Names | |
---|---|
Preferred IUPAC name
Phenylmethanethiol | |
Other names
alpha-Toluenethiol
Benzylthiol Thiobenzyl alcohol Benzyl mercaptan alpha-Toluolthiol Benzylhydrosulfide Benzyl hydrosulfide | |
Identifiers | |
3D model (
JSmol)
|
|
ChEBI | |
ChEMBL | |
ChemSpider | |
ECHA InfoCard | 100.002.602 |
PubChem
CID
|
|
UNII | |
CompTox Dashboard (
EPA)
|
|
| |
| |
Properties | |
C7H8S | |
Molar mass | 124.20 g/mol |
Appearance | colourless liquid |
Odor | Unpleasant leek or garlic-like |
Density | 1.058 g/mL |
Melting point | −30 °C (−22 °F; 243 K) |
Boiling point | 195 °C (383 °F; 468 K) |
low | |
Solubility | very soluble in
ethanol,
ether soluble in CS2 slightly soluble in CCl4 |
Acidity (pKa) | 9.43 (H2O) [1] |
Refractive index (nD)
|
1.5751 (20 °C) |
Hazards | |
NFPA 704 (fire diamond) | |
Flash point | 70 °C (158 °F; 343 K) |
Lethal dose or concentration (LD, LC): | |
LD50 (
median dose)
|
493 mg/kg (rat, oral) |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
|
Benzyl mercaptan is an organosulfur compound with the formula C6H5CH2SH. It is a common laboratory alkylthiol that occurs in trace amounts naturally. It is a colorless, malodorous liquid.
Benzyl mercaptan can be prepared by the reaction of benzyl chloride and thiourea. The initially formed isothiouronium salt must be subjected to alkaline hydrolysis to obtain the thiol.
It has been identified in boxwood (Buxus sempervirens L.) and is known to contribute to the smoky aroma of certain wines. [2] It also occurs naturally in coffee.
Benzyl mercaptan is used for S-alkylation to give benzyl thioethers. [3]
It has been used as a source of the thiol functional group in organic synthesis. Debenzylation can be effected by dissolving metal reduction: [4]
Condensed tannins undergo acid-catalyzed cleavage in the presence of benzyl mercaptan.
Methoxy-substituted benzyl mercaptans have been developed that cleave easily, are recyclable, and are odorless. [5]