Pyridine type ligands

Here, eM, Ml, and / Ml2 are the respective extinction coefficients of all participants of Eq. (1) and [Mb is the total concentration of 1. The values of Kl and K2]j are summarized in Table II. The solid line in the inset was calculated using the best-fit values of mt / Ml2, A l, and K2h, while the broken line is the calculated prediction if K2l 0. The broken line deviates systematically from the experimental points confirming the binding of the second pyridine-type ligand. Imidazole behaves similarly (27). 

Pyridine-type ligands (g) Heterocyclic nitrogen ligands ... 

As for N-heterocyclic type ligands, four species namely pyridine type ligands, imidazole type ligands, porphyrin type ligands, and phthalocyanine type ligands were involved. The synthesis and structure characteristics of this type of complexes will be detailed below ... 

Rare Earth Complexes with Pyridine Type Ligands... 

Figure 4.11 Eight representative pyridine type ligands.

Catenane synthesis can be also achieved by dynamic molecular association. Figure 3.27 shows an example of catenane preparation through the dynamic formation of a palladium (Pd) complex. Mixing the Pd complex with pyridine-type ligands in water induces the formation of both a monocyclic structure and an interlocked catenane. An equilibrium exists between these two structures, and the catenane structures are more favorable at higher concentrations. In the catenane structure, the benzene rings stack next to each other due to favorable... 

Similar studies have been made to determine the acid-strengthening effect of a metal ion on the p-hydroxy group attached to a pyridine-type ligand (5, 5). The ligands used in this study were 2,6-dicarboxy-4-... 

Similar to semicorrin ligands, chiral bis(4,5-dihydro-2-oxazolyl) systems 3 are used in copper-catalyzed asymmetric cyclopropanation of styrene with diazoacetates57 61, 9 ". In a similar way. bis(oxazolinyl)pyridine type ligands have also been used100. 

So, NMR spectra of 4,4 -bipyridyl, pyrazine, and ethylenediamine coordinated to undecatungstocobalto(III)silicate and -borate anions. Identification of 1 1 and dumbbell-shaped 12 complexes, Bull. Korean Chem. Soc, 14 759 (1993) (c) J.L. Samonte and M.T. Pope, Derivatization of polyoxotungstates in aqueous solution. Exploration of the kinetic stability ofcobalt(II)- and cobalt(III) derivatives of lacunary anions with pyridine and pyridine-type ligands. Can. J. Chem.. In press... 

Pyridine-type ligands (g) Heterocyclic nitrogen ligands Cu(imidazole)6](N03)2 (183) CuN4Ni ETO 434... 

A theoretical study has been reported of the Heck reaction of electron-deficient arenes with alkenes catalysed by palladium(n) carrying a pyridine-type ligand. 

Tungsten - The NMR spectrum of y-[SiWio Fe(OH2) 2038] has been reported. i Solvent effects on the isotropic NMR shifts in quinuclidine and pyridine-type ligands coordinated to [SiWuCoOsg] " have been studied. ... 

The pressure dependence of the reaction of Ni + with NH3 has been studied in greater detail and the pH dependence of the nickel-imidazole reaction has been followed by Letter and Jordan. The complexing of nickel(n) by imidazole is unusual in that the protonated as well as the unprotonated form of the ligand reacts. For most unidentate ammonia- and pyridine-type ligands, protonation removes the only non-bonded electron pair on the ligand and the protonated form is not reactive. However, for imidazole one electron pair is essentially non-bonding even in the protonated form and can be used for complexation (Scheme 1). 

Figure 8.5.1. Dependence of n(k2/k i) in replacement of MeOH of [Co (PP)(MeO)(MeOH)] (5x10 M) by various pyridine type ligands (2xl0 - M) on their pK values at 25 °C. The descending branch is inferred to correspond to the decrease in metal —> ligand n bonding and the ascending branch to the increase of a bonding. " ...

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