Triphenylphosphine sulfide

Triphenylphosphine sulfide (IUPAC name: triphenyl-λ⁵-phosphanethione) is the organophosphorus compound with the formula (C₆H₅)₃PS, usually written Ph₃PS (where Ph = phenyl). It is a colourless solid, which is soluble in a variety of organic solvents.

Triphenylphosphine sulfide

Names
Preferred IUPAC name Triphenyl-λ5-phosphanethione
Other names Triphenylphosphane sulfide Triphenylphosphine sulfide Triphenylthioxophosphorane
Identifiers
CAS Number	3878-45-3 N
3D model (JSmol)	Interactive image
ChemSpider	18610 Y
ECHA InfoCard	100.021.280
PubChem CID	19758
UNII	Q68E5JRQ8V Y
CompTox Dashboard (EPA)	DTXSID10192046
InChI InChI=1S/C18H15PS/c20-19(16-10-4-1-5-11-16,17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15H Y Key: VYNGFCUGSYEOOZ-UHFFFAOYSA-N Y InChI=1/C18H15PS/c20-19(16-10-4-1-5-11-16,17-12-6-2-7-13-17)18-14-8-3-9-15-18/h1-15H Key: VYNGFCUGSYEOOZ-UHFFFAOYAH
SMILES c1ccc(cc1)P(=S)(c2ccccc2)c3ccccc3
Properties
Chemical formula	(C6H5)3PS
Molar mass	294.350461 g/mol
Appearance	Colourless solid
Melting point	161 to 163 °C (322 to 325 °F; 434 to 436 K)
Solubility	soluble in dichloromethane, ethanol
Related compounds
Related compounds	Triphenylphosphine oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Structurally, the molecule resembles the corresponding oxide, with idealized C₃ point group symmetry.^[1] It is weakly nucleophilic at the sulfur atom.

Applications

Organic synthesis

Triphenylphosphine sulfide is useful for the conversion of epoxides to the corresponding episulfides:^[2]

Ph₂C₂H₂O + Ph₃PS → Ph₂C₂H₂S + Ph₃PO

It also reacts with ketenes to form thioketenes:^[3]

Ph₂CCO + Ph₃PS → Ph₂CCS + Ph₃PO

Analytical chemistry

In analytical chemistry, triphenylphosphine is used for the analysis of certain kinds of sulfur compounds. Elemental sulfur (S₈), as occurs in some oils, and labile organosulfur compounds, such as organic trisulfides, react with triphenylphosphine to give Ph₃PS, which can be detected by gas chromatography.