| Abstract
| - We previously reported the synthesis and solution characterization of short o-phenylene ethynylene (oPE)foldamers. Proton correlation techniques are not adequate for NMR assignment in these compounds asthe ethynylene linkers interrupt proton connectivity. In order to facilitate structural characterization andmore fully harness the power of NMR, it is necessary to know the sequence of spin systems along themolecular backbone. For example, spin system assignment is required to unambiguously assign NOEcorrelations for structural determination of folded forms in solution. Therefore, we developed a methodto assign the aromatic spin systems in these compounds using HMBC experiments. This has been performedfor tetrameric (Es4), pentameric (Es5), and hexameric (Es6) oligomers and is expected to prove useful forthis class of foldamers in general. The proton assignments obtained by this technique have been usefultoward confirming the previous hypotheses of helical folding in oPE systems.
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