Sesquimustard (military code Q) is the organosulfur compound with the formula (ClCH2CH2SCH2)2. Although it is a colorless solid, impure samples are often brown. The compound is a type of mustard gas, a vesicant used as a chemical weapon. From the chemical perspective, the compound is both a thioether and an alkyl chloride.
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| Names | |
|---|---|
| Preferred IUPAC name 1,2-Bis[(2-chloroethyl)sulfanyl]ethane | |
| Other names Agent Q TL-86 One-and-one-half mustard | |
| Identifiers | |
3D model (JSmol) | |
| ChemSpider | |
PubChem CID | |
| UNII | |
CompTox Dashboard (EPA) | |
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| Properties | |
| C6H12Cl2S2 | |
| Molar mass | 219.18 g·mol−1 |
| Appearance | white solid (impure samples: pale brown) |
| Melting point | 56.5 °C (133.7 °F; 329.6 K) |
| Insoluble, slowly degrades | |
| Solubility | Alcohols, hydrocarbons, lipids, ethers, THF |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Because sesquimustard is a solid at room temperature, it is not as easily deployed as related liquid mustards. It was only ever deployed as mixtures with the original mustard, with phosgene, or as a solution. Since 1997, it has been listed under Schedule I of the Chemical Weapons Convention, as a substance with few uses outside of chemical warfare[1][2][3] (although since then, it has been found to be useful in chemotherapy).[4]