Year: 2026
Type: preprint
Abstract: Biological systems selectively use chiral molecules, such as L-amino acids and D-sugars, to construct single-handed helical structures including proteins, collagen, and DNA. Reproducing such handedness selection using synthetic systems remains a major challenge because achiral molecules generally form racemic helices. Here, we show that supramolecular halogen-bonded complexes assembled entirely from achiral molecular components spontaneously form either left- or right-handed helices. Structural analysis reveals that helix formation is driven by cooperative hydrogen-bonding interactions within the halogen-bonded assemblies, while their handedness is determined solely by the solvent. Remarkably, homochiral helices emerge without the need for chiral catalysts, chiral solvents, or other external chiral influences. These findings provide experimental evidence for spontaneous symmetry breaking in an achiral molecular system and offer a simple platform for exploring the origins of homochirality.
Source: ChemRxiv
Author: Rakesh Puttreddy
Institution: University of Jyväskylä
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
Funder: Suomen Kulttuurirahasto
OpenAlex ID: W7223171583