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Published on: August 1, 2018
Dynamic polythioesters via ring-opening polymerization of 1,4-thiazine-2,5-diones
Yasuyuki Ura1, Mohammad Al-Sayah, Javier Montenegro
1Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Abstract:
We describe the preparation and characterization of polythioesters composed of alternating alpha-amino acid and alpha-thioglycolic acid residues that undergo dynamic constitutional exchange under mild conditions. The polymers are assembled via reversible ring-opening polymerizations of 1,4-thiazine-2,5-diones and related monomers in solution-phase conditions that do not require the use of transition metal catalysts. Because 1,4-thiazine-2,5-diones can be derived in part from alpha-amino acids, a variety of side chain functionalized monomers in optically pure forms could readily be accessed. In addition, the resulting polythioesters have the potential for intra- and inter-chain hydrogen bonding, which is known to impart materials properties to other previously studied polyamides. The studies reported here could be useful in advancing a new class of biodegradable polymers and furthermore suggest that dynamic constitutional exchange could be exploited to modify many known synthetic and natural polythioesters.
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