Selective Synthesis of [2]Rotaxane Orientational Isomers With Precisely Arranged Luminogens: Toward Orientation-Dependent Emissions for Information Storage and Encryption.

Aiming at the precise synthesis of rotaxane orientational isomers and the further elucidation of attractive orientation effects, a novel steric hindrance-controlled selective stopper exchange approach has been successfully developed. This method enables the facile and selective synthesis of six pairs of [2]rotaxane orientational isomers with precisely arranged luminogens, greatly enriching both the structural and functional diversity of such isomers. Notably, the resulting orientational isomers exhibit orientation-dependent emission behaviors, particularly in wavelengths, photoluminescence quantum yields, and circularly polarized luminescence (CPL) performances, endowing them with great potential for information storage and encryption. This proof-of-concept study provides not only a practical and efficient strategy for the efficient synthesis of rotaxane orientational isomers, but also a novel platform for constructing chiral luminescent materials with desired properties for wide applications.