Elucidating the structure of the Pm3n cubic phase of supramolecular dendrimers through the modification of their aliphatic to aromatic volume ratio.
The synthesis, and structural and retrostructural analysis of a library of second-generation conical dendrons that self-assemble into spherical supramolecular dendrimers is reported. This library consists of amphiphilic dendrons with n-alkyl groups containing from 4 to 16 carbon atoms. The dendrons containing 6 to 16 carbon atoms in their n-alkyl groups self-assemble into spherical supramolecular dendrimers that self-organize in a Pm3n cubic lattice. The structural and retrostructural analysis of the Pm3n lattices generated from the supramolecular dendrimers demonstrated that the volume of the aromatic core of the spherical dendrimers is not dependent on the number of carbon atoms from their alkyl groups. This result facilitated the calculation of the average values of the absolute electron density of the aliphatic and aromatic domains of the spherical supramolecular dendrimers. The relative intensity of the higher order diffraction peaks of the Pm3n lattice increases as the volume of the aliphatic part of the sphere mediated by the number of carbon atoms in the n-alkyl groups decreases. This study demonstrates the maximum increase of the relative intensity of the higher order diffraction peaks of the Pm3n lattice generated from non-hollow supramolecular dendrimers.
Percec
Virgil
V
Roy & Diana Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104-6323, USA. percec@sas.upenn.edu
Peterca
Mihai
M
Tsuda
Yusuke
Y
Rosen
Brad M
BM
Uchida
Satoshi
S
Imam
Mohammad R
MR
Ungar
Goran
G
Heiney
Paul A
PA
D003460:Crystallization; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry*; D005227:Fatty Acids / Q000138:chemical synthesis / Q000737:chemistry*; D008968:Molecular Conformation; D015394:Molecular Structure
D050091:Dendrimers; D005227:Fatty Acids