(S)-(-)-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl
[CAS# 76189-56-5]

Identification

• Classification: Chemical reagent >> Organic reagent >> Phosphine ligand
• Name: (S)-(-)-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl
• Synonyms: (S)-(-)-BINAP; (S)-BINAP; S-BINAP
• Molecular Formula: C₄₄H₃₂P₂
• Molecular Weight: 622.68
• CAS Registry Number: 76189-56-5
• EC Number: 616-305-2
• SMILES: C1=CC=C(C=C1)P(C2=CC=CC=C2)C3=C(C4=CC=CC=C4C=C3)C5=C(C=CC6=CC=CC=C65)P(C7=CC=CC=C7)C8=CC=CC=C8

Properties

• Melting point: 239-242 °C
• alpha: -240 ° (c=0.3, toluene)

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H315-H319-H335-H410-H413
• Safety Statements: P261-P264-P264+P265-P271-P273-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P391-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Chronic hazardous to the aquatic environment	Aquatic Chronic	4	H413
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Specific target organ toxicity - single exposure	STOT SE	3	H335

Discovery and Applications

(S)-(-)-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl, commonly referred to as (S)-BINAP, is a prominent chiral phosphine ligand with a significant impact on asymmetric catalysis. The ligand's development and application have become pivotal in the synthesis of chiral compounds, with wide-ranging implications in pharmaceuticals and fine chemicals.

The synthesis of (S)-BINAP involves the reaction of 2,2'-dihydroxy-1,1'-binaphthyl with diphenylphosphine. The resulting ligand features a binaphthyl backbone with two diphenylphosphine groups. This configuration provides a rigid, chiral environment around the phosphorus atoms, essential for its role in asymmetric catalysis. The chiral nature of (S)-BINAP arises from the specific spatial arrangement of the binaphthyl moiety, which imparts high enantioselectivity in catalyzed reactions.

The discovery of (S)-BINAP and its application in asymmetric catalysis emerged in the 1980s. Researchers were seeking efficient methods for creating chiral molecules with high enantiomeric purity, and (S)-BINAP proved to be an effective solution. Its development was a breakthrough in the field of asymmetric synthesis, offering a reliable method for achieving high levels of chiral control in various chemical transformations.

One of the primary applications of (S)-BINAP is in asymmetric hydrogenation, a reaction where hydrogen is added to unsaturated compounds to produce chiral products. When used as a ligand in rhodium- or ruthenium-catalyzed hydrogenation processes, (S)-BINAP enables the selective formation of optically active compounds. This has substantial implications in the pharmaceutical industry, where the production of enantiomerically pure drugs is often crucial.

In addition to hydrogenation, (S)-BINAP is extensively used in asymmetric cross-coupling reactions, such as the Suzuki-Miyaura and Negishi coupling reactions. These reactions involve the coupling of organohalides with organometallic reagents to form biaryl compounds. (S)-BINAP, when employed as a ligand in palladium-catalyzed reactions, enhances the selectivity and efficiency of these processes, facilitating the synthesis of complex organic molecules with high chirality.

(S)-BINAP is also utilized in asymmetric hydroamination and other transformations that require precise chiral control. Its versatility and effectiveness in various catalytic processes underscore its importance in the development of new chemical synthesis methods and the production of complex chiral molecules.

The high enantioselectivity achieved with (S)-BINAP is attributed to the ligand's rigid and well-defined chiral environment. The ligand’s ability to stabilize transition metal centers in a specific conformation allows for precise control over the stereochemical outcomes of reactions.

Overall, (S)-(-)-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl has become an indispensable tool in asymmetric catalysis, facilitating the synthesis of chiral compounds across various chemical domains. Its discovery has had a transformative impact on the field, enabling the production of enantiomerically pure substances with high precision.

References

2024. Rh-catalysed enantioselective [2+2+1] cycloaddition reactions using three different 2π-components. Nature Synthesis, 3(7).
DOI: 10.1038/s44160-024-00604-7

2024. Catalytic atroposelective synthesis. Nature Catalysis, 7(4).
DOI: 10.1038/s41929-024-01138-z

1983. Asymmetric Hydrogenation Reactions Using Chiral Diphosphine Complexes of Rhodium. Homogeneous Catalysis with Metal Phosphine Complexes.
DOI: 10.1007/978-1-4613-3623-5_4