Benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium compounds chlorides
[CAS# 61789-72-8]

Identification

• Classification: Pharmaceutical intermediate >> API intermediate
• Name: Benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium compounds chlorides
• CAS Registry Number: 61789-72-8
• EC Number: 263-081-3

Safety Data

• Hazard Symbols: GHS05;GHS07;GHS09 Danger
• Hazard Statements: H302-H315-H318-H400
• Precautionary Statements: P264-P264+P265-P270-P273-P280-P301+P317-P302+P352-P305+P354+P338-P317-P321-P330-P332+P317-P362+P364-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Serious eye damage	Eye Dam.	1	H318
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	4	H302
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Skin corrosion	Skin Corr.	1B	H314
Skin corrosion	Skin Corr.	1C	H314

Discovory and Applicatios

Benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium compounds chlorides belong to the group of cationic surfactants commonly referred to as quaternary ammonium compounds, or quats. Their development arose from the mid-20th century expansion of synthetic surfactant chemistry, which sought compounds with strong antimicrobial activity and functional properties suitable for both household and industrial use. The structure of these compounds is characterized by a quaternary ammonium center bound to two methyl groups, a benzyl substituent, and a long alkyl chain derived from hydrogenated tallow. The counterion is chloride. The hydrogenated tallow alkyl group generally consists of long, saturated hydrocarbon chains, typically C₁₆ to C₁₈, obtained from the hydrogenation of tallow fatty acids to improve oxidative stability and shelf life.

The synthesis of these quaternary ammonium chlorides involves the reaction of a tertiary amine precursor with benzyl chloride. The tertiary amine typically contains the hydrogenated tallow alkyl chain and two methyl groups attached to the nitrogen atom. Quaternization by benzyl chloride results in the introduction of the benzyl substituent and the formation of the positively charged nitrogen center, balanced by a chloride anion. This process was scaled up industrially in the 20th century to meet demand for surface-active agents with enhanced antimicrobial activity compared to earlier surfactants.

Applications of benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium chlorides are extensive due to their amphiphilic nature, which provides both hydrophobic interactions through the long alkyl chain and electrostatic interactions through the quaternary ammonium head group. One of the earliest and most important uses was in disinfectants and sanitizers. Their cationic charge allows them to adsorb strongly to negatively charged microbial cell membranes, disrupting membrane integrity and leading to cell death. This mechanism has made them widely used in hospital disinfectants, household cleaning products, and food industry sanitation practices.

Another major application is in fabric conditioning. These compounds are widely employed in fabric softeners and textile treatments. Their cationic head groups bind effectively to negatively charged textile fibers, while the hydrophobic tails orient outward, creating a lubricating layer that reduces static cling and imparts softness to fabrics. This property has made them an essential component in laundry care formulations since their introduction. Similarly, in hair care products such as conditioners, they provide detangling and conditioning effects by adsorbing onto hair keratin, smoothing the cuticle, and reducing electrostatic buildup.

In industrial and institutional applications, benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium chlorides are used as antistatic agents, emulsifiers, and corrosion inhibitors. Their ability to adsorb onto surfaces and provide a hydrophobic film is valuable in coatings, leather treatment, and other surface modification processes. They are also incorporated into water treatment systems and oilfield chemicals, where they serve as biocides to control microbial growth in pipelines, cooling systems, and other water-handling installations.

The antimicrobial effectiveness of these quaternary ammonium chlorides led to their inclusion as active ingredients in numerous commercial disinfectant formulations. They are recognized for their efficacy against a broad spectrum of bacteria, fungi, and some viruses. Their stability and effectiveness at low concentrations further supported their widespread adoption. However, their persistence in the environment and potential toxicity to aquatic organisms have also been documented, prompting regulatory oversight and evaluation of safe concentration limits in various applications.

The discovery and widespread use of benzyl(hydrogenated tallow alkyl)dimethyl quaternary ammonium compounds chlorides reflect the evolution of surfactant chemistry from basic cleaning agents to multifunctional compounds with antimicrobial, conditioning, and antistatic properties. They remain integral in consumer products, industrial formulations, and disinfection protocols, demonstrating the lasting significance of quaternary ammonium chemistry in modern chemical applications.