Diphenylchlorarsine

Diphenylchlorarsine
Names
IUPAC name
diphenylchloroarsenic, chlorodiphenylarsane, sneezing gas
Other names
diphenylchlorarsine
Identifiers
712-48-1 YesY
3D model (Jmol) Interactive image
Interactive image
Abbreviations Ph2AsCl
ChemSpider 12306 YesY
ECHA InfoCard 100.010.839
PubChem 12836
Properties
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)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
YesY verify (what is YesYN ?)
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.

Preparation and structure

It was first produced in 1878 by Michaelis and La Coste. It is prepared by the reduction of diphenylarsonic acid with sulfur dioxide. An idealized equation is shown:[1]

Ph2AsO2H + SO2 + HCl → Ph2AsCl + H2O + SO3

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.[2]

Uses

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

RMgBr + (C6H5)2AsCl → (C6H5)2AsR + MgBrCl
(R = alkyl, aryl)

Safety

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.[3]

Chemical warfare

Diphenylchlorarsine was used as a chemical weapon on the Western front during the trench warfare of World War I.[4] It belongs to the class of chemicals classified as vomiting agents. Other such agents are diphenylcyanoarsine (DC) and diphenylaminechlorarsine (DM, adamsite).[5] 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.[6]

References

  1. ↑ Blicke, F. F.; Smith, F. D. (1929). "Action of Aromatic Grignard Reagents on Arsenic Trioxide". Journal of the American Chemical Society. 51 (5): 1558–1565. doi:10.1021/ja01380a038.
  2. ↑ Trotter, J. (1962). "Stereochemistry of Arsenic. IV. Chlorodiphenylarsine". Canadian Journal of Chemistry. 40 (8): 1590–1593. doi:10.1139/v62-241.
  3. ↑ "Abandoned Chemical Weapons (ACW) in China". 02/06/2004. Check date values in: |date= (help) Archived July 4, 2008, at the Wayback Machine.
  4. ↑ Gilbert, M. (1995). The First World War—A Complete History. HarperCollins. ISBN 0805047344.
  5. ↑ Holstege, C. P.; Boyle, J. S. (2008-11-26). "CBRNE - Vomiting Agents - Dm, Da, Dc". Medscape.
  6. ↑ Gas and Flame in Modern Warfare, 1918, Chapter IX.
This article is issued from Wikipedia - version of the 11/17/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.