Arsenic trichloride, reaction

Arsonic acids have been prepared from readily available compounds such as arsenic(III) oxide and arsenic trichloride. Reaction of sodium arsenite with alkyl halides has been named the Meyer reaction, and reaction with arenediazonium salts the Bart reaction. In addition, some modifications have been made for the preparation of arsonic acids. Some examples are shown in equations 326 and 327. ... 

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). 

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 ... 

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. 

Reaction with chlorine produces arsenic trichloride and sulfur chloride 2AS2S3 + 9CI2 4AsCl3 + 3S2CI2... 

Arsenic triiodide is prepared by treating elemental arsenic with a solution of iodine in carbon disulfide. Alternatively, it can be precipitated out from a hot solution of arsenic trioxide or arsenic trisulfide in hydrochloric acid on treatment with potassium or sodium iodide. Also, it is made by the reaction of arsenic trichloride with potassium iodide. 

Reactions with fluorine and chlorine give arsenic trifluoride AsFs and arsenic trichloride AsCls, respectively. 

Similarly, arsenic tribromide AsBrs forms when the trioxide reacts with bromine vapors. Reaction with concentrated HCI under heating produces arsenic trichloride. 

Arsine is produced by the reaction of arsenic trichloride, arsenic trioxide or any inorganic arsenic compound with zinc and sulfuric acid. It is also made by treating a solution of sodium arsenide or potassium arsenide in liquid ammonia with ammonium bromide ... 

A. Triphenylarsine. In a 2-1. round-bottomed three-necked flask is placed 130 g. (5.65 gram atoms) of powdered sodium covered with 900 ml. of benzene. The flask is fitted with an Allihn condenser, a mercury-sealed mechanical Hershberg stirrer, and a 500-ml. dropping funnel in which is placed a mixture of 170 g. (0.94 mole) of arsenic trichloride and 272 g. (2.42 moles) of chlorobenzene. About 10 ml. of the arsenic trichloride-chlorobenzene mixture is dropped into the flask, and the reaction mixture is stirred and heated on a steam bath until it darkens and boils spontaneously. The steam bath is removed, and the remainder of the arsenic trichloride-chlorobenzene mixture is added drop-wise, with stirring, over a period of 1-1.5 hours at such a rate that gentle boiling is maintained (Note 1). When the addition is complete, the mixture is stirred and heated under reflux on a steam bath for 12 hours. 

If the addition of the arsenic trichloride-chlorobenzene mixture is too rapid, the reaction becomes vigorous and must be moderated with a cooling bath. 

The halides, GaQs, AlBrs, A1C13, and FeCl3, very probably also exist in dimeric form. With these halides, however, the complexation reaction with the azide is the fast step so that no square-root term is found in the kinetic equation. Arsenic trichloride, arsenic tribromide, phosphorus trichloride, and phosphorus pentachloride were without effect on the rate of decomposition of benzoyl azide. Finally, the authors have observed that the catalytic influence of boron tribromide was much higher than all the other halides. Its rate constant was estimated to be about 18 times larger than that for gallium chloride. 

With pressures up to 150 atm. the quantity of arsenic displaced by hydrogen from solutions of arsenic trichloride in hydrochloric acid is proportional to the pressure. Between 15 and 250 atm., and with solutions not exceeding normal concentration, the reaction is one of the... 

The activating energy of the replacement is calculated to be 28,000 2000 calories. It is estimated that the displacement of 1 per cent, of arsenic from a normal solution of arsenic trichloride at room temperature and 100 atm. of hydrogen would require 1140 years. Increase in the concentration of hydrochloric acid accelerates the reaction, which is inhibited by the presence of sodium chloride, and the reaction appears to be ionic rather than molecular.3... 

This reaction does not proceed in carbon tetrachloride solution.10 Retgers 11 stated that the solid hydride resulted when arsine was heated or when the flame of arsine impinged on a cold plate but other observers 12 maintain that arsenic alone is produced. A solid hydrogen-containing product has also been obtained by the action of zinc, in the presence of sulphuric and nitric acids, on arsenious oxide,13 and by the action of arsine on solid potassium hydroxide,14 followed by the addition of water. A good yield (up to 98 per cent.) of the hydride in a comparatively pure state may be obtained by mixing an ether solution of stannous chloride with a solution of arsenic trichloride in dilute hydrochloric acid.15 The reaction is ... 

Arsenic Trichloride, AsC13, was discovered in 1648 by Glauber,4 who obtained it by heating in a retort a mixture of white arsenic, common salt and sulphuric acid a thick oil, which he designated butter of arsenic, collected in the receiver.5 The compound is produced in many reactions and is usually formed when arsenic and its compounds are... 

By direct action of chlorine on arsenic. When powdered arsenic is sprinkled into chlorine gas,1 or into liquid chlorine near its boiling point,2 union occurs with incandescence and a white cloud of the trichloride is formed. If the gas is passed over arsenic in a tube connected with a receiver immersed in a freezing mixture, the powder which condenses is yellow, owing to excess of chlorine the latter may be removed by distillation from powdered arsenic. The reaction is accelerated by the addition of a trace of bromine or of alkali halide.3 When chlorine is passed into a solution of yellow arsenic in carbon disulphide, brown arsenic is first precipitated, which is then converted to arsenic trichloride.4... 

In order to obtain specimens of arsenic trichloride sufficiently pure for atomic weight determinations, Krepelka fractionally distilled three times in nitrogen the product from the reaction of pure metallic arsenic and dry chlorine. The distillate was then fraetioned in vacuo, the middle fraction being filled into bulbs.6... 

Two-thirds of the requisite amount of arsenious oxide are first added and the remainder after the reaction has progressed for a time, the gas being passed continuously. The arsenic trichloride may be distilled off and does not require purification. The reaction is somewhat violent, however. Arsenic trichloride may also be prepared conveniently by passing carbonyl chloride over a mixture containing 80 per cent, of arsenious oxide and 20 per cent, of carbon heated at 200° to 260° C. the yield is almost quantitative.15... 

By the action of chlorine and chlorine compounds on arsenic pentoxide. Arsenic trichloride is formed when chlorine is passed over the heated oxide.16 Hydrogen chloride reacts at ordinary temperatures, but not at -20° C.17 Aqueous hydrochloric acid, or sulphuric acid and a metallic chloride, also reacts with the oxide or with alkali arsenates to produce arsenic trichloride. The reaction with hydrochloric acid is greatly influenced by catalysts such as ferrous sulphate18 or chloride,19 potassium bromide20 or iodide,21 hydrobromic acid,22 methyl alcohol23... 

By the action of chlorine and chlorine compounds on the sulphides of arsenic. By passing chlorine over the dry sulphides, realgar or orpiment, at 130° to 140° ., theoretical yields of arsenic trichloride and of sulphur dichloride are obtained.5 The trisulphide reacts with hydrogen chloride in the cold, but chlorination by means of hydrochloric acid is difficult, only a small quantity of the chloride being volatilised.7 The reaction is facilitated by the presence of ferric chloride,8 cuprous chloride or potassium antimonyl tartrate.9 Other chlorinating agents, effective with the sulphides, are sulphur mono-chloride,10 a mixture of ammonium chloride and nitrate,11 and mercuric chloride.12... 

Concentrated hydrochloric acid also dissolves the trichloride, about 100 g. of the latter dissolving in 1 litre of acid at 100° C.7 Dissolution in hydriodic acid is accompanied by evolution of heat and the triiodide is formed.8 Ethyl iodide reacts similarly.9 Double decomposition reactions occur w hen arsenic trichloride is heated with phosphorus triiodide, stannic iodide or germanium iodide, the reactions being complete.10 Similarly, potassium iodide heated with arsenic trichloride in a sealed tube at 210° C., and potassium bromide at 180° to 200° C., form respectively arsenic triiodide and tribromide.11 Stannous chloride, added to the solution in hydrochloric acid, causes reduction to arsenic (see p. 29). Arsenic trichloride may be completely separated from germanium chloride by extraction with concentrated hydrochloric acid.12 Ammonium, sodium and cobaltic chlorides react with arsenic trichloride to form additive compounds with magnesium, zinc and chromic chlorides there is no reaction.13... 

Phosphorus dissolves in arsenic trichloride on warming without reaction and is deposited on cooling.8 If the mixture is heated in the presence of aluminium chloride at 130° to 150° C. for 40 minutes, a brownish-red compound of composition A1As3C13 results,9 from which, however, aluminium chloride can readily be removed by water or ammonia, leaving a residue of finely divided black arsenic. If the compound is heated to 190° C. in the absence of air, it turns black as arsenic trichloride and aluminium chloride distil off and a bright grey mixture of arsenic and arsenide remains. It has been suggested that the arsenic is co-ordinatively bound, and that the compound may be /Ass... 

Free arsenic is also produced owing to the reducing action of the arsine. If the tertiary arsine is heated with arsenic trichloride under pressure at a high temperature, the following reaction takes place—... 

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