Highly active and recyclable heterogeneous iridium pincer catalysts for transfer dehydrogenation of alkanes

Zheng Huang, Maurice Brookhart, Alan S Goldman, Sabuj Kundu, Amlan Ray, Susannah L. Scott, Brian C. Vicente

Research output: Contribution to journalArticle

88 Citations (Scopus)

Abstract

Pincer-ligated iridium complexes have proven to be highly effective catalysts for the dehydrogenation and transfer-dehydrogenation of alkanes. Immobilization onto a solid support offers significant potential advantages in the application of such catalysts particularly with respect to catalyst separation and recycling. We describe three approaches toward such immobilization: (i) covalent attachment to a Merrifield resin, (ii) covalent bonding to silica via a pendant alkoxysilane group, and (iii) adsorption on γ-alumina (γ-Al2O3), through basic functional groups on the para-position of the pincer ligand. The simplest of these approaches, adsorption on γ-Al2O3, is also found to be the most effective, yielding catalysts that are robust, recyclable, and comparable to or even more active than the corresponding species in solution. Spectroscopic evidence (NMR, IR) and studies of catalytic activity support the hypothesis that binding occurs at the para-substituent and that this has only a relatively subtle and indirect influence on catalytic behavior.

Original languageEnglish
Pages (from-to)188-206
Number of pages19
JournalAdvanced Synthesis and Catalysis
Volume351
Issue number1-2
DOIs
Publication statusPublished - Jan 2009

Fingerprint

Iridium
Alkanes
Dehydrogenation
Paraffins
Catalysts
Adsorption
Aluminum Oxide
Catalyst supports
Silicon Dioxide
Functional groups
Recycling
Catalyst activity
Alumina
Resins
Ligands
Silica
Nuclear magnetic resonance

Keywords

  • Alkanes
  • Alumina
  • Dehydrogenation
  • Iridium
  • Pincer ligands
  • Supported catalysts

ASJC Scopus subject areas

  • Catalysis
  • Organic Chemistry

Cite this

Highly active and recyclable heterogeneous iridium pincer catalysts for transfer dehydrogenation of alkanes. / Huang, Zheng; Brookhart, Maurice; Goldman, Alan S; Kundu, Sabuj; Ray, Amlan; Scott, Susannah L.; Vicente, Brian C.

In: Advanced Synthesis and Catalysis, Vol. 351, No. 1-2, 01.2009, p. 188-206.

Research output: Contribution to journalArticle

Huang, Zheng ; Brookhart, Maurice ; Goldman, Alan S ; Kundu, Sabuj ; Ray, Amlan ; Scott, Susannah L. ; Vicente, Brian C. / Highly active and recyclable heterogeneous iridium pincer catalysts for transfer dehydrogenation of alkanes. In: Advanced Synthesis and Catalysis. 2009 ; Vol. 351, No. 1-2. pp. 188-206.
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