N -heterocyclic carbene-like catalysis by a metal-organic framework material

Marianne B. Lalonde, Omar K. Farha, Karl A. Scheidt, Joseph T Hupp

Research output: Contribution to journalArticle

85 Citations (Scopus)

Abstract

Metal imidazolates, an important class of constructs in metal-organic framework chemistry, are shown here to be precursors to N-heterocyclic carbene-like catalysts. By using n-butyl lithium to deprotonate tripodal imidazolate framework-1 (TIF-1), N-heterocyclic carbene (NHC) sites can be exposed. These sites are found to be remarkably competent as Brønsted-base-type NHC catalysts. An α,β-unsaturated ketone was converted to the corresponding benzyl ether with benzyl alcohol at a faster rate and in higher yield than with a traditional homogeneous NHC catalyst (1,3-bis-(2,4,6-trimethylphenyl)imidazole)), despite lower overall loading. Varying the size of the alcohol in the conjugate addition reaction yielded no change in reaction rate, even when the size of the alcohol exceeded the diameter of the MOF pores, suggesting that catalysis occurs exclusively on the surface of the MOF crystals, as opposed to within the framework pores.

Original languageEnglish
Pages (from-to)1550-1554
Number of pages5
JournalACS Catalysis
Volume2
Issue number8
DOIs
Publication statusPublished - Aug 3 2012

Fingerprint

Catalysis
Alcohols
Metals
Catalysts
Addition reactions
Benzyl Alcohol
Ketones
Reaction rates
Ethers
Lithium
Ether
Crystals
carbene
Organic Chemistry

Keywords

  • conjugate addition
  • ethers
  • metal organic frameworks
  • N-heterocyclic carbenes

ASJC Scopus subject areas

  • Catalysis

Cite this

N -heterocyclic carbene-like catalysis by a metal-organic framework material. / Lalonde, Marianne B.; Farha, Omar K.; Scheidt, Karl A.; Hupp, Joseph T.

In: ACS Catalysis, Vol. 2, No. 8, 03.08.2012, p. 1550-1554.

Research output: Contribution to journalArticle

Lalonde, Marianne B. ; Farha, Omar K. ; Scheidt, Karl A. ; Hupp, Joseph T. / N -heterocyclic carbene-like catalysis by a metal-organic framework material. In: ACS Catalysis. 2012 ; Vol. 2, No. 8. pp. 1550-1554.
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