Azpy ligands

The search for new coordination SCO polymers based on the assembling of iron(II) and bridging molecules other than 1,2,4-triazole- or l-i -tetrazole-based ligands has afforded a series of frameworks closely related to the 2D system [Fe(btr)2(NCX)2]-H20 (X=S, Se). This series of compounds formulated as [FeL2(NCS)2]-nSolv can be considered as derived from the formal substitution of btr by bis-monodentate pyridine-like ligands such as bispyridylethylene (bpe, n=l, Solv=MeOH), fraus-4,4 -azopyridine (azpy,... 

Completely different behaviours are observed in the coordination polymers constructed from azpy and bped ligands (Fig. 23), in which guest ethanol molecules... 

Photoreactions of [Ru(bipy)3]Cl2 and of [Ru(phen)3]Cl2 in acetonitrile proceed more slowly as pressure increases. The activation volumes increase dramatically with temperature, from +12 and +9 cm mol respectively at 288 K to +22 and +27 at 333 K. These increases are ascribed to a key role for chloride ion pairs in these dissociatively activated reactions. Rate constants for base-catalyzed isomerization of the y to the p form of [Ru(azpy)2Cl2], azpy = (22), are not linear in hydroxide concentration, prompting speculation on the detailed role of hydroxide in this conversion.Rate constants for replacement of coordinated water in cis- and tra 5-[Ru(LL)2X(OH2)]" by acetonitrile span a range of nearly 2 X 10" times. Several factors have to be invoked to explain the observed trend in the effects of ligand X on the ease of replacement of the aqua-ligand. " The... 

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