Selective Visible Light Aerobic Photocatalytic Oxygenation of Alkanes to the Corresponding Carbonyl Compounds

Miriam Somekh, Alexander M. Khenkin, Adi Herman, Ronny Neumann

Research output: Contribution to journalArticle

Abstract

The aerobic, selective oxygenation of alkanes via C-H bond activation is an important research challenge. Photocatalysis offers the potential for the introduction of additional concepts for such reactions. Visible light photoactive semiconductors such as bismuth oxyhalides (BiOX, X = Cl and Br) used in this research typically oxidize organic compounds through photocatalyzed formation of strongly oxidizing holes. The reactive oxygen species formed react with organic compounds in one-electron processes, leading to radical intermediates and nonselective oxidation. Such oxidation reactions generally lead to total oxidation. Here, impregnation of BiOX with a polyoxometalate, H5PV2Mo10O40, as a strong electron acceptor changed the reactivity of BiOX, leading to Mars-van Krevelen-type reactivity, that is, photoactivated oxygen donation from BiOX to the organic substrate followed by reoxidation by O2 and catalysis. This conclusion was supported by mechanistic studies involving isotope labeling studies. In this way, ethane was selectively oxidized to acetaldehyde in a flow reactor with a turnover number (24 h) of 415.

Original languageEnglish
Pages (from-to)8819-8824
Number of pages6
JournalACS Catalysis
DOIs
Publication statusAccepted/In press - Jan 1 2019

Fingerprint

Carbonyl compounds
Alkanes
Oxygenation
Paraffins
Organic compounds
Oxidation
Bismuth
Ethane
Oxygen
Acetaldehyde
Electrons
Photocatalysis
Impregnation
Isotopes
Labeling
Catalysis
Reactive Oxygen Species
Chemical activation
Semiconductor materials
Substrates

Keywords

  • bismuth oxide
  • C-H bond activation
  • oxygen transfer
  • photocatalysis
  • polyoxometalate
  • semiconductor

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)

Cite this

Selective Visible Light Aerobic Photocatalytic Oxygenation of Alkanes to the Corresponding Carbonyl Compounds. / Somekh, Miriam; Khenkin, Alexander M.; Herman, Adi; Neumann, Ronny.

In: ACS Catalysis, 01.01.2019, p. 8819-8824.

Research output: Contribution to journalArticle

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