Trans-chelating ligand

Cr(I) [A] (3dy Coordination compounds with neutral and chelating ligands trans-[CrCl(NOXdas)2]C104 0.95 1.70 Farad probably 69F1... 

In rhenium compounds that contain two metal-imido ligands, these tend not to occupy positions trans to one another for the same reason. A trigonal-bipyramidal geometry has been identified in 2 and 3, even to the extent that the potentially chelating ligand Ph2PCH2PPh2 acts as a monodentate ligand. 

In most protein structures that have been published so far, the 2-OG cosubstrate is bound as a chelate ligand to Fe(II) with the 2-oxo group trans to the aspartate (32). Until now in none of these has a geometry... 

The complex [Ru(NO)(NH3)(S4)2] has been prepared and crystallographically characterized. It contains two 84 chelating ligands, and the NO and NH3 ligands are mutually trans. This complex was the first polysulfido nitrosyl complex of ruthenium. ... 

Furthermore, the heterolysis reaction is catalyzed by the addition of anions (organic and inorganic oxy anions, e.g., acetate) (44,107, 110,111). Comparing the acetate effect in the presence of different chelating ligands ([15]aneN4 and nta) to those of the aquated system led to the conclusion that the oxy anions have to occupy the trans position to the R group in order to labilize the M-R bond (trans labilization effect) and thus catalyze the heterolytic decomposition (44,107,110,111). 

Jimenez-Rodriguez, C., Roca, F.X., Bo, C, Benet-Buchholz, )., Escudero-Adan, E.C., Ereixa, Z. and van Leeuwen, P.W.N.M. (2006) SPANphos trans-sparming diphosphines as cis chelating ligands . Dalton Trans., 268-278. 

There are several mechanisms that are possible for such an inversion, some of which can be eliminated by appropriate experiments. For example, one mechanism would involve complete dissociation of one chelating ligand with formation of a square planar or a trans diaqua complex as a first step ... 

NiL2Py2 2-Methoxy-4-nitrophenolate trans Oh chelate ligand Oh B = py, H20, tmd 1504... 

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