Generation-Independent Dimerization Behavior of Quadruple Hydrogen-Bond-Containing Oligoether Dendrons
摘要:
A new series of self-assembling G1-G3 dendronized dimers bearing oligoether dendrons and a dimeric 2-ureido-4-pyrimidinone (UPy) quadruple hydrogen-bonding core were prepared and characterized. It was found that the nonpolar microenvironment created by the dendrons preserved the UPy unit in its DDAA tautomeric form. As a result, the stabilities of the dimers were exceptionally strong for all three generations (K-dim(.) > 2 x 10(7) M-1 in CDCl3 at 25 degrees C). Furthermore, the steric size of the dendrons did not exhibit a significant effect on their dimerization behavior.
The Introduction of Asymmetry into Alkyl-Decorated Fréchet-Type Dendrons
作者:Edwin C. Constable、Stefan Graber、B. A. Hermann、Catherine E. Housecroft、Michael S. Malarek、Lukas J. Scherer
DOI:10.1002/ejoc.200800134
日期:2008.5
A strategy for the introduction of asymmetry into Frechet-typedendrons bearing n-alkyl chains is described. Starting from a methyl 3,5-dihydroxybenzoate core, 3,5-bis(octyloxyphenyl)methoxy and 3,5-bis(alkoxyphenyl)methoxy units are introduced in a stepwise manner. The method is illustrated by the syntheses of four representative compounds having mixed n-octyl/n-butyl, n-octyl/n-hexyl, n-octyl/n-heptyl
Sonication-induced self-assembly of flexible tris(ureidobenzyl)amine: from dimeric aggregates to supramolecular gels
作者:Chao Deng、Ru Fang、Yangfan Guan、Juli Jiang、Chen Lin、Leyong Wang
DOI:10.1039/c2cc33408a
日期:——
Tris(ureidobenzyl)amine derivatives 1a,b form dimeric aggregates in apolar solution and in the solid state. Specifically, the meta-substituted tris(urea) 1a is able to transform into supramolecular gels in certain solvents via sonication.