β-D-Galactose-Functionalized Pillar[5]arene With Interesting Planar-Chirality for Constructing Chiral Nanoparticles
Guangping Sun1, Liangtao Pu2, Srikala Pangannaya1
1Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, China.
Frontiers in Chemistry
|December 6, 2019
Summary
Synthesized planar-chiral pillar[5]arenes with galactose substituents (GP5) were successfully separated and retained their chirality. These chiral GP5 molecules form self-assembled nanoparticles, acting as reliable chiral sources.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Chiral Materials
Background:
- Pillar[5]arenes are macrocyclic compounds with potential applications in host-guest chemistry.
- Controlling chirality in macrocyclic systems is crucial for developing advanced functional materials.
Purpose of the Study:
- To synthesize and characterize planar-chiral pillar[5]arenes functionalized with β-D-galactose.
- To investigate the chiral properties and stability of these novel compounds.
- To explore their potential as chiral sources in supramolecular self-assembly.
Main Methods:
- Synthesis of β-D-galactose functionalized pillar[5]arenes.
- Separation of enantiomers using silica gel chromatography.
- Characterization using dynamic 1H NMR and Circular Dichroism (CD) spectroscopy.
- Host-guest complexation studies and self-assembly into nanoparticles.
Main Results:
- High-yield synthesis and effective chromatographic separation of (S)- and (R)-β-D-galactose functionalized pillar[5]arenes (GP5).
- GP5 enantiomers exhibit stable S and R planar chirality, confirmed by NMR and CD spectra, with no racemization.
- GP5 forms host-guest complexes with DNS-CPT, leading to supramolecular amphiphiles that self-assemble into chiral nanoparticles retaining the original GP5 chirality.
Conclusions:
- Planar-chiral GP5 molecules are successfully synthesized and resolved.
- GP5 enantiomers are configurationally stable and can serve as reliable chiral sources.
- The retained chirality of GP5 in self-assembled nanoparticles highlights their potential in chiral supramolecular chemistry.
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