Chemistry of Materials
Article
The chiral resolution efficiency (e.e., enantiomeric excess) in
the enantioselective crystallization process was subsequently
investigated, as presented in Figure 13. This was accomplished
AUTHOR INFORMATION
Corresponding Author
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Notes
The authors declare no competing financial interest.
ACKNOWLEDGMENTS
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This work was supported by the National Natural Science
Foundation of China (21274008, 21174010), the Funds for
Creative Research Groups of China (51221002), and the
“Specialized Research Fund for the Doctoral Program of
Higher Education” (SRFDP 20120010130002).
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Figure 13. Enantiomeric excess of the residual solution after
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4. CONCLUSIONS
We have for the first time attached optically active polymer-
based nanoparticles on GO by chemical bonds. Such a practice
improved the dispersibility of the polymer nanoparticles. Since
the nanoparticles were constructed by chirally helical-
substituted polyacetylene, they rendered GO with interesting
optical activity. Meanwhile, the attachment of polymer
nanoparticles also enhanced the dispersibility of GO in organic
solvent (e.g., THF). The novel GO hybrid material was
achieved via catalyst emulsion polymerization of a substituted
acetylene monomer, in the presence of alkynylated GO. The
−CC groups on GO took part in emulsion polymerization,
by which the as-formed polymer nanoparticles were chemically
immobilized on the surfaces of GO. Because of the presence of
the optically active nanoparticles constructed by helical polymer
chains of one predominant screw sense, NPpoly1/GO efficiently
induced enantioselective crystallization of racemic alanine
enantiomers. The success achieved in the present work is far
beyond the novel GO hybrid. The present facile approach can
be taken as a versatile platform, hopefully extended to other
helical and even nonhelical polymers for functionalizing
graphene (GO), thereby leading to a number of novel
graphene-based advanced materials, in particular chiral
materials.
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dx.doi.org/10.1021/cm500211s | Chem. Mater. 2014, 26, 1948−1956