Bifunctional Polymer Architectures for Cooperative Catalysis: Tunable Acid-Base Polymers for Aldol Condensation

Caroline B. Hoyt, Li Chen Lee, Aaron E. Cohen, Marcus Weck, Christopher W. Jones

Research output: Contribution to journalArticle

Abstract

Cooperative catalysts combining weak acids and basic amines have been utilized to effectively catalyze aldol and related coupling reactions under mild conditions. Most cooperative chemical catalysts for the aldol reaction have been based on silica-supported amines. In this work, an alternate approach is demonstrated whereby cooperative amine/acid interactions are tailored through the implementation of polymeric supports. By using linear poly(styrene) supports, this work demonstrates that the design and spacing of monomer units plays an essential role in the cooperativity of the acid-base sites in the aldol condensation. The monomer sequence of each polymer catalyst dramatically affects the catalytic activity, with a random copolymer displaying optimal cooperativity between the acid and base, and block copolymers drastically reducing catalyst activity. Trends established in the silica-supported systems, such as use of stronger acid monomers demonstrating reduced activity, are verified and extended to these polymer-supported systems. Overall, this first generation polymer-supported system is not as efficient as the optimal silica-supported catalysts developed over the last decade, with the polymers studied here being poorly soluble, leading to inefficient use of the amine sites.

Original languageEnglish (US)
JournalChemCatChem
DOIs
StateAccepted/In press - 2016

Fingerprint

Catalysis
catalysis
Condensation
Polymers
condensation
Amines
amines
catalysts
acids
Acids
Silicon Dioxide
polymers
monomers
Monomers
Silica
silicon dioxide
Catalysts
Catalyst activity
Styrene
block copolymers

Keywords

  • Aldol
  • Bifunctional catalysts
  • Cooperative catalysis
  • Polymers
  • Supported catalysts

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry
  • Organic Chemistry
  • Inorganic Chemistry

Cite this

Bifunctional Polymer Architectures for Cooperative Catalysis : Tunable Acid-Base Polymers for Aldol Condensation. / Hoyt, Caroline B.; Lee, Li Chen; Cohen, Aaron E.; Weck, Marcus; Jones, Christopher W.

In: ChemCatChem, 2016.

Research output: Contribution to journalArticle

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AU - Weck, Marcus

AU - Jones, Christopher W.

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