Ligand imidazole-based

Recently, structural and functional models that somewhat more closely mimic the coordination environment of the active site of CcO have been developed. These possess an axial ligand imidazole base, three or four N-ligands to Cu, and a phenol moiety to study HCO active site models of the His-Tyr enzyme... 

These results suggest that imidazolidin- and imidazol-based skeletons transfer similar amounts of electron density to the metal. The conclusion that changes in the bridge of the NHC skeleton have such a small effect on the electronic properties of the NHC is quite surprising, considering that SIMes- and IMes-based catalysts often show remarkably different catalytic behaviour. It is still unclear if these small changes in the electronic properties of the NHC ligand confer such different catalytic behaviours, or other effects (steric, flexibility, etc.) should be invoked. 

Table 2 Stereochemistries of copper(II) complexes of imidazole-based chelating ligands.

From the standpoint of modeling Type I copper proteins,4,5,59,60 a variety of imidazole-based ligands containing thioether sulfurs and imidazole groups have been synthesized.61,62 The structures and spectroscopic properties of their copper(II) complexes (51)-(53) and (55)-(60) were investigated.65,79-82 To characterize apical copper(II)-thioether bonding, the complex (51) was... 

Liu W et al (2010) Compact biocompatible quantum dots viaRAFT-mediated synthesis of imidazole-based random copolymer ligand. J Am Chem Soc 132 472-83... 

Figure 4.48 Imidazole-based species used as ligands in Au/Ag heterometallic compounds.

Rho and Ha ° synthesized a series of Ir complexes with a variety of imidazole-based ligands (L = dpi, tmspi). The [Ir(acac)(L)2] complexes do not exhibit emission. DFT calculations show that the LUMO energy levels of dpi and tmspi are similar to that of acac in these complexes, leading to an ET process involving the dpi and tmspi ligands and landing on a non-radiative channel that quenches the emission. 

Reactions of a well-known complex, [Cr(Me)Cl2(thf)3],300 with imidazole-based ligands in anhydrous solvents led to the isolation of new Cr111 methyl complexes (e.g., (77)).301... 

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