1,1,1-Tris(diphenylphosphinomethyl)ethane
[CAS# 22031-12-5]

Identification

• Classification: Organic raw materials >> Organic phosphine compound
• Name: 1,1,1-Tris(diphenylphosphinomethyl)ethane
• Synonyms: 1,3-Bis(diphenylphosphino)-2-(diphenylphosphino)methyl-2-methylpropane; 2,2-Bis(diphenylphosphinomethyl)-1-(diphenylphosphino)propane; 2-Methyl-2-(diphenylphosphinomethyl)-1,3-bis(diphenylphosphino)propane; Triphos; Tripod
• Molecular Formula: C₄₁H₃₉P₃
• Molecular Weight: 624.67
• CAS Registry Number: 22031-12-5
• EC Number: 811-359-5
• SMILES: CC(CP(C1=CC=CC=C1)C2=CC=CC=C2)(CP(C3=CC=CC=C3)C4=CC=CC=C4)CP(C5=CC=CC=C5)C6=CC=CC=C6

Properties

• Density: 1.19

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

1,1,1-Tris(diphenylphosphinomethyl)ethane, often referred to as triphosphine, is a notable compound in the realm of organophosphorus chemistry, particularly recognized for its role as a ligand in various catalytic processes. This chemical substance is characterized by its three diphenylphosphine groups attached to a central ethane backbone, creating a robust and versatile ligand structure.

The discovery of 1,1,1-Tris(diphenylphosphinomethyl)ethane can be traced to the need for more efficient and selective ligands in transition metal-catalyzed reactions. Its development was driven by the desire to enhance catalytic activity and selectivity in various chemical transformations. The unique structure of this compound, with its three bulky diphenylphosphine groups, provides substantial steric and electronic effects, which are crucial for its function as a ligand.

In catalysis, 1,1,1-Tris(diphenylphosphinomethyl)ethane is employed as a tridentate ligand, which means it can coordinate to a metal center through three points, creating a stable and effective complex. This property is particularly advantageous in catalytic processes that require high stability and reactivity of the metal-ligand complex. The steric bulk of the diphenylphosphine groups helps in stabilizing high oxidation states of transition metals and facilitates various catalytic reactions, including hydrogenation, hydroformylation, and cross-coupling reactions.

One of the key applications of 1,1,1-Tris(diphenylphosphinomethyl)ethane is in the asymmetric hydrogenation of olefins. The presence of the triphosphine ligand significantly improves the enantioselectivity of the hydrogenation process, which is essential for producing chiral products with high purity. This application underscores the importance of this ligand in the pharmaceutical industry, where the synthesis of enantiomerically pure compounds is critical.

Additionally, the compound is used in the hydroformylation of alkenes, a reaction that introduces formyl groups to double bonds, leading to the formation of aldehydes. The efficiency of this reaction is greatly enhanced by the presence of 1,1,1-Tris(diphenylphosphinomethyl)ethane, which stabilizes the transition metal catalyst and facilitates the formation of the desired products. The ligand's ability to stabilize the metal center also extends its use to various cross-coupling reactions, where it improves the reactivity and selectivity of the catalysts.

Beyond its catalytic applications, 1,1,1-Tris(diphenylphosphinomethyl)ethane contributes to the broader understanding of ligand design and coordination chemistry. The study of this compound helps in developing new ligands with enhanced properties and in optimizing catalytic processes for various chemical transformations.

In conclusion, 1,1,1-Tris(diphenylphosphinomethyl)ethane is a significant compound in organophosphorus chemistry, valued for its role as a tridentate ligand in catalytic applications. Its effectiveness in enhancing the selectivity and activity of transition metal catalysts highlights its importance in both industrial and academic settings.

References

1975. Vanadium Compounds. Compounds of Transition Metals.
DOI: 10.1007/978-3-642-50293-4_5

2024. Trans-to-cis isomerization of a platinum(II) complex with two triphosphine ligands via coordination with gold(I) ions. Journal of Inclusion Phenomena and Macrocyclic Chemistry, 104(5-6).
DOI: 10.1007/s10847-024-01228-2

2019. The synthesis of 3,3,3-(Ph2P)3CH-closo-3,1,2-RuC2B9H11, a novel ruthenacarborane complex with a chelate tridentate ligand. Russian Chemical Bulletin, 68(4).
DOI: 10.1007/s11172-019-2484-5