124357-06-8Relevant academic research and scientific papers
P,C-palladacycle complexes of triphenylphosphite: Synthesis, characterization and catalytic activity in the Suzuki cross-coupling reaction
Karami, Kazem,Esfarjani, Shokouh,Abedanzadeh, Sedigheh,Lipkowski, Janusz
, p. 249 - 257 (2014)
Five-membered P,C-palladacycles were synthesized through the reaction of the binuclear triphenylphosphite complex [Pd(μ-Cl)P(OPh)2(OC 6H4)]2 (1) with different monodentate ligands [L = triphenylphosphine (PPh3), thiourea (tu), 2,4,6- trimethylpyridine (Me3Py), pyridine (Py)] and bidentate ligands [N^N = 1,10-phenanthroline (Phen), 4-methyl-1,10-phenanthroline (MePhen)], giving mononuclear P,C-palladacycles [Pd(L)(Cl){P(OPh)2(OC6H 4)}] [L = PPh3 (2a), tu (2b), Me3Py (2c)], [PyH]+[Pd(Cl)2{P(OPh)2(OC6H 4)}]- (3d) and [Pd(N^N){P(OPh)2(OC 6H4)}]+ NO3- [N^N = Phen (4a), MePhen (4b)]. The synthesized complexes were characterized by 1H, 13C-{1H} and 31P-{1H} NMR spectroscopy, elemental analysis and FT-IR techniques. Structural details of complexes 2a, 2c and 3d were determined by X-ray crystallography, which showed these complexes crystallize in the triclinic (2a) and monoclinic (2c and 3d) crystalline systems. According to the structural data, the orthopalladated complex 3c has two different conformers (R,S) in the solid state, although it appeared as one isomer in the solution state, as confirmed by the NMR spectroscopy. Complex 2a, containing PPh3, was evaluated as a homogeneous catalyst for a variety of substrates, affording coupled products in good to excellent yields, importantly at room temperature. Furthermore, the use of the lesser reactive aryl chloride as a substrate in the Suzuki reaction under mild conditions, has received much attention.
Synthesis and NMR spectroscopy of cyclopalladated tertiary phosphite complexes. X-ray crystal structure of Pd(η5-C5H5)(P(OPh)2(OC6H4))
Albinati,Affolter,Pregosin
, p. 379 - 387 (2008/10/08)
The paper reports the authors' initial studies on the cyclometalation and characterization of complexes derived from P(OPh)3 and P(OEt)2(OPh), with the latter ligand selected so that after cyclometalation and subsequent transformation (e.g., carbonylation), hydrolysis would readily yield the ortho-substituted phenol. For comparison purposes the authors have also prepared and cyclopalladated P(OEt)2(NMePh), an N-methylaniline analog. In the course of this work, the crystal structure of Pd(η5-C5H5)(P(OPh)2(OC6H4)) was determined and found to contain some interesting features, which are discussed as well.
