone ring (182). The nitrile is next hydrolyzed to the acid with sulfuric acid. Esterification of the carboxyl as—its acid chloride—with N-(2-hydroxyethyl)piperi-... 

Nitration of hydroxypropiophenone (7-1) followed by conversion of the phenol to its methyl ether by means of methyl iodide provides the intermediate (7-2) the nitro group is then reduced to the corresponding amine (7-3) by catalytic reduction. The newly introduced amine is then replaced by a nitrile group by successive conversion to the diazonium salt by means of nitrous acid followed by treatment with cuprous cyanide (7-4). Reaction with aluminum chloride removes the methyl ether to afford the ortho acylphenol (7-5). This is converted to the chromone (7-6) as above by reaction with benzoyl chloride and sodium benzoate. The nitrile is next hydrolyzed to the carboxylic acid (7-7) by means of sulfuric acid. The acid is then converted to its acid chloride by means of thionyl chloride and that treated with 2-(A -piperidyl)ethanol (7-8). There is thus obtained flavoxate (7-9) [8], a muscle relaxant whose name reflects its flavone nucleus. 

The apparatus is arranged in a hood, as shown in illustration. The narrow reaction bottle (A), of about 500-cc. capacity and having a wide mouth, is provided with an efficient mercury-sealed mechanical stirrer, an inlet tube (BJ for admitting the mixture of gases, and an outlet tube connected with the wash bottle (E). Into (A), contained in a water bath at 20°, is placed 200 g. (2.17 moles) of dry toluene, and then 30 g. (0.15 mole CU2CI2) of cuprous chloride (Note 1) and 267 g. (2 moles AICI3) of finely powdered anhydrous aluminum chloride are added rapidly with active stirring. 

Trimethylbenzaldehyde has been prepared from mes-itylglyoxylic acid,3,4 from mesitylene, nickel carbonyl, and aluminum chloride, and in excellent yield from mesitylene, hydrogen cyanide, and hydrogen chloride, as well as from mesitylene, carbon dioxide, and hydrogen chloride, in the presence of aluminum and cuprous chlorides.6 The above method is that applied to the preparation of other aldehydes by Rosen-mund and Zetzsche.7... 

GATTERMANN-KOCH REACTION. Formulation of hen/cne, alkyl-betuenes. or polycyclic aromatic hydrocarbons with carbon monoxide and hydrochloric acid in the presence of aluminum chloride al high pressure. Addition of cuprous chloride allows Ihe reaction to proceed at atmospheric pressure. 

The epioxazoline is successively treated with chlorine, sodium iodide, cuprous oxide and boron trifluoride to produce the exomethylene compound (V). Methoxylation using chlorine with a methoxide followed by reaction with 1-methyl-lH-tetrazole-5-thiol and partial de-blocking using phosphorous pentachloride converts exomethylene (V) into the nucleus (VI). Acylation of the nucleus with an appropriately blocked side-chain (VII) followed by final de-blocking using aluminum chloride gives moxalactam acid (VIII). 

Aromatic aldehydes are prepared by passing carbon monoxide and dry hydrogen chloride through an ether or nitrobenzene solution of an aromatic hydrocarbon in the presence of a catalyst, commonly aluminum chloride with cuprous chloride as a carrier. The process is illustrated by the synthesis of p-tolualdehyde (51%). A convenient procedure for obtaining an equimolar mixture of anhydrous hydrogen chloride and carbon monoxide consists in dropping chlorosulfonic acid on formic acid, viz.,... 

Gattermann-Koch reaction Aluminum chloride. Cuprous cMoiide. 

Gattermann-Koch reaction. For the conversion of toluene into p-tolylaldehyde, gaseous carbon monoxide and hydrogen chloride are passed into a stirred suspension of aluminum chloride and cuprous chloride. ... 

Oallermamt-hoch synthesis. A procedure for (he synthesis of p-tolualdehyde" calls for stirring a suspension of cuprous chloride and aluminum chloride in toluene... 

The synthesis of benzaldehyde from benzene poses a problem because formyl chloride, the acyl halide required for the reaction, is unstable and cannot be purchased. Formyl chloride can be prepared, however, by means of the Gatterman-Koch formyla-tion reaction. This reaction uses a high-pressure mixture of carbon monoxide and HCl to generate formyl chloride, along with an aluminum chloride-cuprous chloride catalyst to carry out the acylation reaction. 

Tetrahydrofuran freshly distilled from lithium aluminum hydride should be used. A commercial product with a peroxide content giving a positive iodine test must be treated with about 0.3% of cuprous chloride (boiling for 30 minutes and distillation) before the addition of the hydride. 

Alkyl bromides and especially alkyl iodides are reduced faster than chlorides. Catalytic hydrogenation was accomplished in good yields using Raney nickel in the presence of potassium hydroxide [63] Procedure 5, p. 205). More frequently, bromides and iodides are reduced by hydrides [505] and complex hydrides in good to excellent yields [501, 504]. Most powerful are lithium triethylborohydride and lithium aluminum hydride [506]. Sodium borohydride reacts much more slowly. Since the complex hydrides are believed to react by an S 2 mechanism [505, 511], it is not surprising that secondary bromides and iodides react more slowly than the primary ones [506]. The reagent prepared from trimethoxylithium aluminum deuteride and cuprous iodide... 

Since sodium borohydride usually does not reduce the nitrile function it may be used for selective reductions of conjugated double bonds in oc,/l-un-saturated nitriles in fair to good yields [7069,1070]. In addition some special reagents were found effective for reducing carbon-carbon double bonds preferentially copper hydride prepared from cuprous bromide and sodium bis(2-methoxyethoxy)aluminum hydride [7766], magnesium in methanol [7767], zinc and zinc chloride in ethanol or isopropyl alcohol [7765], and triethylam-monium formate in dimethyl formamide [317]. Lithium aluminum hydride reduced 1-cyanocyclohexene at —15° to cyclohexanecarboxaldehyde and under normal conditions to aminomethylcyclohexane, both in 60% yields [777]. 

One general method for acyl silane synthesis particularly successful for a-cyclopropyl examples (and even an a-cyclobutyl example) involves treatment of acid chlorides with lithium tetrakis(trimethylsilyl) aluminum or lithium methyl tris(trimethylsilyl) aluminium and cuprous cyanide (vide supra, Section III.A.3)77. For example, cyclopropyl acyl silane (23) was obtained in 89% yield by this process. Improved procedures use lithium t-butyldimethylsilyl cuprate78 and a dimethylphenylsilyl zinc cuprate species79,80 as reagents. 

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