Tetrabutylphosphonium bromide
[CAS# 3115-68-2]

Identification

• Classification: Organic raw materials >> Organic phosphine compound
• Name: Tetrabutylphosphonium bromide
• Molecular Formula: C₁₆H₃₆P.Br
• Molecular Weight: 339.34
• CAS Registry Number: 3115-68-2
• EC Number: 221-487-8
• SMILES: CCCC[P+](CCCC)(CCCC)CCCC.[Br-]

Properties

• Melting point: 99-104 °C
• Flash point: 290 °C
• Water solubility: ca 70 g/100 mL

Safety Data

• Hazard Symbols: GHS05;GHS06;GHS07;GHS08;GHS09 Danger
• Risk Statements: H302-H311-H315-H317-H318-H335-H361fd-H411
• Safety Statements: P203-P261-P262-P264-P264+P265-P270-P271-P272-P273-P280-P301+P317-P302+P352-P304+P340-P305+P354+P338-P316-P317-P318-P319-P321-P330-P332+P317-P333+P317-P361+P364-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Serious eye damage	Eye Dam.	1	H318
Acute toxicity	Acute Tox.	3	H311
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin sensitization	Skin Sens.	1B	H317
Reproductive toxicity	Repr.	2	H361fd
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	2	H310
Eye irritation	Eye Irrit.	2	H319
Substances or mixtures corrosive to metals	Met. Corr.	1	H290
Reproductive toxicity	Repr.	2	H361
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H332
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413

• Transport Information: UN 3464

Discovery and Applications

Tetrabutylphosphonium bromide, often abbreviated as TBPB, is an organic compound with the chemical formula C16H36BrP. This salt is formed from tetrabutylphosphonium cations and bromide anions. It was first synthesized in the mid-20th century as part of a broader effort to explore quaternary ammonium and phosphonium salts for various applications, particularly in organic synthesis and catalysis.

The synthesis of tetrabutylphosphonium bromide typically involves the reaction of tetrabutylphosphonium hydroxide with hydrobromic acid or a bromide salt. This compound is highly soluble in polar organic solvents, which facilitates its use in various chemical reactions. The unique properties of TBPB make it an effective phase transfer catalyst, enabling the transfer of anionic species between aqueous and organic phases. This characteristic is particularly valuable in organic synthesis, where it aids in improving reaction rates and yields.

One of the prominent applications of tetrabutylphosphonium bromide is in the field of organic synthesis. It is commonly employed in nucleophilic substitution reactions and has been utilized in the synthesis of various organic compounds, including pharmaceuticals and agrochemicals. TBPB facilitates the reaction of otherwise poorly soluble reactants, making it a useful reagent in multistep syntheses.

Additionally, TBPB has found applications in the extraction of metal ions, particularly in the field of analytical chemistry. Its ability to form stable complexes with various metal ions allows for the effective separation and determination of these ions in complex matrices. This property has been exploited in the development of analytical methods for environmental monitoring, where the detection of heavy metals is essential.

In the context of materials science, tetrabutylphosphonium bromide has been investigated for its potential use in polymer chemistry. It can serve as a plasticizer or additive in the formulation of polymeric materials, influencing their mechanical properties and processing behavior. Researchers have explored its role in the synthesis of polymeric composites that exhibit improved thermal and mechanical properties.

Furthermore, TBPB has been studied for its potential applications in the field of ionic liquids. Its unique solubility characteristics and thermal stability make it a candidate for developing new ionic liquid formulations, which have gained interest for their green chemistry attributes. Ionic liquids are known for their low volatility, non-flammability, and ability to dissolve a wide range of substances, making them suitable for various industrial applications.

In summary, tetrabutylphosphonium bromide is a versatile compound with a rich history of discovery and a wide range of applications in organic synthesis, analytical chemistry, materials science, and ionic liquid research. Its ability to facilitate chemical reactions and extract metal ions makes it an invaluable tool in both academic research and industrial applications. Continued exploration of TBPB's properties and potential uses may lead to further innovations in diverse fields.

References

2022. Intermolecular Interaction of Tetrabutylammonium and Tetrabutylphosphonium Salt Hydrates by Low-Frequency Raman Observation. Molecules (Basel, Switzerland), 27(15).
DOI: 10.3390/molecules27154743

2021. Enzymatic Activity and Its Relationship with Organic Matter Characterization and Ecotoxicity to Aliivibrio fischeri of Soil Samples Exposed to Tetrabutylphosphonium Bromide. Sensors (Basel, Switzerland), 21(5).
DOI: 10.3390/s21051565

2015. Facile, room-temperature pre-treatment of rice husks with tetrabutylphosphonium hydroxide: Enhanced enzymatic and acid hydrolysis yields. Bioresource Technology, 197.
DOI: 10.1016/j.biortech.2015.08.056