4-(Trifluoromethylthio)phenol
[CAS# 461-84-7]

Identification

• Classification: API >> Antipyretic analgesics >> Non-steroidal anti-inflammatory drugs
• Name: 4-(Trifluoromethylthio)phenol
• Synonyms: 4-Trifluoromethylmercaptophenol; 4-Trifluoromethylsulfanylphenol
• Molecular Formula: C₇H₅F₃OS
• Molecular Weight: 194.17
• CAS Registry Number: 461-84-7
• EC Number: 620-583-0
• SMILES: C1=CC(=CC=C1O)SC(F)(F)F

Properties

• Density: 1.5±0.1 g/cm³ Calc.^*
• Melting point: 56 - 57 °C (Expl.)
• Boiling point: 170.4±40.0 °C 760 mmHg (Calc.)^*, 231.5 - 232.9 °C (Expl.)
• Flash point: 56.9±27.3 °C (Calc.)^*
• Index of refraction: 1.529 (Calc.)^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	4	H312
Germ cell mutagenicity	Muta.	2	H341
Acute toxicity	Acute Tox.	4	H332

Discovery and Applications

4-(Trifluoromethylthio)phenol is an aromatic compound characterized by a phenol ring substituted at the para position with a trifluoromethylthio group (-SCF₃). Its molecular formula is C₇H₅F₃OS, reflecting the presence of carbon, hydrogen, fluorine, oxygen, and sulfur atoms. The combination of the phenolic hydroxyl group and the trifluoromethylthio substituent imparts unique chemical and physical properties to the molecule.

The phenol moiety contributes acidity and hydrogen bonding capability, making 4-(trifluoromethylthio)phenol reactive in both electrophilic and nucleophilic aromatic substitution reactions. The -OH group also allows for potential coordination in metal complexes and participation in intermolecular interactions such as hydrogen bonding.

The trifluoromethylthio group is a highly electron-withdrawing and lipophilic substituent due to the presence of electronegative fluorine atoms bonded to sulfur. This group increases the molecule’s overall hydrophobicity and alters its electronic properties, often enhancing metabolic stability and biological activity when incorporated into pharmaceuticals and agrochemicals. The -SCF₃ group is valued in medicinal chemistry for its ability to modulate lipophilicity and membrane permeability of bioactive molecules.

Synthetically, 4-(trifluoromethylthio)phenol can be prepared by nucleophilic aromatic substitution or by the reaction of 4-mercaptophenol with trifluoromethylating agents under controlled conditions. The introduction of the trifluoromethylthio group often involves reagents such as trifluoromethyl iodide, trifluoromethanesulfenyl chloride, or other electrophilic trifluoromethyl sulfur sources.

The compound finds application primarily in the development of pharmaceuticals, agrochemicals, and specialty materials. Incorporation of the trifluoromethylthio substituent into phenolic frameworks has been shown to enhance bioactivity, including antibacterial, antifungal, and anticancer properties, by influencing target binding and metabolic resistance.

Physicochemically, 4-(trifluoromethylthio)phenol is typically a crystalline solid with moderate melting point. It is soluble in organic solvents such as dichloromethane, ethyl acetate, and tetrahydrofuran, but has limited solubility in water due to its hydrophobic trifluoromethylthio group.

In summary, 4-(trifluoromethylthio)phenol is a functionalized aromatic compound featuring a phenol ring and a para-substituted trifluoromethylthio group. Its unique electronic and lipophilic characteristics make it valuable in synthetic chemistry and pharmaceutical development as a building block for bioactive compounds.

References

2018. Visible-Light-Mediated Synthesis of Trifluoromethylthiolated Arenes. Synthesis.
DOI: 10.1055/s-0037-1610322

2018. Trifluoromethylsulfanylation of Phenols. Science of Synthesis.
URL: https://science-of-synthesis.thieme.com/app/text/?id=SD-131-00299

2018. Preparation of Sulfides. Science of Synthesis.
URL: https://science-of-synthesis.thieme.com/app/text/?id=SD-229-00314