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Triphenylphosphine (IUPAC name: triphenylphosphane) is a common organophosphorus compound with the formula P(C 6 H 5) 3 and often abbreviated to P Ph 3 or Ph 3 P. It is versatile compound that is widely used as a reagent in organic synthesis and as a ligand for transition metal complexes, including ones that serve as catalysts in organometallic chemistry.
Trifluorophosphine (PF 3) is a strong π-acid with bonding properties akin to those of the carbonyl ligand. [8] In early work, phosphine ligands were thought to utilize 3 d orbitals to form M-P pi-bonding, but it is now accepted that d-orbitals on phosphorus are not involved in bonding. [ 9 ]
Triphenylphosphite is a notable example of polyamorphism in organic compounds, namely it exists in two different amorphous forms at temperatures about 200 K. [5] One polymorphic modification of triphenyl phosphite was obtained by means of crystallization in ionic liquids. [6]
Wilkinson's catalyst is usually obtained by treating rhodium(III) chloride hydrate with an excess of triphenylphosphine in refluxing ethanol. [9] [10] [1] Triphenylphosphine serves as both a ligand and a two-electron reducing agent that oxidizes itself from oxidation state (III) to (V).
By changing the ligand to, e.g., P(O-iPr) 3 the selectivity can be improved significantly. [8] In addition, Lipshutz et al., have shown that the addition of a bidentate, achiral bis-phosphine ligand on the Cu center can lead to substrate-to-ligand ratios typically on the order of 1000−10000:1 can be used to afford products in high yields.
The four phosphorus atoms are at the corners of a tetrahedron surrounding the palladium(0) center. This structure is typical for four-coordinate 18 e − complexes. [2] The corresponding complexes Ni(PPh 3) 4 and Pt(PPh 3) 4 are also well known.
Ligands may bridge two or more centres. The prefix μ is used to specify a bridging ligand in both the formula and the name. For example the dimeric form of aluminium trichloride: Al 2 Cl 4 (μ-Cl) 2 di-μ-chlorido-tetrachlorido-1κ 2 Cl,2κ 2 Cl-dialuminium. This example illustrates the ordering of bridging and non bridging ligands of the same ...
In coordination chemistry, the ligand cone angle (θ) is a measure of the steric bulk of a ligand in a transition metal coordination complex. It is defined as the solid angle formed with the metal at the vertex of a cone and the outermost edge of the van der Waals spheres of the ligand atoms at the perimeter of the base of the cone.