ja034001d_si_001.pdf (6.41 MB)
A Folded, Secondary Structure in Step-Growth Oligomers from Covalently Linked, Crowded Aromatics
journal contribution
posted on 2003-03-28, 00:00 authored by Wei Zhang, Dana Horoszewski, John Decatur, Colin NuckollsThis study delineates general methods to create a new class of folded oligomers by covalently
attaching overcrowded aromatics to each other. Crucial to observing the secondary structure in these
oligomers was the employment of C-shaped linkers. These linkers preorganize the strands to form
intramolecular hydrogen bonds. In solution, one- and two-dimensional 1H NMR data show well-defined
columnar conformations. The side chains in these oligomers are critical for the secondary structure to
emerge in solution. Using tris(dodecyloxy)phenethyl side chains in combination with tert-butyl side chains
in the terminal subunit provides a soluble trimer and prevents intermolecular association above millimolar
concentrations. This new folding motif, formed through a synergy between hydrogen bonds and π-stacking,
is so robust that even dimers have secondary structure in solution.