[1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II)
[CAS# 67292-34-6]

Identification

• Classification: Organic raw materials >> Organometallic compound >> Organic nickel
• Name: [1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II)
• Molecular Formula: C₃₄H₂₈Cl₂FeNiP₂
• Molecular Weight: 683.98
• CAS Registry Number: 67292-34-6
• EC Number: 625-604-7
• SMILES: c1ccc(cc1)P(c2ccccc2)[C]3[CH][CH][CH][CH]3.c1ccc(cc1)P(c2ccccc2)[C]3[CH][CH][CH][CH]3.Cl[Ni]Cl.[Fe]

Properties

• Melting point: 285 ºC (dec.)

Safety Data

• Hazard Symbols: GHS07;GHS08 Danger
• Hazard Statements: H372-H317-H334-H350
• Precautionary Statements: P501-P272-P260-P270-P202-P201-P264-P280-P284-P302+P352-P308+P313-P362+P364-P304+P340-P333+P313-P405

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin sensitization	Skin Sens.	1	H317
Respiratory sensitization	Resp. Sens.	1	H334
Carcinogenicity	Carc.	1B	H350
Carcinogenicity	Carc.	1A	H350

Discovory and Applicatios

[1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II), commonly referred to as Ni(dppf)Cl₂, is a well-known organometallic complex widely used in various catalytic applications, particularly in cross-coupling reactions. The complex consists of a nickel(II) ion coordinated by two chlorine atoms and a bidentate ligand, 1,1'-bis(diphenylphosphino)ferrocene (dppf), which is a ferrocene derivative with two diphenylphosphino groups attached to the cyclopentadienyl rings. This coordination structure provides Ni(dppf)Cl₂ with both stability and reactivity, making it a valuable catalyst in organic synthesis.

The discovery of [1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II) was driven by the search for efficient nickel-based catalysts that could facilitate various organic transformations under mild conditions. The synthesis of this complex involves the reaction of nickel(II) chloride with 1,1'-bis(diphenylphosphino)ferrocene in a suitable solvent, such as dichloromethane or toluene. The resulting complex exhibits a square-planar geometry around the nickel center, with the dppf ligand providing two phosphorus atoms for coordination, which stabilizes the metal center and enhances its catalytic properties.

One of the most significant applications of Ni(dppf)Cl₂ is in the field of cross-coupling reactions, particularly the Suzuki-Miyaura and Kumada-Tamao-Corriu couplings. In the Suzuki-Miyaura reaction, the complex acts as a catalyst for the formation of carbon-carbon bonds between aryl halides and boronic acids. The robust nature of the dppf ligand in this complex ensures the stabilization of nickel intermediates during the catalytic cycle, which is crucial for the efficient formation of biaryl products. The Kumada-Tamao-Corriu coupling, on the other hand, involves the reaction of aryl halides with Grignard reagents, where Ni(dppf)Cl₂ again serves as an effective catalyst, promoting the formation of carbon-carbon bonds under relatively mild conditions.

Beyond cross-coupling reactions, Ni(dppf)Cl₂ has also found use in other catalytic processes, such as the hydroamination of alkenes and the reductive coupling of aldehydes. In hydroamination, the complex catalyzes the addition of amines to alkenes, forming C-N bonds in a regioselective manner. This reaction is particularly important in the synthesis of amines, which are valuable intermediates in pharmaceuticals and agrochemicals. The reductive coupling of aldehydes, catalyzed by Ni(dppf)Cl₂, leads to the formation of 1,2-diols, which are useful building blocks in organic synthesis.

The application of Ni(dppf)Cl₂ extends to the polymerization of olefins, where it acts as a catalyst in the formation of high molecular weight polymers. The presence of the dppf ligand in the nickel complex allows for controlled polymerization, leading to polymers with defined molecular weights and structures. This capability is particularly important in the production of materials with specific properties, such as high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE).

In addition to its role in catalysis, [1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II) has been studied for its electrochemical properties, owing to the presence of the ferrocene moiety in the ligand. Ferrocene is well-known for its reversible redox behavior, and the incorporation of this functionality into the nickel complex allows for the exploration of its redox properties in various applications, including in the development of sensors and redox-active materials.

The versatility of Ni(dppf)Cl₂ in catalysis and its unique electrochemical properties have made it a compound of significant interest in both academic research and industrial applications. Its ability to promote a wide range of chemical transformations under mild conditions, combined with the stability provided by the dppf ligand, ensures that Ni(dppf)Cl₂ will continue to be a valuable tool in synthetic chemistry. As research into nickel-catalyzed processes continues, the applications of [1,1'-Bis(diphenylphosphino)ferrocene]dichloronickel(II) are likely to expand, further solidifying its role in the development of new catalytic methodologies.