• Source: Bis(triphenylphosphine)palladium chloride

Bis(triphenylphosphine)palladium chloride is a coordination compound of palladium containing two triphenylphosphine and two chloride ligands. It is a yellow solid that is soluble in some organic solvents. It is used for palladium-catalyzed coupling reactions, e.g. the Sonogashira–Hagihara reaction. The complex is square planar. Many analogous complexes are known with different phosphine ligands.




Preparation and reactions


This compound may be prepared by treating palladium(II) chloride with triphenylphosphine:

PdCl2 + 2 PPh3 → PdCl2(PPh3)2
Upon reduction with hydrazine in the presence of excess triphenylphosphine, the complex is a precursor to tetrakis(triphenylphosphine)palladium, Pd(PPh3)4:

2 PdCl2(PPh3)2 + 4 PPh3 + 5 N2H4 → 2 Pd(PPh3)4 + N2 + 4 N2H5+Cl−




Structure


Several crystal structures containing PdCl2(PPh3)2 have been reported. In all of the structures, PdCl2(PPh3)2 adopts a square planar coordination geometry and the trans isomeric form.




Applications


The complex is used as a pre-catalyst for a variety of coupling reactions.


The Suzuki reaction was once limited by high levels of catalyst and the limited availability of boronic acids. Replacements for halides were also found, increasing the number of coupling partners for the halide or pseudohalide as well. Using bis(triphenylphosphine)palladium chloride as the catalyst, triflates and boronic acids have been coupled on an 80 kilogram scale in good yield. The same catalyst is effective for the Sonogashira coupling.




See also


Bis(triphenylphosphine)platinum(II) chloride
Bis(triphenylphosphine)nickel(II) chloride




References

Kata Kunci Pencarian:

• Paladium
• Bilangan oksidasi
• Bis(triphenylphosphine)palladium chloride
• Bis(triphenylphosphine)platinum chloride
• Palladium(II) chloride
• Triphenylphosphine
• Palladium compounds
• Palladium
• Dichlorobis(triphenylphosphine)nickel(II)
• Acyl chloride
• Negishi coupling
• Metal halides