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  • Quantitative, Regiospecific, and Stereoselective Radical Ring-Opening Polymerization of Monosaccharide Cyclic Ketene Acetals
Title: Quantitative, Regiospecific, and Stereoselective Radical Ring-Opening Polymerization of Monosaccharide Cyclic Ketene Acetals
Cyclic ketene acetals (CKAs) are among the most well-studied monomers for radical ring-opening polymerization (rROP). However, ring-retaining side reactions and low reactivities in homopolymerization and copolymerization remain significant challenges for existing CKAs. Here, we report that a class of monosaccharide CKAs can be facilely prepared from a short and scalable synthetic route and can undergo quantitative, regiospecific, and stereoselective rROP. NMR analyses and degradation experiments revealed a reaction mechanism involving a propagating radical at the C2 position of pyranose, with different monosaccharides exhibiting distinct stereoselectivity in the radical addition of the monomer. Furthermore, adding maleimide was found to improve the incorporation efficiency of the monosaccharide CKA in the copolymerization with vinyl monomers, producing unique degradable terpolymers with carbohydrate motifs in the polymer backbone.  more » « less
Award ID(s):
1944512 2117246
PAR ID:
10497355
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
146
Issue:
8
ISSN:
0002-7863
Page Range / eLocation ID:
5056 to 5062
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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