Controllable Supramolecular Chiral Twisted Nanoribbons from Achiral Conjugated Oligoaniline Derivatives.

The fabrication of supramolecular chiral nanostructures from achiral materials without the need of pre-existing chirality is a major challenge associated with the origin of life. Herein, supramolecular chiral twisted nanoribbons of achiral oligoaniline derivatives were prepared via simply performing the chemical oxidation of aniline in an alcohol/water mixed solvent. In particular, the supramolecular chirality of the twisted nanoribbons could be controlled by facilely tuning the alcohol content in the mixed solvent. A tetra-aniline derivative CHON was attested to be the major component of the obtained nanoribbons. The main driving forces for the assembly of the oligoaniline derivative into twisted nanoribbons might be the π-π stacking and hydrogen bonding interactions among the chains which could be modulated by the alcohol content in the mixed solvent. The single-handed twisted nanoribbons could be used to separate chiral phenylalanine from a racemic mixture. Thus, it is highly anticipated that the supramolecular chirality endows π-conjugated molecules with potential application in chiral recognition.