1-Hexadecylpyridinium bromide
[CAS# 140-72-7]

Identification

• Classification: Pharmaceutical intermediate >> Heterocyclic compound intermediate >> Pyridine compound >> Chloropyridine
• Name: 1-Hexadecylpyridinium bromide
• Synonyms: Hexadecylpyridine bromide; Hexadecylpyridinium bromide; Cetylpyridinium bromide
• Molecular Formula: C₂₁H₃₈BrN;C₂₁H₃₈N.Br
• Molecular Weight: 384.44
• CAS Registry Number: 140-72-7
• EC Number: 205-428-3
• SMILES: CCCCCCCCCCCCCCCC[N+]1=CC=CC=C1.[Br-]

Properties

• Melting point: 63-69 °C
• Water solubility: 5 g/L (20 °C)

Safety Data

• Hazard Symbols: GHS06;GHS07 Danger
• Risk Statements: H302-H315-H319-H330-H335
• Safety Statements: P260-P261-P264-P264+P265-P270-P271-P273-P280-P284-P301+P317-P302+P352-P304+P340-P305+P351+P338-P316-P319-P320-P321-P330-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	2	H330
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Acute toxicity	Acute Tox.	3	H301
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H413

Discovery and Applications

1-Hexadecylpyridinium bromide, a quaternary ammonium salt, is a compound that has attracted significant attention due to its unique properties and diverse applications. This surfactant features a long hydrophobic alkyl chain, hexadecyl (C16H33), attached to a pyridinium ring, making it amphiphilic in nature. The compound's discovery is rooted in the broader study of surfactants and ionic liquids, which began in the mid-20th century as researchers sought to develop materials with improved surface-active properties and functional versatility.

The synthesis of 1-hexadecylpyridinium bromide involves the alkylation of pyridine with hexadecyl bromide, a process that yields the desired quaternary ammonium salt. The resulting compound exhibits characteristics typical of surfactants, including the ability to reduce surface tension and stabilize emulsions. These properties make it useful in various applications across multiple industries.

One of the primary applications of 1-hexadecylpyridinium bromide is in the formulation of surfactants and emulsifiers. Its amphiphilic nature allows it to effectively stabilize oil-in-water and water-in-oil emulsions, making it valuable in the cosmetic and personal care industries. It is commonly used in lotions, creams, and hair products, where it helps improve the texture and stability of formulations.

In addition to its role in cosmetic formulations, 1-hexadecylpyridinium bromide has been employed in the field of pharmaceuticals. Its surfactant properties can enhance the solubility and bioavailability of poorly soluble drugs, leading to improved therapeutic efficacy. Researchers have explored its potential in drug delivery systems, particularly in the formulation of nanoparticles and liposomes, where it can facilitate the encapsulation and release of active pharmaceutical ingredients.

The compound also finds applications in material science and nanotechnology. 1-Hexadecylpyridinium bromide is used as a template agent in the synthesis of mesoporous materials, which have numerous applications in catalysis and adsorption. Its ability to form organized structures at the molecular level enables the development of materials with specific pore sizes and surface characteristics, which can be tailored for particular uses.

Furthermore, 1-hexadecylpyridinium bromide has shown promise in environmental applications, particularly in the field of wastewater treatment. Its surfactant properties can aid in the removal of contaminants from water, making it a potential candidate for use in remediation processes.

Despite its versatility, caution should be exercised when handling 1-hexadecylpyridinium bromide due to its potential toxicity and environmental impact. Appropriate safety measures should be implemented to minimize exposure during its use and application.

In summary, 1-hexadecylpyridinium bromide is a significant compound within the class of quaternary ammonium salts, recognized for its surfactant properties and broad range of applications. Its contributions to the cosmetic, pharmaceutical, and material science industries highlight its importance in the development of innovative products and processes. Ongoing research continues to explore new applications and enhancements of this compound, contributing to advancements in various fields.

References

2024. Enhanced Cr(VI) removal via CPBr-modified MIL-88A@amine-functionalized GO: synthesis, performance, and mechanism. Environmental science and pollution research international. Eman N. Hammad, Abdelazeem S. Eltaweil, Saeyda A. Abouelenein, Gehan El-Subruiti.
DOI: 10.1007/s11356-024-33859-w

2024. Water Contamination and Impacts of Synthetic Microfibers Pollutants to the Global Ecosystem. Sustainable Microbial Technology for Synthetic and Cellulosic Microfiber Bioremediation. Mittali Tyagi.
DOI: 10.1007/978-3-031-62600-5_9

2024. The Effect of a Magnetic Field on the Generation of Free Radicals in the Interaction of Quaternary Ammonium Compounds with Hydroperoxides. Russian Journal of Physical Chemistry B. D. A. Krugovov, A. K. Gatin, N. V. Potapova, V. G. Kondratovich, E. A. Mengele, O. T. Kasaikina.
DOI: 10.1134/s199079312470012x