Arsanthrene chloride

Reduction of this acid in concentrated hydrochloric acid solution by sulphur dioxide in the presence of potassium iodide yields arsanthrene chloride, which is oxidised by nitric acid to arsanthrenic acid or di-phenyletie-o-diarsinic add,... 

Reduction of arsanthrene chloride by fuming hydrochloric acid and zinc, or the corresponding oxide by phenylhydrazine, yields armnthrene or diphenylenediarsine, which may be represented as follows ... 

Arsanthrene chloride (II).- The preceding acid is reduced by sulphur dioxide in the j)rescnec of j)otassium iodide in concentrated hydrochloric acid solution. The arsanthrene chloride obtained crystal- Kalb, AnncHen, 1921, 423, 39. 

Arsanthrene chloride in ten times its weight of warm nitric acid (density 1-38) is heated until no more nitrous fumes escape. An equal volume of water is then added and the product obtained recrystalliscd from hot dilute nitric acid (density 1 2). Large, ((olourless prisms separate (probably a dinitrate), which fall to a chalky imwdcr on washing with water. The acid does not melt at 3(i0 and is sparingly soluble in all solvents. 

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