Self-Assembling Dendrimers

Abstract

Hydrogen bond-mediated self-assembly is a powerful strategy for generating large structures from smaller subunits. The synthesis of molecules containing two isophthalic acid units covalently attached to a rigid aromatic spacer is described. By normal pairing of carboxylic acids into hydrogen-bonded dimers, these molecules self-assemble in organic solvents to form either a series of linear aggregates or a cyclic hexamer. These molecules were linked to the core of a family of polyether dendrimers, which caused the hexamer to be formed preferentially. The stability of the hexamer depended on the generation number of the dendrimer. The largest of these hydrogen-bonded macromolecular assemblies is roughly disk-shaped with a 9-nanometer diameter and a 2-nanometer thickness. Its size and molecular mass (34,000 daltons) are comparable to that of small proteins.

Nature of the effective interaction between dendrimers

“…These molecules are also very important in the field of nanotechnology. Self-assembly of nanoparticles mediated by dendrimers is becoming a growing field of research [16][17][18][19][20][21][22][23][24][25] . Dendrimers are used as spacer to control the inter-particle distance in nanocomposites, which has a strong influence on the optical 16 , electronic and magnetic properties 26 of the nanocomposites.…”

Generation-Dependent Energy Dissipation in Rigid Dendrimers Studied by Femtosecond to Nanosecond Time-Resolved Fluorescence Spectroscopy

“…For this reason, dendrimers have been attracting much attention not only from the synthetic point of view 3 but also from the point of view of their physical and chemical properties. [4][5][6][7][8][9] Dendrimers consist of an interior building block (core) surrounded by successive branched layers, the so-called generations, and a periphery. 10 A broad range of applications for dendrimers has been reported in several fields such as guesthost chemistry, 11 analytical chemistry, 12 optoelectronics, 13 catalysis, 14 biology, 15 and medicine.…”

Dendrimers and supramolecular chemistry

“…In contrast, purity and structural uniformity are harder to maintain in the divergent approach, because the number of reactions that must be completed at each step of growth increases exponentially requiring large excesses of reagents, but the process is better suited not only for syntheses on a larger scale but also for the preparation of high-generation dendrimers. Although the majority of the dendrimers prepared to-date have been built of covalent bonds (3,10), many noncovalent dendrimers (3,11) have also been prepared by a variety of selfassembly processes involving, for example, hydrogen bonding (12) or supramolecular coordination chemistry (13).…”