Butyltriphenylphosphonium bromide
[CAS# 1779-51-7]

Identification

• Classification: Organic raw materials >> Organic phosphine compound
• Name: Butyltriphenylphosphonium bromide
• Synonyms: Butyl(triphenyl)phosphonium bromide; TBP
• Molecular Formula: C₂₂H₂₄P.Br
• Molecular Weight: 399.31
• CAS Registry Number: 1779-51-7
• EC Number: 217-219-4
• SMILES: CCCC[P+](C1=CC=CC=C1)(C2=CC=CC=C2)C3=CC=CC=C3.[Br-]

Properties

• Melting point: 240-243 °C (Expl.)
• Water solubility: soluble

Safety Data

• Hazard Symbols: GHS06;GHS07 Danger
• Risk Statements: H301-H302-H311-H312-H315-H319-H330-H335-H412
• Safety Statements: P260-P261-P262-P264-P264+P265-P270-P271-P273-P280-P284-P301+P316-P301+P317-P302+P352-P304+P340-P305+P351+P338-P316-P317-P319-P320-P321-P330-P332+P317-P337+P317-P361+P364-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
Acute toxicity	Acute Tox.	3	H301
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H311
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Acute toxicity	Acute Tox.	2	H330
Acute toxicity	Acute Tox.	4	H312
Acute toxicity	Acute Tox.	4	H302
Acute toxicity	Acute Tox.	3	H331
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411

Discovery and Applications

Butyltriphenylphosphonium bromide (C6H5)3P(C4H9)Br is a quaternary phosphonium salt that is synthesized by reacting triphenylphosphine with butyl bromide. It consists of a butyl group attached to a triphenylphosphonium cation, with a bromide anion balancing the charge. This compound is a useful reagent in organic chemistry, particularly in reactions where phosphonium salts are involved.

Butyltriphenylphosphonium bromide is widely utilized in synthetic organic chemistry, especially in the preparation of phosphonium ylides. These ylides are highly reactive intermediates that are often employed in reactions such as the Wittig reaction, where they react with carbonyl compounds (like aldehydes or ketones) to form alkenes. The Wittig reaction, an important method for the synthesis of alkenes, relies on the ability of phosphonium ylides to facilitate the formation of carbon-carbon double bonds. Alkenes synthesized through this method are valuable intermediates in the production of pharmaceuticals, agrochemicals, and fine chemicals.

In addition to its role in the Wittig reaction, butyltriphenylphosphonium bromide has been utilized in other synthetic processes involving phosphonium ylides. The compound is also an essential intermediate in the preparation of other phosphonium derivatives that can participate in a variety of chemical transformations. These derivatives have applications in areas such as catalysis, organometallic chemistry, and polymer chemistry.

The reactivity and versatility of butyltriphenylphosphonium bromide make it an important reagent in organic synthesis. Its use extends beyond academic research and into industrial applications, particularly in the manufacture of specialty chemicals and intermediates.

In conclusion, butyltriphenylphosphonium bromide is a valuable and widely used chemical compound in organic chemistry. Its role in the synthesis of phosphonium ylides, and its applications in reactions like the Wittig reaction, make it an essential reagent in the preparation of alkenes and other important chemical intermediates.

References

2023. Efficiency of mitochondrial uncoupling by modified butyltriphenylphosphonium cations and fatty acids correlates with lipophilicity of cations: Protonophoric vs leakage mechanisms. Biochimica et Biophysica Acta (BBA) - Biomembranes, 1865(10).
DOI: 10.1016/j.bbamem.2023.184183

2022. Membrane Permeability of Modified Butyltriphenylphosphonium Cations. The Journal of Physical Chemistry B, 126(1).
DOI: 10.1021/acs.jpcb.1c08135

2023. Novel triphenylphosphonium amphiphilic conjugates of glycerolipid type: synthesis, cytotoxic and antibacterial activity, and targeted cancer cell delivery. RSC Medicinal Chemistry, 14(3).
DOI: 10.1039/D2MD00363E