Thionyl chloride

thionyl chloride
IUPAC name: Synonyms: many, see below Formula: SOCl2
Uses:	chlorination reagent
Properties:
Hazards:	toxic
Mass (g/mol): CAS #: 118.97 7719-09-7

Thionyl chloride, SOCl₂, is a pungent toxic chemical widely used as a chlorination reagent in organic chemistry. It has many synonyms, including thionyl dichloride, sulfurous oxychloride, sulfurous dichloride, sulfinyl chloride, sulfinyl dichloride, dichlorosulfoxide, sulfur oxide dichloride, sulfur monoxide dichloride, sulfuryl(IV) chloride. Thionyl chloride itself can be synthesized from sulfur dioxide or sulfur trioxide using other chlorinating reagents including phosgene, phosphorus pentachloride and sulfur dichloride.

As a precursor of mustard gas, it is in the least-controlled Schedule 3 of the Chemical Weapons Convention.