In-situ EPR Studies of Reaction Pathways in Titania Photocatalyst-Promoted Alkylation of Alkenes

Shona Rhydderch, Russell F. Howe

Research output: Contribution to journalArticle

2 Citations (Scopus)
4 Downloads (Pure)

Abstract

In situ EPR spectroscopy at cryogenic temperatures has been used to observe and identify paramagnetic species produced when titania is irradiated in the presence of reactants used in the photocatalytic alkylation of maleimide with t-butyl carboxylic acid or phenoxyacetic acid. It is shown that maleimide acts as an acceptor of conduction band electrons. Valence band holes oxidise t-butyl carboxylic acid to the t-butyl radical and phenoxyacetic acid to the phenoxyacetic acid radical cation. In the presence of maleimide, the phenoxymethyl radical is formed from phenoxyacetic acid. The relevance of these observations to the mechanisms of titania photocatalyst-promoted alkylation of alkenes is discussed.
Original languageEnglish
Pages (from-to)4055-4070
Number of pages16
JournalMolecules
Volume20
Issue number3
Early online date3 Mar 2015
DOIs
Publication statusPublished - 3 Mar 2015

Fingerprint

Titania
alkylation
Alkylation
Alkenes
Photocatalysts
alkenes
Paramagnetic resonance
acids
Carboxylic Acids
carboxylic acids
titanium
cryogenic temperature
Valence bands
Conduction bands
Cryogenics
Cations
Spectrum Analysis
conduction bands
Spectroscopy
Electrons

Keywords

  • EPR spectroscopy
  • titania
  • photocatalysis
  • alkene alkylation

Cite this

In-situ EPR Studies of Reaction Pathways in Titania Photocatalyst-Promoted Alkylation of Alkenes. / Rhydderch, Shona; Howe, Russell F.

In: Molecules, Vol. 20, No. 3, 03.03.2015, p. 4055-4070.

Research output: Contribution to journalArticle

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