1206796-41-9Relevant academic research and scientific papers
Liquid-crystalline self-organization of isocyanide-containing dendrimers induced by coordination to gold(I) fragments
Cordovilla, Carlos,Coco, Silverio,Espinet, Pablo,Donnio, Bertrand
supporting information; experimental part, p. 1424 - 1431 (2010/04/01)
Dendritic polyisocyanides can be considered as promising polytopic ligands to generate a great diversity of metallodendrimers due to the ability of the isocyanide moiety to bind to various transition metals. Here, new isocyanide-containing dendrimers and their corresponding polynuclear gold complexes have been prepared, [Gi(NC)Z] and [G i(NCAuR)Z], respectively, where Gi is a poly(phenyl ether) dendrimer, i is the generation number (i = 0, 1, or 2), Z is the number of peripheral groups (Z ) 3 x 2i), and AuR are the surface groups ([R ) Cl, C≡C-C6H4-OC12H 25, C≡CC6H2(OC12H 25)3]. The compounds are derived from a highly flexible phenyl ether-based dendritic core, Gi, having the general formula G0 = C6H3(OC11H22OC6H 4-)3, G1 ) C6H3[OC 11H22OC6H3(OC11H 22OC6H4-)2]3, G 2 = C6H3[OC11H22OC 6H3{OC11H22OC6H 3(OC11H22OC6- H4-) 2}2]3), growing from the trivalent phloroglucinol and with undecylene aliphatic spacers between each branching benzene ring and end-functionalized by isocyanide groups. As in their monomeric model counterparts, stable liquid-crystalline phases are induced upon complexation of the AuR gold moieties at the branch termini. The nature of the anionic ligand R promotes the appearance of smectic or columnar mesophases, the formation of which are governed by steric and dipolar interactions. Based on X-ray diffraction experiments, models describing the supramolecular organization of these metallodendrimers into smectic and columnar mesophases are proposed: columnar phases result from the one-dimensional stacking of molecular disks made of self-assembled supermolecules in oblate cylindrical conformation, while the smectic phases form by the lateral two-dimensional registry of the supermolecules in antiparallel head-to-head prolate conformation.
