Tetramethyl ammonium chloride
[CAS# 75-57-0]

Identification

• Classification: Chemical reagent >> Organic reagent >> Amine salt (ammonium salt)
• Name: Tetramethyl ammonium chloride
• Synonyms: Tetramethylammonium chloride; N,N,N-trimethylmethanaminium chloride; TMAC
• Molecular Formula: C₄H₁₂ClN
• Molecular Weight: 109.60
• CAS Registry Number: 75-57-0
• EC Number: 200-880-8
• SMILES: C[N+](C)(C)C.[Cl-]

Properties

• Density: 1.17 g/mL
• Melting point: 425 °C
• Water solubility: >60 g/100 mL (20 °C)

Safety Data

• Hazard Symbols: GHS06;GHS07;GHS08;GHS09 Danger
• Risk Statements: H300-H301-H311-H315-H319-H335-H370-H411
• Safety Statements: P260-P261-P262-P264-P264+P265-P270-P271-P273-P280-P301+P316-P302+P352-P304+P340-P305+P351+P338-P308+P316-P316-P319-P321-P330-P332+P317-P337+P317-P361+P364-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	2	H300
Acute toxicity	Acute Tox.	3	H311
Specific target organ toxicity - single exposure	STOT SE	1	H370
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H301
Acute toxicity	Acute Tox.	4	H312
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410

• Transport Information: UN 2811

Discovery and Applications

Tetramethylammonium chloride (TMAC), with the chemical formula (CH₃)₄NCl, is a quaternary ammonium compound that has garnered significant interest in both chemical research and industrial applications. It is a white, crystalline solid that is highly soluble in water and polar organic solvents. The compound was first synthesized in the early 20th century, with various methods developed to produce it, including the reaction of trimethylamine with methyl chloride.

The discovery of TMAC marked an important advancement in the study of quaternary ammonium compounds, which are characterized by a nitrogen atom bonded to four alkyl groups. This unique structure imparts distinctive properties to TMAC, including its ability to act as a surfactant and its quaternizing ability in organic reactions. The presence of the charged ammonium group allows TMAC to participate in ionic interactions, making it useful in various applications.

One of the primary applications of TMAC is as a phase transfer catalyst. In organic synthesis, TMAC facilitates the transfer of reactants between immiscible phases, thereby enhancing reaction rates and yields. It is particularly useful in reactions involving anionic substrates and nonpolar solvents. By improving the efficiency of chemical reactions, TMAC has become an essential reagent in many synthetic procedures, including those in the pharmaceutical and agrochemical industries.

Additionally, TMAC serves as a reagent in organic synthesis for the preparation of various compounds. Its ability to introduce the tetramethylammonium group into molecules has been utilized in the synthesis of specialty chemicals, including surfactants, polymer additives, and ionic liquids. Furthermore, TMAC is employed in the synthesis of biocides and antiseptics, contributing to the development of antimicrobial agents used in various applications.

In the field of materials science, TMAC is also used in the preparation of ionic liquids, which have gained prominence due to their unique properties, including low volatility and high thermal stability. These ionic liquids have potential applications in electrochemistry, catalysis, and as solvents for chemical reactions, providing a more environmentally friendly alternative to traditional organic solvents.

Despite its wide-ranging applications, the use of TMAC is not without concerns. As with many quaternary ammonium compounds, TMAC has been studied for its potential environmental impact and toxicity. Research has indicated that TMAC can have antimicrobial properties, which may affect non-target organisms in aquatic environments. Consequently, regulatory measures have been considered to manage the use and disposal of TMAC in various industrial processes.

In summary, tetramethylammonium chloride is a versatile quaternary ammonium compound that has found applications in organic synthesis, materials science, and as a phase transfer catalyst. Its unique properties have made it an invaluable tool in chemical research and industry since its discovery in the early 20th century. Ongoing research continues to explore its potential while addressing environmental and safety concerns.

References

2024 In situ techniques for aqueous quinone-mediated electrochemical carbon capture and release. Nature Chemical Engineering, 1, 315.
DOI: 10.1038/s44286-024-00153-y

2024 Insight into the responses of the anammox granular sludge system to tetramethylammonium hydroxide (TMAH) during chip wastewater treatment. Environmental Research, 1, 120099.
DOI: 10.1016/j.envres.2024.120099

2024 An ACE2 PET imaging agent derived from 18F/Cl exchange of MLN-4760 under phase transfer catalysis. EJNMMI Radiopharmacy and Chemistry, 1, 316.
DOI: 10.1186/s41181-024-00316-5