Poly rare earth metal complexes

Chiral, poly(rare-earth metal) complexes in asymmetric catalysis (examples of reactions with participation or formation of heterocycles) 06AA31. 

Scheme 11 General reaction mechanism for poly rare earth metal complex-catalyzed asymmetric cyanation and azidation...

Shibasaki M, Kanai M. Catalytic enantioselective construction of tetrasubstituted carbons by self-assembled poly rare earth metal complexes. Org. Biomol. Chem. 2007 5 2027-2039. 

We developed various catalytic enantioselective cyanation and azidation reactions using chiral poly rare earth metal (RE) complexes derived from ligands 5-8 and TMSCN or TMSN3 as a stoichiometric nucleophile [43, 44]. General mechanism for those asymmetric catalyses is shown in Scheme 11. First, polymetallic complexes 9 containing defined higher order strucmres are generated via a reaction... 

Shima, T. and Hou, Z.M. (2006) Hydrogenation of carbon monoxide by tetranuclear rare earth metal poly-hydrido complexes. Selective formation of ethylene and isolation of well-defined polyoxo rare earth metal clusters. Journal of the American Chemical Society, 128, 8124. 

When rare-earth-metal ions such as Eu and Tb are bound to polyelectrolyte membranes such as poly(sodium acrylate) and poly(sodium ethene-sulphonate) their fluorescence intensities are considerably enhanced this is associated with the formation of asymmetric bonds between the rare-earth ions and the acrylate/S03 groups in the polymers. This was confirmed by the addition of EDTA to the Tb -poly(sodium acrylate) complex which, because of its preferential binding to the polymer, displaced Tb ions and resulted in reduced fluorescence of the latter. Stokes shifts of fluorescent dyes in different polymer systems have been related more to mobility effects in the polymer than polarity,and the fluorescence of hydrolysed aspirin has been found to be affected by the nature of different polymer supports.The luminescence properties of cis-(2,2 -bipyridyl)ruthenium(ii) complexes have been found to be influenced by binding the complex to a polymer matrix,as have the luminescence properties of flavones and l-octadecyl-3,3-dimethyl-6 -nitrospiro(indoline-2,2 -2H-benzopyran). Other studies of interest in-... 

---