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In an approach to helical self-aggregation, C₂-symmetric cavity compounds based on the fusion of the bicyclo[3.3.1]nonane and indole framework and incorporating two 2-pyridone hydrogen-bonding motifs, compounds (−)-4 (pyrrole N-butyl) and (−)-5 (pyrrole N-decyl), have been synthesized. The 2-pyridone AD−DA hydrogen-bonding motif failed to operate in the solid state as demonstrated by X-ray diffraction analysis of (−)-4. Instead, the hydrogen-bonded (D−A) chains ···OC−N−H···OC−N−H···OC−N−H···, interconnecting columnar stacks, comprise helices of the right-handed (P) chirality motif. In solution, the aggregation of (−)-5 was studied by NMR, electronic, and CD spectroscopies, and VPO measurements. These investigations strongly suggest that (−)-5 associates to oligomers in CHCl₃ and CH₂Cl₂ using the 2-pyridone motif, fitting the equal K model, and that π-stacking can be ruled out as a mode of …