(R)-1-[(1R)-1-[Bis(3,5-dimethylphenyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene
[CAS# 184095-69-0]

Identification

• Classification: Chemical reagent >> Organic reagent >> Phosphine ligand
• Name: (R)-1-[(1R)-1-[Bis(3,5-dimethylphenyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene
• Synonyms: (R)-1-[(Sp-2(Diphenylphosphino)ferrocenyl]ethyldi(3,5-xylyl)phosphine
• Molecular Formula: C₄₀H₄₀FeP₂
• Molecular Weight: 638.54
• CAS Registry Number: 184095-69-0
• EC Number: 809-919-9
• SMILES: Cc1cc(cc(c1)P(c2cc(cc(c2)C)C)[C@@H](C)[C]3[CH][CH][CH][C]3P(c4ccccc4)c5ccccc5)C.[CH]1[CH][CH][CH][CH]1.[Fe]

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H302-H315-H319-H335
• Safety Statements: P261-P305+P351+P338

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413

Discovery and Applications

(R)-1-[(1R)-1-[Bis(3,5-dimethylphenyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene, known for its role in asymmetric catalysis, is a member of the class of ferrocenyl phosphine ligands. These ligands are known for their ability to control the stereochemical outcomes of various reactions due to their unique structure, which combines a ferrocene backbone with two distinct phosphine groups. The compound's development reflects ongoing research into efficient chiral ligands for transition metal-catalyzed processes, particularly in asymmetric hydrogenation and cross-coupling reactions.

The discovery of this compound stemmed from extensive work on chiral ferrocenyl ligands in the late 1990s and early 2000s. Researchers sought to improve the stereoselectivity of transition metal catalysis by designing ligands that feature rigid, sterically demanding, and electronically tunable phosphine groups. The inclusion of bis(3,5-dimethylphenyl)phosphine on one arm and diphenylphosphine on the other allows the ligand to provide differentiated electronic and steric environments. This dual functionality enhances the ligand's ability to promote enantioselective transformations with high efficiency.

The synthesis of (R)-1-[(1R)-1-[Bis(3,5-dimethylphenyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene typically involves several steps. The starting point is often a ferrocene derivative that undergoes functionalization to introduce the phosphine groups asymmetrically. The chiral center in the ethyl backbone is introduced through stereoselective synthesis techniques, ensuring the ligand's configuration is maintained. These ligands are then coordinated to metals such as rhodium, palladium, or ruthenium to create highly effective chiral catalysts.

This compound finds significant applications in asymmetric catalysis, particularly in hydrogenation reactions. When coordinated with rhodium, it facilitates the hydrogenation of prochiral alkenes, imines, and ketones with excellent enantioselectivity. This makes it valuable in the pharmaceutical industry, where producing enantiomerically pure compounds is essential for drug development. Additionally, the ligand has been employed in asymmetric C-C bond-forming reactions, including Suzuki-Miyaura couplings and allylic substitutions, where control of stereochemistry is critical.

The effectiveness of (R)-1-[(1R)-1-[Bis(3,5-dimethylphenyl)phosphino]ethyl]-2-(diphenylphosphino)ferrocene lies in its ability to create a chiral environment around the metal center, thereby influencing the approach of substrates during catalysis. This capability has led to its widespread use in the synthesis of fine chemicals, agrochemicals, and active pharmaceutical ingredients. Continued research into ferrocenyl phosphine ligands is expected to expand their utility further, offering new possibilities in asymmetric synthesis and green chemistry.

References

none