N-Boc-Protected 1,2-Diphenylethylenediamine-Based Dendritic Organogels with Multiple-Stimulus-Responsive Properties.

A new class of poly(benzyl ether) dendrimers, decorated in their cores with N-Boc-protected 1,2-diphenylethylenediamine groups, were synthesized and fully characterized. It was found that the gelation capability of these dendrimers was highly dependent on dendrimer generation, and the second-generation dendrimer ( R, R)-G2DPENBoc proved to be a highly efficient organogelator. A number of experiments (SEM, TEM, FTIR spectroscopy, 1H NMR spectroscopy, rheological measurements, UV/Vis absorption spectroscopy, CD, and XRD) revealed that these dendritic molecules self-assembled into elastically interpenetrating one-dimensional nanostructures in organogels. The hydrogen bonding, π-π, and solvophobic interactions were found to be the main driving forces for formation of the gels. Most interestingly, these dendritic organogels exhibited smart multiple-stimulus-responsive behavior upon exposure to environmental stimuli such as temperature, anions, and mechanical stress. [ABSTRACT FROM AUTHOR]