Cited by 278biodegradable polymer synthesis and propertiesCarbon dioxide utilization in catalysisAdvanced Polymer Synthesis and Characterization

Urea Anions: Simple, Fast, and Selective Catalysts for Ring-Opening Polymerizations

Lin, Binhong, Waymouth, Robert M.·2017·Journal of the American Chemical Society

Abstract

Aliphatic polyesters and polycarbonates are a class of biorenewable, biocompatible, and biodegradable materials. One of the most powerful methods for accessing these materials is the ring-opening polymerization (ROP) of cyclic monomers. Here we report that the deprotonation of ureas generates a class of versatile catalysts that are simultaneously fast and selective for the living ring-opening polymerization of several common monomers, including lactide, δ-valerolactone, ε-caprolactone, a cyclic carbonate, and a cyclic phosphoester. Spanning several orders of magnitude, the reactivities of several diaryl urea anions correlated to the electron-withdrawing substituents on the aryl rings. With the appropriate urea anions, the polymerizations reached high conversions (∼90%) at room temperature within seconds (1-12 s), yielding polymers with narrow molecular weight distributions (Đ = 1.06 to 1.14). These versatile catalysts are simple to prepare, easy to use, and exhibit a range of activities that can be tuned for the optimal performance of a broad range of monomers.

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Crossref · 10.1021/jacs.6b11864

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69 of 69 references verified0 citation errors · 0 not checkable

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  • A class of (thio)urea anions catalysts were disclosed that exhibit both high activity and selectivity for the ROP of a variety of cyclic esters and carbonates.

    “Recently a class of (thio)urea anions catalysts were disclosed that exhibit both high activity and selectivity for the ROP of a variety of cyclic esters and carbonates (Scheme 12).321,336”

    From Catalysis as an Enabling Science for Sustainable Polymers (2018) · cites this paper as [336]

  • Urea anions are more active than the corresponding thiourea anions, with the ability to polymerize all tested monomers in just seconds (<12 s) with excellent control on molecular weight distributions (Ð = 1.06-1.14).

    “The urea anions are more active than the corresponding thiourea anions, with the ability to polymerize all tested monomers in just seconds (<12s) with excellent control on molecular weight distributions (Ð =1.06 ~ 1.14).336”

    From Catalysis as an Enabling Science for Sustainable Polymers (2018) · cites this paper as [336]

  • These ionic catalysts are prepared by simple deprotonation of the neutral ureas or thioureas.

    “These ionic catalysts are prepared by simple deprotonation of the neutral ureas or thioureas.”

    From Catalysis as an Enabling Science for Sustainable Polymers (2018) · cites this paper as [336]

  • The rate of the polymerization can be tuned over several orders of magnitude by modifying the urea or thiourea substituents.

    “The rate of the polymerization can be tuned over several orders of magnitude by modifying the urea or thiourea substituents.”

    From Catalysis as an Enabling Science for Sustainable Polymers (2018) · cites this paper as [336]

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Authors
Lin, B., & Waymouth, R. M.
Affiliations
Stanford University (US)
Corresponding author
Waymouth, Robert M.
Venue
Journal of the American Chemical Society
Published
2017-01-20
Volume
139
Issue
4
Pages
1645-1652
ISSN
  • 0002-7863 (ISSN-L)
  • 1520-5126
OpenAlex
W2577348619
Cited by
278
References
69
Citations by year
2026: 10 · 2025: 17 · 2024: 35 · 2023: 27 · 2022: 33 · 2021: 26 · 2020: 30 · 2019: 42 · 2018: 37 · 2017: 21
FWCI
12.80
Type
journal article
Language
en
Open access
closed
Locations
  • Journal of the American Chemical Society (publishedVersion)
  • PubMed (publishedVersion)
Funders
National Science Foundation (NSF-CHE 1607092)
Topics
  • Physical Sciences › Materials Science › Biomaterials › biodegradable polymer synthesis and properties
  • Physical Sciences › Chemical Engineering › Process Chemistry and Technology › Carbon dioxide utilization in catalysis
  • Physical Sciences › Chemistry › Organic Chemistry › Advanced Polymer Synthesis and Characterization
Keywords
ring-opening polymerization, living polymerization, deprotonation, aliphatic polyesters, polycarbonate, lactide, δ-valerolactone, ε-caprolactone, cyclic carbonates, catalyst reactivity, molecular weight distribution, biodegradable polymers

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