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Copper anilines

Another interesting observation was that hydrazobenzene could be almost quantitatively converted to azobenzene under reaction conditions. These facts led Kinoshita to propose a mechanism in which a copper aniline complex is formed. Oxidation then occurs in the coordination sphere to give the coordinated radical, [CeHsNH] which dimerizes to hydrazobenzene. [Pg.51]

Required Copper sulphate, 28 g. sodium chloride, 9-5 g. sodium bisulphite, 14 g. hydrochloric acid, 70 ml. aniline, 20 ml. sodium nitrite, 17 g. [Pg.189]

Required Aniline, 30 ml. onrhlorobenzoic acid, 8 g. potassium carbonate, 8 g. powdered copper oxide, 0 4 g. [Pg.217]

Prepare a mixture of 30 ml, of aniline, 8 g. of o-chloro-benzoic acid, 8 g. of anhydrous potassium carbonate and 0 4 g. of copper oxide in a 500 ml. round-bottomed flask fitted with an air-condenser, and then boil the mixture under reflux for 1 5 hours the mixture tends to foam during the earlier part of the heating owing to the evolution of carbon dioxide, and hence the large flask is used. When the heating has been completed, fit the flask with a steam-distillation head, and stcam-distil the crude product until all the excess of aniline has been removed. The residual solution now contains the potassium. V-phenylanthrani-late add ca. 2 g. of animal charcoal to this solution, boil for about 5 minutes, and filter hot. Add dilute hydrochloric acid (1 1 by volume) to the filtrate until no further precipitation occurs, and then cool in ice-water with stirring. Filter otT the. V-phcnylanthranilic acid at the pump, wash with water, drain and dry. Yield, 9-9 5 g. I he acid may be recrystallised from aqueous ethanol, or methylated spirit, with addition of charcoal if necessary, and is obtained as colourless crystals, m.p. 185-186°. [Pg.217]

Required Arsenious oxide, 27 g. aniline, 20 ml. (20 g.) anhydrous sodium carbonate, 55 g. crystalline copper sulphate,... [Pg.312]

N-Phenylanthranilic acid may be prepared by the action of aniline upon c-chlorobenzoic acid in the presence of anhydrous potassium carbonate and a little copper oxide ... [Pg.991]

Transition-Metal Catalyzed Cyclizations. o-Halogenated anilines and anilides can serve as indole precursors in a group of reactions which are typically cataly2ed by transition metals. Several catalysts have been developed which convert o-haloanilines or anilides to indoles by reaction with acetylenes. An early procedure involved coupling to a copper acetyUde with o-iodoaniline. A more versatile procedure involves palladium catalysis of the reaction of an o-bromo- or o-trifluoromethylsulfonyloxyanihde with a triaLkylstaimylalkyne. The reaction is conducted in two stages, first with a Pd(0) and then a Pd(II) catalyst (29). [Pg.87]

Aromatic amines form addition compounds and complexes with many inorganic substances, such as ziac chloride, copper chloride, uranium tetrachloride, or boron trifluoride. Various metals react with the amino group to form metal anilides and hydrochloric, sulfuric, or phosphoric acid salts of aniline are important intermediates in the dye industry. [Pg.229]

A AlI lation. A number of methods are available for preparation of A/-alkyl and A[,A/-dialkyl derivatives of aromatic amines. Passing a mixture of aniline and methanol over a copper—zinc oxide catalyst at 250°C and 101 kPa (1 atm) reportedly gives /V-methylaniline [100-61-8] in 96% yield (1). Heating aniline with methanol under pressure or with excess methanol produces /V, /V-dimethylaniline [121 -69-7] (2,3). [Pg.229]

The predominant process for manufacture of aniline is the catalytic reduction of nitroben2ene [98-95-3] ixh. hydrogen. The reduction is carried out in the vapor phase (50—55) or Hquid phase (56—60). A fixed-bed reactor is commonly used for the vapor-phase process and the reactor is operated under pressure. A number of catalysts have been cited and include copper, copper on siHca, copper oxide, sulfides of nickel, molybdenum, tungsten, and palladium—vanadium on alumina or Htbium—aluminum spinels. Catalysts cited for the Hquid-phase processes include nickel, copper or cobalt supported on a suitable inert carrier, and palladium or platinum or their mixtures supported on carbon. [Pg.231]

Aniline is slightly corrosive to some metals. It attacks copper, brass, and other copper alloys, and use of these metals should be avoided in equipment that is used to handle aniline. For appHcations in which color retention is critical, the use of 400-series stainless steels is recommended. [Pg.232]

The vapor-phase conversion of aniline to DPA over a soHd catalyst has been extensively studied (18,22). In general, the catalyst used is pure aluminum oxide or titanium oxide, prepared under special conditions (18). Promoters, such as copper chromite, nickel chloride, phosphoric acid, and ammonium fluoride, have also been recommended. Reaction temperatures are usually from 400 to 500°C. Coke formed on the catalyst is removed occasionally by burning. In this way, conversions of about 35% and yields of 95% have been reported. Carba2ole is frequently a by-product. [Pg.244]

The chemical production of aminophenols via the reduction of nitrobenzene occurs in two stages. Nitrobenzene [98-95-3] is first selectively reduced with hydrogen in the presence of Raney copper to phenylhydroxylamine in an organic solvent such as 2-propanol (37). With the addition of dilute sulfuric acid, nucleophilic attack by water on the aromatic ring of /V-phenylhydroxylamine [100-65-2] takes place to form 2- and 4-aminophenol. The by-product, 4,4 -diaminodiphenyl ether [13174-32-8] presumably arises in a similar manner from attack on the ring by a molecule of 4-aminophenol (38,39). Aniline [62-53-3] is produced via further reduction (40,41). [Pg.311]

Methyl violet [8004-87-3] Cl Basic Violet 1 (17), is made by the air oxidation of dimethyl aniline in the presence of salt, phenol, and a copper sulfate catalyst. Initially, some of the dimethyl aniline is oxidized to formaldehyde and /V-methyl aniline under those conditions. The formaldehyde then reacts with dimethyl aniline to produce N,N,]S7,1S7-tetramethyldiaminodiphenylmethane, which is oxidized to Michler s hydrol [119-58-4]. The hydrol condenses with... [Pg.272]

The Dow Chemical Company in the mid-1920s developed two processes which consumed large quantities of chlorobenzene. In one process, chlorobenzene was hydrolyzed with ammonium hydroxide in the presence of a copper catalyst to produce aniline [62-53-3J. This process was used for more than 30 years. The other process hydrolyzed chlorobenzene with sodium hydroxide under high temperature and pressure conditions (4,5) to product phenol [108-95-2]. The LG. Earbenwerke in Germany independentiy developed an equivalent process and plants were built in several European countries after World War II. The ICI plant in England operated until its dosing in 1965. [Pg.46]

Yields depend on the reactivity of the amines and the choice of reaction conditions, including the choice of copper catalyst. Generally, the reactivity increases with increasing amine basicity. Thus, i7n7-toluidine (pTf = 5.1) reacts four times faster than aniline (pif = 4.7) (27). StericaHy hindered amines such as 3,5-di-amino-2,4,6-trimethylbenzenesulfonic acid react very slowly. [Pg.310]

An example of the use of copper as a catalyst is Acid Blue 25 [6408-78-2] (Cl 62055) in which l-amino-2-sulfonic-4-bromoanthraquinone is condensed with aniline using copper salts (Ullmann reaction) (314). Another example is oxidation to the tria2ole of Direct YeUow 106 [12222-60-5] (Cl 40300) (315,316). [Pg.386]

The reaction between copper(I) acetylides and o-halogenophenols or -anilines provides a general and convenient route to 2-substituted benzofurans or indoles (Scheme 71g) (66JOC4071). [Pg.129]

Benzanthrone has been prepared by three general methods, the first of which is generally regarded as the best (i) by heating a reduction product of anthraquinone with sulfuric acid and glycerol,1 or with a derivative of glycerol, or with acrolein. The anthraquinone is usually reduced in sulfuric acid solution, just prior to the reaction, by means of aniline sulfate, iron, , or copper. It has also been prepared (2) by the action of aluminum or ferric chloride on phenyl-a-naphthyl ketone, and (3) from i-phenylnaphthalene-2-carboxylic acid. ... [Pg.6]

Salicyl-u-toluide has been prepared only by the action of phosphorus oxychloride upon a mixture of salicylic acid and o-toluidine. The useful methods of preparation of salicylanilide are by the interaction of salicylic acid and aniline in the presence of phosphorus trichloride, by heating phenyl salicylate and aniline, and from o-hydroxybenzamide and bromobenzene in the presence of small amounts of sodium acetate and metallic copper. A number of these and other anilides have been described. ... [Pg.94]

Copper, chromium, iron, most metals or their salts, any flammable liquid, combustible materials, aniline, nitromethane Fuming nitric acid, oxidizing gases Acetylene, ammonia (anhydrous or aqueous)... [Pg.233]

An alternative way to produce aniline is through ammonolysis of either chlorobenzene or phenol. The reaction of chlorobenzene with aqueous ammonia occurs over a copper salt catalyst at approximately 210°C and 65 atmospheres. The yield of aniline from this route is also about 96% ... [Pg.279]


See other pages where Copper anilines is mentioned: [Pg.1841]    [Pg.1841]    [Pg.35]    [Pg.189]    [Pg.607]    [Pg.67]    [Pg.329]    [Pg.141]    [Pg.231]    [Pg.244]    [Pg.255]    [Pg.258]    [Pg.311]    [Pg.420]    [Pg.257]    [Pg.395]    [Pg.48]    [Pg.12]    [Pg.135]    [Pg.211]    [Pg.33]    [Pg.871]    [Pg.23]    [Pg.389]    [Pg.70]    [Pg.3]   


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