Sulfur tetrachloride

Names
IUPAC name Sulfur(IV) chloride
Identifiers
CAS Number	13451-08-6
3D model (JSmol)	Interactive image
ECHA InfoCard	100.149.178
PubChem CID	13932016
CompTox Dashboard (EPA)	DTXSID20552819
InChI InChI=1/Cl4S/c1-5(2,3)4
SMILES ClS(Cl)(Cl)Cl
Properties
Chemical formula	SCl4
Molar mass	173.87
Appearance	White powder
Melting point	−31 °C (−24 °F; 242 K)
Boiling point	−20 °C (−4 °F; 253 K) (decomposes)
Solubility in water	soluble in water
Hazards
GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H314, H400
Precautionary statements	P260, P264, P273, P280, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P310, P321, P363, P391, P405, P501
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Sulfur tetrachloride is an inorganic compound with chemical formula SCl₄. It has only been obtained as an unstable pale yellow solid. The corresponding SF₄ is a stable, useful reagent.

Preparation and structure

It is obtained by treating sulfur dichloride with chlorine at 193 K:

${\displaystyle {\begin{matrix}{}\\{\ce ((SCl2}+Cl2->[{\text{193 K))]SCl4))\\{}\end{matrix))}$

(1)

It melts with simultaneous decomposition above −20 °C.^[1]

Its solid structure is uncertain. It is probably the salt SCl₃⁺Cl⁻, since related salts are known with noncoordinating anions.^[2][3] In contrast to this tetrachloride, SF₄ is a neutral molecule.^[4]

Reactions

It decomposes above −30 °C (242 K) to sulfur dichloride and chlorine.

${\displaystyle {\begin{matrix}{}\\{\ce {SCl4->[{\text{-15 ))^{\circ }{\ce {C))]{SCl2}+Cl2))\\{}\end{matrix))}$

(2)

It hydrolyzes readily:

${\displaystyle {\ce ((SCl4}+ H2O -> {SOCl2}+ {2HCl))))$

(3)

Sulfur tetrachloride reacts with water, producing hydrogen chloride and sulfur dioxide through the hydrolysis process. Thionyl chloride is an implied intermediate.^[5]

${\displaystyle {\ce ((SCl4}+ 2H2O -> {SO2}+ {4HCl))))$

(4)

• Oxidized by nitric acid:

${\displaystyle {\ce ((SCl4}+ {2HNO3}+ 2H2O -> {H2SO4}+ 2NO2 (^) + {4HCl))))$

(5)