Triphenylphosphine
[CAS# 603-35-0]

Identification

• Classification: Chemical pesticide >> Insecticide intermediate
• Name: Triphenylphosphine
• Synonyms: Triphenyl phosphine
• Molecular Formula: C₁₈H₁₅P
• Molecular Weight: 262.29
• CAS Registry Number: 603-35-0
• EC Number: 210-036-0
• SMILES: C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=CC=CC=C3

Properties

• Density: 1.132
• Melting point: 78.5-81.5 °C
• Boiling point: 377 °C
• Flash point: 181 °C
• Water solubility: Insoluble

Safety Data

• Hazard Symbols: GHS07;GHS08 Danger
• Risk Statements: H302-H317-H350-H412
• Safety Statements: P203-P261-P264-P270-P272-P280-P301+P317-P302+P352-P318-P321-P330-P333+P317-P362+P364-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Skin sensitization	Skin Sens.	1B	H317
Specific target organ toxicity - repeated exposure	STOT RE	1	H372
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Serious eye damage	Eye Dam.	1	H318
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Specific target organ toxicity - single exposure	STOT SE	3	H335
Acute toxicity	Acute Tox.	3	H301
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Acute toxicity	Acute Tox.	4	H332
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Acute toxicity	Acute Tox.	3	H331

Discovery and Applications

Triphenylphosphine, with the chemical formula P(C6H5)3, is an organophosphorus compound that has become a cornerstone in organic chemistry and various industrial applications. Discovered in the mid-19th century, triphenylphosphine was first synthesized by the German chemist Hermann Kolbe in 1850 through the reaction of phosphorus trichloride with phenylmagnesium bromide. Its unique properties, including high stability and strong nucleophilicity, quickly made it a valuable reagent in the burgeoning field of organic synthesis.

One of the most significant applications of triphenylphosphine is as a ligand in coordination chemistry. Due to its ability to form stable complexes with transition metals, it is widely used in the preparation of various metal complexes, which play critical roles in catalysis. For example, triphenylphosphine is a key component in the well-known Wittig reaction, where it facilitates the synthesis of alkenes by reacting with carbonyl compounds to form phosphonium ylides. This reaction has revolutionized synthetic organic chemistry, enabling chemists to construct complex molecular architectures with precision.

In addition to its role as a ligand, triphenylphosphine is also employed as a reducing agent. It can reduce various functional groups, such as nitro groups to amines and aldehydes to alcohols. Its ability to function in mild reaction conditions makes it a preferred choice in many synthetic protocols. Furthermore, triphenylphosphine is utilized in the synthesis of phosphine oxides, which are valuable intermediates in organic synthesis.

Triphenylphosphine's versatility extends to its use in organic photovoltaic materials. Researchers have incorporated triphenylphosphine derivatives into organic solar cells, enhancing their efficiency and stability. The compound's ability to stabilize charge carriers and improve the morphology of active layers has contributed to advancements in the field of renewable energy.

Moreover, triphenylphosphine finds applications in the pharmaceutical industry. It has been used as a precursor for the synthesis of various bioactive compounds, including pharmaceuticals and agrochemicals. Its utility in asymmetric synthesis, where it aids in the formation of chiral centers, has made it invaluable in the production of drugs with specific enantiomeric properties.

Despite its numerous applications, triphenylphosphine is not without its challenges. Its use in large quantities can pose environmental concerns due to its toxicity and potential to bioaccumulate. As such, researchers are exploring greener alternatives and safer methodologies that minimize the use of hazardous reagents while maintaining synthetic efficacy.

In summary, triphenylphosphine is a multifaceted compound with profound implications in organic synthesis, coordination chemistry, renewable energy, and pharmaceuticals. Its discovery has significantly impacted chemical research and industry, showcasing the importance of organophosphorus compounds in contemporary science.

References

1979. Desaturation of eicosa-11,14-dienoic acid in human testes. Lipids.
URL: https://pubmed.ncbi.nlm.nih.gov/459715

2024. A guide for asymmetric synthesis of morphine alkaloids. Medicinal Chemistry Research.
DOI: 10.1007/s00044-024-03350-9

2012. Microwave-Assisted Synthesis of Cyclopentanones Using the Relevant Phosphorus Ylides. Combinatorial Chemistry & High Throughput Screening.
URL: https://pubmed.ncbi.nlm.nih.gov/22263857