Copper(II) Porphyrin as Biomimetic Catalyst for Oxidation of Trimethylphenol

Abstract:

Synthetic metalloporphyrins have long been recognized either as functional models or mimics of the cytochrome P-450 enzymes and they are versatile compounds with potential use in drug delivery, catalysis and electronics. In the present study, the metalloporphyrin, (meso-tetra-(p-sulfonatophenyl)-porphyrinato)copper, CuTSPP was synthesized in the reaction between free-base porphyrin, meso-tetra (p-sulfonatophenyl)porphyrin, H₂TSPP and copper(II) acetate monohydrate. The materials were characterized using Fourier Transform Infrared Spectroscopy (FTIR), Ultraviolet-Visible (UV-Vis) Spectroscopy, Proton Nuclear Magnetic Resonance (¹H NMR) Spectroscopy and Mass Spectrometry (MS) analysis. The FTIR spectra of both free-base porphyrin and CuTSPP showed the appearance of three pronounced bands indicating the presence of the salt form (R-SO₃Na) of the sulfonic acid group. Characterization of CuTSPP by UV-Vis spectroscopy confirmed that the insertion of copper into the free-base porphyrin was successful by the appearance of the Soret band and Q bands. The catalytic activity of CuTSPP was tested in the oxidation of 2,3,6-trimethylphenol (TMP) at 60 °C using hydrogen peroxide (H₂O₂) as oxidant. The reaction parameters including the reaction temperature and time have been optimized. The only product obtained by means of TMP oxidation with H₂O₂ using CuTSSP is 2,3,5-trimethylbenzoquinone (TMBQ), an important precursor for the industrial production of Vitamin E.

• Periodical: Materials Science Forum (Volume 846)
• Pages: 706-711
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.846.706
• Online since: March 2016
• Authors: Nurliana Roslan, Salasiah Endud*, Zainab Ramli, Hendrik O. Lintang
• Keywords: 2,3,5-Trimethylbenzoquinone, 2,3,6-Trimethylphenol, Biomimetic Models, Metalloporphyrin, Oxidation

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