Shell Cross-Linked Micelles as Nanoreactors for Enantioselective Three-Step Tandem Catalysis

Michael Kuepfert, Aaron E. Cohen, Olivia Cullen, Marcus Weck

Research output: Contribution to journalArticle

Abstract

Functionalized amphiphilic poly(2-oxazoline)-based triblock copolymers that assemble into shell cross-linked micelles (SCMs) are described. These micelles permit the site isolation of three incompatible catalysts through compartmentalization, thereby enabling three-step non-orthogonal tandem processes in one pot. In particular, the acid-catalyzed ketal hydrolysis to prochiral ketones proceeded in the hydrophilic corona, followed by the Rh-catalyzed asymmetric transfer hydrogenation to enantio-enriched alcohols in the cross-linked shell, and nucleophilic base-catalyzed acylation in the hydrophobic core. The catalysts are positioned in close proximity on a single micelle support to take advantage of the intramicellar substrate diffusion, yet they are sufficiently spaced apart from each other in physically distinct microenvironments. These compartmentalized micelles are substrate selective and, on a basic level, mimic compartmentalized catalytic architectures found in nature.

Original languageEnglish (US)
JournalChemistry - A European Journal
DOIs
StateAccepted/In press - Jan 1 2018

Fingerprint

Nanoreactors
Micelles
Catalysis
Acylation
Catalysts
Substrates
Ketones
Block copolymers
Hydrogenation
Hydrolysis
Alcohols
Acids

Keywords

  • micelles
  • poly(2-oxazoline)
  • site isolation
  • supported catalysts
  • tandem reaction

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Cite this

Shell Cross-Linked Micelles as Nanoreactors for Enantioselective Three-Step Tandem Catalysis. / Kuepfert, Michael; Cohen, Aaron E.; Cullen, Olivia; Weck, Marcus.

In: Chemistry - A European Journal, 01.01.2018.

Research output: Contribution to journalArticle

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