“The reduction was carried out in an iron tank lined with tiles and a temperature of 80° was maintained. About 8 hrs. were required for the reaction. The diphenylarsenic acid on reduction by the sulfur dioxide was converted into diphenylarsenous oxide which, in the presence of the hydrochloric acid, was converted into diphenylchloroarsine, which separated as an oil. The oil was next removed and heated in the best vacuum obtainable until it was dry and free from hydrochloric acid. The compound melted at 34°. It was placed in iron tanks for shipment. The yield of diphenylchloroarsine calculated from the aniline used was from 25 to 30 per cent of the theoretical. No marked trouble was observed in handling the materials and no serious poisoning cases were reported.
Diphenylcyanoarsine
“This compound was prepared by treating diphenylchloroarsine with a saturated aqueous solution of potassium or sodium cyanide.
(C₆H₅)₂AsCl + NaCN = (C₆H₅)₂AsCN + NaCl.
Five per cent excess of the alkaline cyanide was used. The reaction was carried out at 60° with vigorous stirring. The yield was nearly theoretical.
Ethyldichloroarsine
“This compound was prepared at Höchst from ethylarsenous oxide which was obtained from the Badische Anilin und Soda Fabrik.
“Preparation of Ethylarsenous Oxide—The compound was prepared by treating sodium arsenite with ethyl chloride under pressure. The resulting sodium salt of ethylarsenic acid was converted into the free acid and reduced by sulfur dioxide. The ethylarsenous acid formed in this way lost water and was thereby transformed into ethylarsenous oxide. The reactions involved are as follows:
| C₂H₅Cl + Na₃AsO₃ | = | C₂H₅AsO₃Na₂ + NaCl |
| C₂H₅AsO₃Na₂ + 2 HCl | = | C₂H₅AsO₃H₂ + 2 NaCl |
| C₂H₅AsO₃H₂ + SO₂ + H₂O | = | C₂H₅AsO₂H₂ + H₂SO₄ |
| 2C₂H₅AsO₂H₂ | = | (C₂H₅As)₂O + H₂O. |
“The ethyl chloride used in the preparation was in part made in this factory, and in part received from other sources. As ethyl chloride is an important product used in peace time, it is not, therefore, essentially a war product and its preparation was not described.