Dipeptide heterochirality directs global chirality and mesoscale morphology during supramolecular co-assembly.

HYPOTHESIS: The origin of biological homochirality and the principles governing heterochiral molecular interactions remain poorly understood. In self-assembling chiral systems, a linear CD-ee relationship generally indicates self-sorting driven by unfavorable heterochiral interactions, whereas nonlinear CD-ee dependences often give rise to the majority-rule effect. This work reports an unusual "minority-preference" behavior in the co-assembly of dipeptide-tetraphenylethylene conjugates with homochiral or heterochiral configurations.

EXPERIMENTS: Co-assembly of the two homochiral counterparts, LALA and DADA, exhibits a typical majority-rule. Strikingly, co-assembly of LALA with the heterochiral molecule LADA yields a completely different outcome: even a low fraction of the homochiral component dictates the supramolecular helicity and transforms the morphology from nanotubes into chiral nanoscrolls.

FINDINGS: Detailed NMR analyses and DFT analyses reveal that cooperative heterochiral interactions promote asymmetric molecular packing and chirality amplification, enabling the minor component to dominate the co-assembled system. Furthermore, the assemblies exhibit tunable circularly polarized luminescence. This work advances the fundamental understanding of chiral communication in non-covalent systems and provides a molecular platform for designing adaptive chiroptical materials.