Tris(triphenylphosphine)chlororhodium
[CAS# 14694-95-2]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic rhodium
• Name: Tris(triphenylphosphine)chlororhodium
• Synonyms: Chlorotris(triphenylphosphine)rhodium(I); Tris(triphenylphosphine)rhodium(I) chloride; Wilkinson's catalyst
• Molecular Formula: C₅₄H₄₅ClP₃Rh
• Molecular Weight: 925.23
• CAS Registry Number: 14694-95-2
• EC Number: 238-744-5
• SMILES: C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=CC=CC=C3.C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=CC=CC=C3.C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=CC=CC=C3.[Cl-].[Rh]

Properties

• Melting point: 245 °C (Expl.)
• Solubility: insoluble (water), soluble (benzene, ethanol, chloroform, dichloromethane)

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H302-H317-H411-H413
• Safety Statements: P261-P264-P270-P272-P273-P280-P301+P317-P302+P352-P321-P330-P333+P317-P362+P364-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Acute toxicity	Acute Tox.	4	H302
Skin sensitization	Skin Sens.	1A	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	2	H411
Skin corrosion	Skin Corr.	1B	H314
Eye irritation	Eye Irrit.	2	H319
Serious eye damage	Eye Dam.	1	H318
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

Tris(triphenylphosphine)chlororhodium is a chemical compound that has found significant applications in the field of organometallic chemistry and catalysis. It is commonly referred to by its molecular formula RhCl(PPh3)3, where Rh stands for rhodium, Cl represents chlorine, and PPh3 is triphenylphosphine. This compound is a coordination complex, where rhodium is the central metal ion surrounded by three triphenylphosphine ligands and one chlorine atom.

The discovery of tris(triphenylphosphine)chlororhodium dates back to the mid-20th century, a period of intense research into transition metal complexes and their catalytic properties. The compound was synthesized as part of efforts to understand the reactivity and stability of rhodium-based complexes. Rhodium, a rare metal, was found to be highly effective in catalyzing various chemical reactions, particularly in processes that involve the activation of carbon-carbon bonds. Its unique ability to stabilize high oxidation states and interact with a variety of ligands makes it an important tool in the synthesis of complex organic molecules.

Tris(triphenylphosphine)chlororhodium has become widely recognized for its catalytic properties, especially in reactions such as hydrogenation, hydroformylation, and carbon-carbon coupling. In particular, it plays a crucial role in the hydrogenation of alkenes, where it helps to reduce double bonds in organic molecules. This process is important in the production of a wide range of chemicals, including pharmaceuticals, agrochemicals, and polymers. Additionally, the compound is used in the hydroformylation of olefins, a process that introduces aldehyde groups into organic molecules, further expanding its utility in the chemical industry.

Another significant application of tris(triphenylphosphine)chlororhodium is in the field of organic synthesis, particularly in reactions that require the formation of carbon-carbon bonds. Its ability to facilitate such reactions makes it a valuable tool for the creation of complex molecules with specific functional groups. The compound’s role as a catalyst in these processes is driven by its ability to coordinate with substrates and activate them, making them more reactive and facilitating the desired chemical transformations.

In addition to its industrial applications, tris(triphenylphosphine)chlororhodium has also been studied for its potential in academic research, particularly in the development of new catalytic systems. Researchers continue to explore ways to optimize its use in various catalytic cycles, as well as to improve its selectivity and efficiency in different reactions.

Despite its widespread use, tris(triphenylphosphine)chlororhodium does have some limitations. It can be sensitive to air and moisture, and as with many transition metal complexes, it requires careful handling and storage. Furthermore, the cost of rhodium, which is a rare and expensive metal, limits the widespread use of this compound in certain applications. Researchers continue to explore ways to reduce the amount of rhodium needed in catalytic processes or to develop more sustainable alternatives.

In conclusion, tris(triphenylphosphine)chlororhodium is an important organometallic compound with diverse applications in catalysis and organic synthesis. Its ability to catalyze a range of reactions has made it invaluable in both industrial and academic settings. While its use is limited by factors such as cost and sensitivity to environmental conditions, ongoing research continues to expand its potential applications and improve its efficiency.

References

2010. [The synthesis of O-substituted 3-oximes of 6alpha-methyl-16alpha,17alpha-cyclohexanopregn-4-ene-3,20-dione tritium-labeled in 1 and 2 positions]. Bioorganicheskaia khimiia, 36, 2.
DOI: 10.1134/s1068162010020172

2008. Infrared Spectroscopy of a Wilkinson Catalyst in a Room-Temperature Ionic Liquid. Chemphyschem : a European journal of chemical physics and physical chemistry, 9, 15.
DOI: 10.1002/cphc.200800450

2002. Intermolecular Transition Metal-Catalyzed [4 + 2 + 2] Cycloaddition Reactions: A New Approach to the Construction of Eight-Membered Rings. Journal of the American Chemical Society, 124, 26.
DOI: 10.1021/ja026351q