Carbon disulphide, decomposition

V,/V-Disubstituted thioformamides, R1R2NCH=S, are obtained from primary or secondary amines and dimethylthioformamide at 110°C. Aromatic amines do not react for electronic reasons nor does A-methylcyclohexylamine because of steric hindrance323. Decomposition of carbon disulphide in a high-voltage discharge gives CS, which reacts... 

Dipyridino-palladic Iodo-chloride, [Pd py2]IgCl2, crystallises in brown needles and is stable in the dry state in air. On boiling with potassium hydroxide complete decomposition takes place and a residue of palladous iodide remains. If shaken with pure carbon disulphide, two atoms of iodine are removed and dichloro-dipyridino-palladium remains.1... 

Nitrogen dioxide was used in mixtures with such combustibles as paraffin (without aromatic compounds), carbon disulphide or nitrobenzene. These substances were used in the proportions necessary to give complete decomposition into C02, H20 and N2, thus permitting full utilization of the oxygen present in the nitrogen dioxide. To prevent the solidification of nitrobenzene at low temperatures a binary combustible constituent, e.g. a mixture of nitrobenzene with carbon disulphide, was used. 

Insoluble Amorphous Sulphur is produced, usually together with some sulphur soluble in carbon disulphide, by many reactions in which sulphur is set free. The slow decomposition of sulphur chloride or bromide by water, which may require several days for completion, gives a very stable form of insoluble sulphur.8 The action of mineral acids on... 

The hydrogen polysulphides arc miscible with benzene, toluene, chloroform, bromofomi, carbon disulphide, ether and heptane, giving relatively stable solutions,5 and the use of such solutions has been suggested in place of sulphur chloride for the vulcanisation of caoutchouc at the ordinary temperature. The addition of alcohol to the benzene solutions induces rapid decomposition, with formation of nacreous sulphur, which slowly undergoes conversion into ordinary sulphur (p. 25). Ketones, nitrobenzene, aniline and pyridine also catalyse the decomposition. 

A sulphide C2Ss is described by Low4 as a brown, odourless, amorphous substance, only sparingly soluble in carbon disulphide. It is said to be formed during the thermal decomposition of the disulphide5 (see p. 261). 

At 800° C. reaction (2) appears to proceed slowly in either direction, while (1) is very rapid. The fact that the degree of dissociation in (1) is. independent of the amounts of carbon dioxide and carbon disulphide present, shows that carbon monoxide and sulphur are primary products of the decomposition of carbonyl sulphide and are not formed secondarily from the carbon dioxide and carbon disulphide. At temperatures below 400° C. decomposition according to equation (1) is not evident, while at 900° C. it reaches a maximum (64 per cent.) reaction (2) reaches a maximum at about 600° C., at which point 43 per cent, of the carbonyl sulphide is decomposed in this way and 16 per cent, according to reaction (1). The carbon monoxide equilibrium depends upon the pressure, whilst the carbon dioxide equilibrium does not. Nearly all the reactions involved in the thermal decomposition of carbonyl sulphide depend greatly on catalytic influences. Quartz is a pronounced catalyst for reaction (2), but has little influence on reaction (1). Carbonyl sulphide is comparatively rapidly decomposed in quartz vessels, but is stable when kept in glass apparatus. The viscosity of gaseous carbonyl sulphide is as follows x... 

The monochloride is soluble in various inert organic liquids, more particularly in benzene, chloroform, carbon tetrachloride and carbon disulphide, without undergoing chemical change. It is an exothermic compound, its heat of formation from gaseous chlorine and the amorphous modification of selenium being 22-1 Cals.1 Water causes a gradual decomposition of the chloride, selenium dioxide and selenium being formed 2... 

It is a very deep red liquid having a density of 3-60 at 15° C. its odour is unpleasant. It is soluble in carbon disulphide and in chloroform and is, in its turn, a solvent for selenium. When heated, partial decomposition occurs, with formation of bromine and the tetrabromide, distillation taking place at 225° C. 

Although stable in dry air, the tetrachloride is gradually decomposed by moisture it deliquesces, giving an oxychloride. This oxychloride is probably only a mixture of tetrachloride and dioxide.3 With a larger quantity of water the tetrachloride dissolves, giving rise finally to tellurium dioxide. It is soluble without decomposition in aqueous hydrochloric acid (from which an unstable compound HCl.TeCl4.5H20 crystallises at —30° C.), also in carbon disulphide and sulphur monochloride.4... 

A tellurium analogue of carbon disulphide has not been isolated. A product described as carbon ditelluride 1 has been shown to consist of the sulphidotelluride and its decomposition products. 

Arsenic tribromide dissolves in many organic liquids,15 such as carbon disulphide, methylene iodide16 and benzene in the last named the decomposition voltage is 0-50 volt.17 In solutions in diethyl ether18 the electrical conductance at 18° C. rapidly increases with increase in the bromide concentration up to 95 per cent., after which it quickly falls to... 

The crystals dissolve in carbon disulphide and ebullioscopic measurements indicate1 that the molecular formula is As2I4 they also dissolve in ether, alcohol and chloroform. When exposed to air, these solutions darken in colour owing to the formation of the triiodide, and the diiodide cannot be recovered bv evaporation owing to complete decomposition. Boiling acetic anhydride also dissolves the crystals but, on cooling, a yellow substance which appears to contain a derivative of the triiodide separates. The diiodide is also decomposed by pyridine with separation of arsenic, the triiodide being found in solution. 

Arsenic Pentiodide ( ), Asls.—When a mixture of arsenic and iodine in the requisite proportions is heated in an atmosphere of carbon dioxide in a sealed tube at 150° C., a brown crystalline product is obtained.3 The crystals, which melt at 70° C. and have density 3-93, are soluble in water, carbon disulphide, alcohol, ether and chloroform. The solution in carbon disulphide yields, when allowed to crystallise, a mixture of arsenic triiodide and iodine. The latter is readily lost from the pentiodide, and heating at 100° C. in nitrogen in a sealed tube brings about the decomposition. Like the triiodide, the pentiodide dissolves boron tribromide.4... 

Di-a-naphthyl selenium dibromide, (C10H7)2SeBr2, is prepared in the usual manner. It forms wThite needles, melting at 183° C. with decomposition, soluble in amyl alcohol but best recrystallised from carbon disulphide. The halogen may be removed by alkali, but only di-a-naphthyl selenide results, no selenoxide being isolated as in the preceding cases. 

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