Arsenous trichloride

Arsenic trichloride is not completely hydrolysed by water, and in solution the following equilibrium is set up ... 

The success of the Bart reaction when applied to nuclear- substituted anilines is often much affected by the pH of the reaction-mixture. Furthermore, the yields obtained from some m-substituted anilines, which under the normal conditions are usually low, arc considerably increased by the modifications introduced by Scheller, and by Doak, in which the diazotisation is carried out in ethanolic solution followed by reaction with arsenic trichloride in the presence of a cuprous chloride or bromide catalyst. 

Arsenic Peroxides. Arsenic peroxides have not been isolated however, elemental arsenic, and a great variety of arsenic compounds, have been found to be effective catalysts ia the epoxidation of olefins by aqueous hydrogen peroxide. Transient peroxoarsenic compounds are beheved to be iavolved ia these systems. Compounds that act as effective epoxidation catalysts iaclude arsenic trioxide, arsenic pentoxide, arsenious acid, arsenic acid, arsenic trichloride, arsenic oxychloride, triphenyl arsiae, phenylarsonic acid, and the arsenates of sodium, ammonium, and bismuth (56). To avoid having to dispose of the toxic residues of these reactions, the arsenic can be immobi1i2ed on a polystyrene resia (57). 

Arsenic trichloride (arsenic(III) chloride), AsQ. is the most common and important haUde of arsenic. It may be formed by spontaneous combination of the elements and, in addition, by the following reactions (/) chlorine with arsenic trioxide (2) sulfur monochloride, 82(11, or a mixture of S2CI2 chlorine, with arsenic trioxide and (J) arsenic trioxide with concentrated hydrochloric acid or with a mixture of sulfuric acid and a chloride. 

Other methods for preparing tertiary arsiaes have been employed, but they have limited usefiilness. These methods include the cleavage of quaternary arsonium compounds (68), the cyclodehydrohalogenation of haloarsines (69), the reaction of dia2onium salts with arsenic trichloride in the presence of a metal such as 2inc or iron (70), and the disproportionation of halo- or dihaloarsines (71). 

Arsenin and Its Derivatives. Arsenin (arsabenzene) [289-31-6], C H As, the arsenic analogue of pyridine, can be prepared by the treatment of l,4-dihydro-l,l-dibutylstaimabenzene with arsenic trichloride (118) ... 

The Bart reaction is successful with a wide variety of aromatic and heterocycHc amines. A variation in which an aromatic amine, in the presence of arsenic trichloride, is dia2oti2ed in an organic solvent (the ScheUer reaction) has also found wide appHcation. Both arsonic and arsinic acids can be prepared by the ScheUer reaction which often gives better yields than the Bart reaction with electron-attracting substituents on the aromatic ring. For the commercial preparation of 4-aminophenylarsonic acid [98-50-0] (arsaniUc acid), C HgAsNO, and 4-hydroxyphenylarsonic acid [98-14-6] C H AsO, the Bnchamp reaction is used ... 

Arsenic trichloride (butter of arsenic) [7784-34-1 ] M 181.3, b 2S°/llmm, 130.0°. Refluxed with arsenic for 4h, then fractionally distd. The middle fraction was stored with sodium wire for two days, then again distd [Lewis and Sowerby J Chem Soc 336 1957], Fumes in moist air and readily hydrolysed by H2O. POISONOUS. 

Lower respiratory Phosgene nitrogen dioxide arsenic trichloride. ... 

Arsenic(III) sulphide, As2S3 Discussion. The arsenic must be present as arsenic(III), In this condition [ensured by the addition of, for example, iron(II) sulphate, copper(I) chloride, pyrogallol, or phosphorous(III) acid] arsenic may be separated from other elements by distillation from a hydrochloric acid solution, the temperature of the vapour being held below 108 °C arsenic trichloride (also germanium chloride, if present) volatilises and is collected in water or in hydrochloric acid. 

Arsenic standards. Prepare a 1 mgL-1 working standard solution from a 1000 mg L-1 SpectrosoL solution of arsenic trichloride in a 4M hydrochloric acid. 

The Nesmeyanov reaction can also be used for arylarsine syntheses. Usually double salts of diazonium chlorides with zinc chloride are treated with arsenic trichloride and zinc dust in acetone (Hanby and Waters, 1946). Nesmeyanov s school used mainly double salts with ferric chloride and iron powder (Nesmeyanov and Makarova, 1950 Reutov and BundeP, 1955). 

C21-0068. Arsenic trichloride can act both as a Lewis acid and as a Lewis base. Explain why this is so and write a balanced equation for each using BF3 and Cl as reaction partners. 

Arsenic trichloride Gallium arsenide Potassium arsenate Arsine Arsenic add Sodium arsenate Sodium arsenite CaicKjm arsenate Arsenic trioxide Arsenic pwtoxide Arsenic bisulphide Arsenic pentasulphide Arsenic hemiselenide... 

Arsenic trichloride 7784-34-1 Organic synthesis Pharmaceuticals Insecticides Ceramics... 

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