Tetradecyldimethylbenzylammonium chloride
[CAS# 139-08-2]

Identification

• Classification: API >> Synthetic anti-infective drugs >> Disinfectant antiseptic
• Name: Tetradecyldimethylbenzylammonium chloride
• Synonyms: Benzyldimethyltetradecylammonium chloride
• Molecular Formula: C₂₃H₄₂N.Cl
• Molecular Weight: 368.04
• CAS Registry Number: 139-08-2
• EC Number: 205-352-0
• SMILES: CCCCCCCCCCCCCC[N+](C)(C)CC1=CC=CC=C1.[Cl-]

Properties

• Melting point: 56-62 °C

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS09 Danger
• Risk Statements: H302-H312-H314-H318-H400-H410
• Safety Statements: P260-P264-P264+P265-P270-P273-P280-P301+P317-P301+P330+P331-P302+P352-P302+P361+P354-P304+P340-P305+P354+P338-P316-P317-P321-P330-P362+P364-P363-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Skin corrosion	Skin Corr.	1B	H314
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	4	H312
Serious eye damage	Eye Dam.	1	H318
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H332
Skin corrosion	Skin Corr.	1A	H314
Acute toxicity	Acute Tox.	2	H330
Acute toxicity	Acute Tox.	3	H301
Skin sensitization	Skin Sens.	1	H317
Acute toxicity	Acute Tox.	3	H311
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin corrosion	Skin Corr.	1	H314
Skin corrosion	Skin Corr.	1C	H314
Specific target organ toxicity - repeated exposure	STOT RE	2	H373

• Transport Information: UN 3261

Discovery and Applications

Tetradecyldimethylbenzylammonium chloride is a quaternary ammonium compound, often classified as a cationic surfactant and disinfectant. Structurally, it consists of a quaternary nitrogen atom bonded to a tetradecyl (C₁₄) alkyl chain, two methyl groups, and a benzyl group, with chloride as the counterion. The combination of a long hydrophobic alkyl chain and a positively charged nitrogen center provides both surface-active and antimicrobial properties. Compounds of this type were first developed in the mid-20th century to address the need for effective disinfectants and sanitizers with broad-spectrum activity and improved stability over earlier ammonium compounds.

The antimicrobial activity of tetradecyldimethylbenzylammonium chloride arises from its ability to interact with negatively charged microbial cell membranes, disrupting membrane integrity and causing leakage of cellular contents. This mechanism makes it effective against a range of bacteria, including Gram-positive and Gram-negative strains, as well as certain fungi. It is widely used in industrial and household disinfectants, surface sanitizers, and cleaning products where rapid microbial control is required.

In addition to its biocidal applications, this compound functions as a cationic surfactant in personal care formulations. It is incorporated into hair conditioners, shampoos, and skin creams to improve conditioning, reduce static, and enhance smoothness. The positively charged head group adheres to negatively charged surfaces such as hair and skin, while the hydrophobic tail improves lubrication and spreadability. In textile and fabric care, tetradecyldimethylbenzylammonium chloride is used in fabric softeners, antistatic treatments, and textile finishing, where it binds to fibers, enhancing softness and reducing static electricity.

The compound also finds applications as an emulsifying agent in chemical formulations. Its amphiphilic structure allows it to stabilize oil-in-water emulsions, improving the consistency and shelf-life of various products. Industrially, it is used in water treatment, pulp and paper processing, and other processes where cationic surfactants can facilitate dispersion, flocculation, or surface modification.

Environmental and safety considerations are important in the use of tetradecyldimethylbenzylammonium chloride. Like other quaternary ammonium compounds, it is toxic to aquatic organisms and may accumulate in the environment if wastewater is not treated appropriately. Proper handling protocols, including protective equipment and controlled usage concentrations, are necessary to mitigate exposure risks to humans and the environment.

The development of tetradecyldimethylbenzylammonium chloride reflects the broader trend in surfactant chemistry to design multifunctional molecules that combine antimicrobial efficacy, conditioning, and emulsifying properties. Its enduring use in personal care, household, and industrial products demonstrates the effectiveness of quaternary ammonium chemistry in providing practical solutions for sanitation, material conditioning, and formulation stability. The compound’s versatility and robust performance continue to make it a valuable component in modern chemical and consumer products.

References

2023. Determination of 25 quaternary ammonium compounds in sludge by liquid chromatography–mass spectrometry. Analytical Sciences, 39(5).
DOI: 10.1007/s44211-023-00354-0

2021. Grapefruit Seed Extract as a Natural Food Antimicrobial: a Review. Food and Bioprocess Technology, 14(4).
DOI: 10.1007/s11947-021-02610-5

2022. Synthesis of Gold Nanorods in a Binary Mixture of Cationic Surfactants. Colloid Journal, 84(1).
DOI: 10.1134/s1061933x22010136