Palladium complexes bridging ligands

In contrast, dinuclear, acetato-bridged palladium complexes derived from benzalazine ligands, 26 (m-l), showed Sc (n>7) and N (n = 6-8) phases, although, over much narrower temperature ranges than the chloro-, bromo-and thiocyanato-related complexes [41]. They melt at around 100-130°C and clear at 150 °C. The existence of a mixture of syn/anti isomers is thought to be responsible for the decrease in the transition temperatures, and thus of the liquid-crystalline properties. Interestingly, the mixture is composed of 25% of the syn isomer and 75% of a racemic mixture of the two enantiomers of the anti isomer. An important systematic study has also been carried out. 

The chloro-bridged palladium complex was prepared by reacting the imine ligand with palladium acetate, followed by treatment with HCl, and the other complexes by ion-exchange reactions with KBr, KI, and KSCN. The flat, dinuclear halogeno- and thiocyanato-bridged complexes ((77) M = Pd X = Cl, Br, I, SCN R = CgHia) exhibited a monotropic phase, whereas the acetato-... 

The new arsino(phosphino)methanes with bulky substituents at the two donor centers can behave both as chelating and bridging ligands toward palladium(II). Besides neutral and mono- as well as di-nuclear cationic compounds, in which these ligands are bonded in a chelating fashion, a di-nuclear complex of the A-frame type could also be generated (see Scheme 5).396... 

B(3,5-(CF3)2C6H3)4-.512 Palladium complexes with a hemilabile terdentate carbene ligand, 1,3-bis(pyl)imidazol-2-ylidene, were active toward the catalytic polymerization of CO/norbornylene.513 Palladium complexes of cz s-bidentate C4-bridged diphosphines cis- and trans- 1,2-bis [(diphenylphosphino)methyl]cyclohexane, e fl o,e fl o-2,3-bis[(diphenylphosphino)methyl] norbornane,... 

Pair-of-dimer effects, chromium, 43 287-289 Palladium alkoxides, 26 316 7t-allylic complexes of, 4 114-118 [9JaneS, complexes, 35 27-30 112-16]aneS4 complexes, 35 53-54 [l5]aneS, complexes, 35 59 (l8)aneS4 complexes, 35 66-68 associative ligand substitutions, 34 248 bimetallic tetrazadiene complexes, 30 57 binary carbide not reported, 11 209 bridging triazenide complex, structure, 30 10 carbonyl clusters, 30 133 carboxylates... 

When phenylene- and ethylene-bridged bis(oxazolones) are used as ligands, dinuclear palladium(II) and platinum(ll) 333, 334, and 335 complexes are obtained (Fig. 7.35)." ° In some cases, the close proximity of the ortho phenyl-H-atom to the metal rendered these complexes suitable precursors for ortho metalation. 

Larsen, J., Rasmussen, B.S., Hazell, R.G. and Skrydstrup, T, (2004) Preparation of a novel diphosphine-palladium macrocyclic complex possessing a molecular recognition site. Oxidative addition studies. Chem, Commun., 202-203 Braunstein, P., Clerc, G. and Morise, X. (2003) Cyclopropanation and Diels-Alder reactions catalyzed by the first heterobimetallic complexes with bridging phosphinooxazoline ligands. New J. Chem., 27,68-72 Braunstein, P., Clerc, G., Morise, X., Welter, R. and Mantovani, G. (2003) Phosphinooxazolines as assembling ligands in heterometallic complexes. Dalton Trans., 1601-1605. 

Reactions and Structures of Palladium Complexes Containing Bis(diphenylphosphino)methane as a Bridging Ligand... 

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