This work demonstrates highly efficient solid‐state proton conduction in helical organic scaffolds inspired by the biomolecule gramicidin A. The scaffold, 1, derived from a pyridine‐2,6‐dicarboxamide (PDC) residue adopts a helical conformation that is stabilized by a network of strong bifurcated intramolecular H‐bonds between the polar residues that align the inner (concave) face of the molecule, while the aromatic units in 1 are oriented outwards. As a result, the helix attains an ambipolar nature just like gramicidin A. Two different solid forms of 1 could be isolated: a yellow solid from high‐polarity solvents and an orange solid from low‐polarity solvents. Single‐crystal X‐ray diffraction (SCXRD) studies showed that in the former, molecules of 1 are stacked in a homochiral fashion, while in the latter heterochiral stacks of 1 were present. The yellow form exhibited an almost ∼300‐fold higher conductivity (of up to 0.12 mS cm−1 at 95 °C and 95 % relative humidity) than the orange form as a result of closer intermolecular proximity and lower activation energy of 0.098 eV, thus indicating a Grotthus mechanism of proton transport. This study establishes the key role of bioinspired design and controlled stereo‐organization of such discrete uncharged organic molecules in achieving efficient solid‐state proton conduction.

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A bioinspired helical scaffold with high proton conductivity in the solid state is reported. The polar inner cavity of the scaffold is emphasized in light blue in the crystal structures of the two interconvertible solid forms shown in the center of the picture. The bulk coloration of the solid forms (yellow and orange) is reflected in the helices, and their homo‐ or heterochiral molecular organization is also shown. Proton conductivity is depicted by the blue double helix. More information can be found in the Research Article by A. Paul, S. Talukder, A. Srivastava and co‐workers (DOI: 10.1002/chem.202300019).