We describe a novel Binol‐containing macrocycle that behaves as a chiroptical probe for the detection of biologically relevant ions (Cu2+, Zn2+) under physiological conditions. The macrocycle synthesis is carried out with Binol‐based synthons suitably derivatized in the 2,2′‐ and 3,3′‐positions, by means of a room temperature esterification reaction as the cyclization procedure, followed by late‐stage unmasking of the four carboxylic acid functionalities embedded within the macrocyclic framework. The recognition events, signaled using both UV and CD spectroscopy, are triggered by macrocyclic rearrangement induced by binding of the cations through coulombic interactions with the carboxylate anions in water at pH 7. The ample CD response ensures high chiroptical sensitivity and demonstrates the feasibility of chiroptical detection of biologically relevant cations by using a non‐nitrogen‐based ligand under aqueous conditions.

SummaryWe report on the synthesis and characterization of novel shape-persistent, optically active arylamide macrocycles, which can be obtained using a one-pot methodology. Resolved, axially chiral binol scaffolds, which incorporate either methoxy or acetoxy functionalities in the 2,2' positions and carboxylic functionalities in the external 3,3' positions, were used as the source of chirality. Two of these binaphthyls are joined through amidation reactions using rigid diaryl amines of differing shapes, to give homochiral tetraamidic macrocycles. The recognition properties of these supramolecular receptors have been analyzed, and the results indicate a modulation of binding affinities towards dicarboxylate anions, with a drastic change of binding mode depending on the steric and electronic features of the functional groups in the 2,2' positions.