A ferrocene-based pseudopeptide chiroptical switch

Dalton Trans. 2021 Apr 7;50(13):4504-4511. doi: 10.1039/d1dt00508a. Epub 2021 Mar 15.

Abstract

We present a double-stranded ferrocene pseudopeptide 2b which exhibits stimuli responsive chirality inversion triggered by solvent exchange or acid addition. Compound 2b exists as a mixture of self-assembled fast exchanging oligomers which macroscopically behave as a chiroptical switch with two stable states. The ferrocene group inversion results in a distinct CD signal in the visible part of the spectrum. The inversion is accomplished through a conformational change due to a rearrangement of hydrogen bonding forcing the rotation of ferrocene rings.