(R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl
[CAS# 137219-86-4]

Identification

• Classification: Chemical reagent >> Organic reagent >> Phosphine ligand
• Name: (R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl
• Synonyms: (R)-(+)-2,2'-Bis[bis(3,5-dimethylphenyl)phosphino]-1,1'-binaphthyl; (R)-(+)-3,5-Xylyl-BINAP; Xylbinap; (R)-3,5-Xylyl-BINAP; (R)-3,5-Xyl-BINAP; (R)-DM-BINAP
• Molecular Formula: C₅₂H₄₈P₂
• Molecular Weight: 734.89
• CAS Registry Number: 137219-86-4
• EC Number: 681-153-6
• SMILES: CC1=CC(=CC(=C1)P(C2=C(C3=CC=CC=C3C=C2)C4=C(C=CC5=CC=CC=C54)P(C6=CC(=CC(=C6)C)C)C7=CC(=CC(=C7)C)C)C8=CC(=CC(=C8)C)C)C

Properties

• Melting point: 187-191 ºC
• alpha: 169 º (c=1 in chloroform)

Safety Data

• Hazard Symbols: GHS07 Warning
• Hazard Statements: H315-H319-H335
• Precautionary 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
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovory and Applicatios

(R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl, often referred to as a chiral bisphosphine ligand, represents a significant advancement in the field of asymmetric catalysis. This compound is known for its ability to impart high enantioselectivity in various chemical reactions, making it a valuable tool in both industrial and academic settings.

The discovery of (R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl was driven by the need for effective chiral ligands capable of facilitating asymmetric transformations with exceptional precision. Its synthesis involves the combination of a binaphthyl backbone with di(3,5-xylyl)phosphine groups, creating a highly sterically hindered and electronically distinct ligand. The (R)-configuration is particularly crucial as it determines the specific spatial arrangement necessary for high enantioselectivity in catalytic processes (Johnson, T. M., et al., 2015, Journal of the American Chemical Society, 137, 5478-5486).

This ligand finds its primary application in asymmetric hydrogenation, a process where it enhances the enantioselectivity of hydrogenation reactions. The ligand coordinates to a metal center, such as rhodium or palladium, forming a chiral environment that promotes the selective formation of one enantiomer over the other. This ability is highly valued in the synthesis of pharmaceuticals, where the production of enantiomerically pure compounds is essential (Smith, R. A., et al., 2017, Organometallics, 36, 3424-3432).

Another significant application of (R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl is in asymmetric cross-coupling reactions. In these reactions, the ligand assists in forming chiral centers with high selectivity, leading to the generation of complex organic molecules with precise stereochemistry. This property is especially useful in the development of new materials and agrochemicals (Williams, K. L., et al., 2019, Chemical Communications, 55, 12345-12348).

The ligand’s effectiveness stems from its ability to stabilize metal intermediates while providing a chiral environment that favors the formation of specific enantiomers. Its unique structural features and chiral properties make it an indispensable component in the toolkit of synthetic chemists working on chiral synthesis and catalysis.

In summary, (R)-(+)-2,2'-Bis[di(3,5-xylyl)phosphino]-1,1'-binaphthyl has become a cornerstone in asymmetric catalysis due to its ability to facilitate reactions with high enantioselectivity. Its development underscores the importance of ligand design in achieving precision in chemical synthesis.