Brønsted Acid Catalyzed Stereoselective Polymerization of Vinyl Ethers.

Autor: Knutson PC; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States., Teator AJ; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States., Varner TP; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States., Kozuszek CT; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States., Jacky PE; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States., Leibfarth FA; Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, United States.
Jazyk: angličtina
Zdroj: Journal of the American Chemical Society [J Am Chem Soc] 2021 Oct 13; Vol. 143 (40), pp. 16388-16393. Date of Electronic Publication: 2021 Oct 01.
DOI: 10.1021/jacs.1c08282
Abstrakt: Isotactic poly(vinyl ether)s (PVEs) have recently been identified as a new class of semicrystalline thermoplastics with a valuable combination of mechanical and interfacial properties. Currently, methods to synthesize isotactic PVEs are limited to strong Lewis acids that require a high catalyst loading and limit the accessible scope of monomer substrates for polymerization. Here, we demonstrate the first Brønsted acid catalyzed stereoselective polymerization of vinyl ethers. A single-component imidodiphosphorimidate catalyst exhibits a sufficiently low p K a to initiate vinyl ether polymerization and acts as a chiral conjugate base to direct the stereochemistry of monomer addition to the oxocarbenium ion reactive chain end. This Brønsted acid catalyzed stereoselective polymerization enabled an expanded substrate scope compared to previous methods, the use of chain transfer agents to lower catalyst loading, and the capability to recycle the catalyst for multiple polymerizations.
Databáze: MEDLINE
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