Photo-controlled Chirality Transfer and FRET Effects based on Pseudorotaxane
The use of light to regulate the chirality of supramolecular assemblies in a non-invasive manner remains a challenge. Herein, we reported a novel photochromic pseudorotaxane based on (R/S)-2,2'-binaphthyl secondary ammonium salt guest (2) and anthracene-bridged bis(dibenzo-24-crown-8) (1), which featurs a chirality transfer and fluorescence resonance energy transfer (FRET) from 2 to 1. Benefiting from the photo-oxidation of anthracene, the induced circular dichroism (ICD) signals of (R/S)-2@1 can be switched off / on by irradiation with 365 nm UV light and heating. This noncovalent supramolecular assembly strategy provides us with unique opportunities to design and construct more smart photo-responsive chiral molecular switches.