Helicates self-assembled

Chiral Columns Formed by Helical Self-Assembly... 

Elhabiri, M. Scopelliti, R. Biinzli, J.-C. G. Piguet, C. Lanthanide helicates self-assembled in water a new class of highly stable and luminescent dimetallic carboxy-lates. J. Am. Chem. Soc. 1999,121,10747-10762. 

Kramer, R., Lehn, J.M. and Marquis-Rigault, A. (1993) Self-recognition in helicate self-assembly Spontaneous formation of helical metal complexes from mixtures of ligands and metal ions. 

R. Kramer, J.-M. Lehn, A. Marquis-Rigault, Self-Recognition in Helicate Self-Assembly Spontaneous Formation of Helical Metal Complexes from Mixtures of Ligands and Metal Ions , Proc. Natl. Acad. Sci. USA, 90, 5394 (1993)... 

J.H.K.K. Hirschuberg, L. Brunsveld, A. Ramzi, J.A.J.M. Vekemans, R.P. Sijbesma, E.W. Meijer, Helical Self-Assembled Polymers from Cooperative Stacking of Hydrogen-Bonded Pairs , Nature, 407, 167 (2000)... 

Lehn et a/7 have described the helical self-assembly process in the following terms ... 

Inorganic double or triple helices are formed by two or three ligand strands wrapped around linearly disposed metal ions [13], Among cyclic transition metal complexes, circular helicates [nJ cH [ ] "cH is a general notation characterizing circular helicates (cH) with n = number of metal ions and m = helicity (m = 2 for a double helix) have specific features and may be considered as toroidal helices [34]. There are two different kinds of circular helical systems. Some structures self-assemble from the metal ions and the ligands only in the presence of an anion, which could act as a template [34,35,64-67], whereas, in other cases, the circular helicates self-assemble from the metal ions and the ligands alone [68-70]. 

Modeling lanthanide helicate self-assembly in solution... 

The use of the hydrolyzed ligand [L13 ] introduces charge neutralization as a novel parameter in helicate self-assembly. In these conditions, the coordination of a second metal to a single strand in [R2(L13 )] " competes with the fixation of a second ligand in [R(L13 )2] (Figure 58B ... 

Sanchez-Quesada, J. Seel, C. Prados, P. de Mendoza, J. Anion helicates Double strand helical self-assembly of chiral bicyclic guanidinium dimers and tetramers around sulfate templates. J. Am. Chem. Soc. 1996, 118 (1), 277-278. 

Hirschberg, J.H.K.K. Bmnsveld, L. Ramzi, A. Vekemans, J.A.J.M. Sijbesma, R.P. Meijer, E.W. Helical self-assembled polymers from cooperative stacking of hydrogen-bonded pairs. Nature 2000, 407, 167- 170. 

Cai C, Lin J, Chen T, Wang X, Lin S (2009) Super-helices self-assembled from a binary system of amphiphilic polypeptide block copolymers and polypeptide homopolymers. Chem Commun 2709-2711... 

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