Diphenylchloroarsine is the organoarsenic compound with the formula (C₆H₅)₂AsCl. This odorless, toxic liquid was once used as harassing agent. It is also an intermediate in the preparation of other organoarsenic compounds. The molecule consists of a pyramidal As(III)

Arsenic

Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

 center attached to two phenyl rings and one chloride

Chloride

The chloride ion is formed when the element chlorine, a halogen, picks up one electron to form an anion Cl−. The salts of hydrochloric acid HCl contain chloride ions and can also be called chlorides. The chloride ion, and its salts such as sodium chloride, are very soluble in water...

.

Uses

Diphenylchlorarsine was first used as a chemical weapon on the Western front during the trench warfare of World War I

World War I

World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...

It belongs to the class of chemicals classified as vomiting agents. Other such agents are diphenylcyanoarsine

Diphenylcyanoarsine

Diphenylcyanoarsine, also called CLARK 2 by the Germans, was discovered in 1918 by Sturniolo and Bellinzoni and shortly thereafter used like the related Clark 1 gas by the Germans for chemical warfare in the First World War. The substance forms colourless, garlic-smelling crystals and causes...

 (DC) and diphenylaminechlorarsine (DM, adamsite).

It is a useful reagent

Reagent

A reagent is a "substance or compound that is added to a system in order to bring about a chemical reaction, or added to see if a reaction occurs." Although the terms reactant and reagent are often used interchangeably, a reactant is less specifically a "substance that is consumed in the course of...

 in the preparation of other diphenylarsenic compounds, e.g. by reactions with Grignard reagents:

RMgBr + (C₆H₅)₂AsCl → (C₆H₅)₂AsR + MgBrCl

Safety

Diphenylchlorarsine is known to cause sneezing, coughing, headache

Headache

A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...

, salivation, and vomiting

Vomiting

Vomiting is the forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose...

. China

China

Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...

 and Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

are negotiating remediation of stocks of a variety of organoarsenic weapons stored in northeastern China including chlorodiphenylarsine.