A supramolecular helix that disregards chirality
Cécile Roche, Hao-Jan Sun, Pawaret Leowanawat, Fumito Araoka, Benjamin E. Partridge, Mihai Peterca, Daniela A. Wilson, Margaret E. Prendergast, Paul A. Heiney, Robert Graf, Hans W. Spiess, Xiangbing Zeng, Goran Ungar & Virgil Percec
Affiliations Contributions Corresponding author
Nature Chemistry 8, 80–89 (2016) doi:10.1038/nchem.2397
Received 19 April 2015 Accepted 14 October 2015 Published online 16 November 2015
Source/Fonte: Nature Chemistry
The functions of complex crystalline systems derived from supramolecular biological and non-biological assemblies typically emerge from homochiral programmed primary structures via first principles involving secondary, tertiary and quaternary structures. In contrast, heterochiral and racemic compounds yield disordered crystals, amorphous solids or liquids. Here, we report the self-assembly of perylene bisimide derivatives in a supramolecular helix that in turn self-organizes in columnar hexagonal crystalline domains regardless of the enantiomeric purity of the perylene bisimide. We show that both homochiral and racemic perylene bisimide compounds, including a mixture of 21 diastereomers that cannot be deracemized at the molecular level, self-organize to form single-handed helical assemblies with identical single-crystal-like order. We propose that this high crystalline order is generated via a cogwheel mechanism that disregards the chirality of the self-assembling building blocks. We anticipate that this mechanism will facilitate access to previously inaccessible complex crystalline systems from racemic and homochiral building blocks.
Subject terms: Organic chemistry Self-assembly
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PERGUNTA DESTE BLOGGER:
E agora José, como é que fica aquela história de homoquiralidade sendo um fenômeno especial e coisa e tal???