We report a series of acylhydrazone‐based switches, of which double bond rotation can be stimulated by a pH response. The switches prefer Z rather than E configuration in the ground state because of the intramolecular hydrogen bonding, which was analyzed both thermodynamically and kinetically. Solvation studies show a linear relationship between the isomerization energy in Z/E states (ΔGE/Zo) of the switches and the hydrogen bond basicity scales (β and DN) of the solvent. This solvent effect was also found to be relative to the skeleton of compound, the less shield of hydrogen bond domain the more sensitivity to the solvent environment. By introducing multiple intramolecular hydrogen bonds, the Z isomer completely predominates for compound 4, offering an advantage over a full E/Z isomerization switching.

A series of quinoline–triazole oligomers self-assembled into quadruple helical structures is presented.

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