Enhanced catalyst performance through compartmentalization exemplified by colloidal L-proline modified microgel catalysts

D. Kleinschmidt, M.S. Fernandes, M. Mork, A.A. Meyer, J. Krischel, M.V. Anakhov, R.A. Gumerov, I.I. Potemkin, M. Rueping, A. Pich*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

16 Citations (Web of Science)

Abstract

Exploring and controlling chemical reactions in compartments opens new platforms for designing bioinspired catalysts and energy-autonomous systems. Aqueous polymer networks or hydrogels serve as a perfect model for biological tissues, allowing systematic investigations of chemical transformations in compartments. Herein, we report the synthesis of a versatile, colloidal microgel catalyst containing covalently bound L-proline as an organocatalyst. The key finding of our work is that the catalytic activity can be tuned by adjusting the distribution of the organocatalyst in the microgel network as well as the properties of the solvent. We demonstrate that L-proline groups integrated into microgels enable the reaction of 4-nitrobenzaldehyde and cyclohexanone in a heterogeneous reaction mixture in which free L-proline is not active. By controlling the localization of the L-proline groups within the microgel network (core or corona), the rate of the aldol reaction in homogenous and heterogeneous reaction mixtures can be modulated. Furthermore, microgels with covalently attached catalysts can be recycled and reused in sequential catalytic runs without deterioration of the catalyst performance in terms of activity and selectivity. The internal structure of the microgel in heterogeneous reaction mixtures was studied by computer simulations. (C) 2019 Elsevier Inc. All rights reserved.
Original languageEnglish
Pages (from-to)76-87
Number of pages12
JournalJournal of Colloid and Interface Science
Volume559
DOIs
Publication statusPublished - 1 Feb 2020

Keywords

  • asymmetric aldol reaction
  • bioinspired
  • cascade
  • computer simulations
  • dissipative particle dynamics (dpd)
  • enantioselective aldol
  • l-proline
  • microgels
  • nanoreactors
  • organocatalysis
  • particles
  • pnipam
  • polymer
  • precipitation polymerization
  • reaction kinetics
  • supported l-proline
  • water
  • PARTICLES
  • SUPPORTED L-PROLINE
  • Microgels
  • ORGANOCATALYSIS
  • CASCADE
  • Organocatalysis
  • Bioinspired
  • ASYMMETRIC ALDOL REACTION
  • Dissipative particle dynamics (DPD)
  • Computer simulations
  • Reaction kinetics
  • WATER
  • PNIPAM
  • NANOREACTORS
  • ENANTIOSELECTIVE ALDOL
  • L-Proline
  • POLYMER
  • Precipitation polymerization

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