Diphenylchloroarsine

Diphenylchlorarsine

Names
IUPAC name diphenylchloroarsenic, chlorodiphenylarsane, sneezing gas
Other names diphenylchlorarsine
Identifiers
CAS Number	712-48-1 Y
3D model (Jmol)	Interactive image Interactive image
Abbreviations	Ph2AsCl
ChemSpider	12306 Y
ECHA InfoCard	100.010.839
PubChem	12836
InChI InChI=1S/C12H10AsCl/c14-13(11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10H Y Key: YHHKGKCOLGRKKB-UHFFFAOYSA-N Y InChI=1/C12H10AsCl/c14-13(11-7-3-1-4-8-11)12-9-5-2-6-10-12/h1-10H Key: YHHKGKCOLGRKKB-UHFFFAOYAA
SMILES Cl[As](C1=CC=CC=C1)C2=CC=CC=C2 Cl[As](c1ccccc1)c2ccccc2
Properties
Chemical formula	C12H10AsCl
Molar mass	264.59 g mol−1
Appearance	colorless crystalline solid
Density	1.55 g/cm3
Melting point	42 °C (108 °F; 315 K)
Magnetic susceptibility (χ)	-145.5·10−6 cm3/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

Diphenylchloroarsine (DA) is the organoarsenic compound with the formula (C₆H₅)₂AsCl. It is highly toxic and was once used in chemical warfare. It is also an intermediate in the preparation of other organoarsenic compounds. The molecule consists of a pyramidal As(III) center attached to two phenyl rings and one chloride.

It was first produced in 1878 by Michaelis and La Coste. It is prepared by the reduction of diphenylarsinic acid with sulfur dioxide. An idealized equation is shown:

The structure consists of pyramidal As centre. The As-Cl distance is 2.26 A and the Cl-As-C and C-As-C angles are 96 and 105°, respectively.

It is a useful reagent for the preparation of other diphenylarsenic compounds, e.g. by reactions with Grignard reagents:

Diphenylchlorarsine was used as a chemical weapon on the Western front during the trench warfare of World War I. It belongs to the class of chemicals classified as vomiting agents. Other such agents are diphenylcyanoarsine (DC) and diphenylaminechlorarsine (DM, adamsite). Diphenylchlorarsine was sometimes believed to penetrate the gas masks of the time and to cause violent sneezing, forcing removal of the protecting device. The Germans called it "Maskenbrecher", "mask breaker", together with other substances with similar effect: Adamsite, diphenylarsincyanide, diphenylaminarsincyanide. Fortunately, this gas did not actually penetrate masks any better than other gases.

Diphenylchlorarsine is known to cause sneezing, coughing, headache, salivation, and vomiting. China and Japan are negotiating remediation of stocks of a variety of organoarsenic weapons dumped in northeastern China after Japan's numerous invasions of China, including chlorodiphenylarsine.