Solvent-Free Oxidation of Primary Alcohols to Aldehydes Using Au-Pd/TiO 2 Catalysts

American Association for the Advancement of Science (AAAS) - Tập 311 Số 5759 - Trang 362-365 - 2006
Dan I. Enache1,2, Jennifer K. Edwards1,2, Philip Landon1,2, Benjamín Solsona1,2, Albert F. Carley1,2, Andrew A. Herzing3,1, Masashi Watanabe3,1, Christopher J. Kiely3,1, David W. Knight1,2, Graham J. Hutchings1,2
1Center for Advanced Materials and Nanotechnology, Lehigh University, 5 East Packer Avenue, Bethlehem, PA 18015–3195, USA.
2School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, UK, CF10 3AT,
3Center for Advanced Materials and Nanotechnology, Lehigh University, 5 East Packer Avenue, Bethlehem, PA 18015-3195, USA

Tóm tắt

The oxidation of alcohols to aldehydes with O 2 in place of stoichiometric oxygen donors is a crucial process for the synthesis of fine chemicals. However, the catalysts that have been identified so far are relatively inactive with primary alkyl alcohols. We showed that Au/Pd-TiO 2 catalysts give very high turnover frequencies (up to 270,000 turnovers per hour) for the oxidation of alcohols, including primary alkyl alcohols. The addition of Au to Pd nanocrystals improved the overall selectivity and, using scanning transmission electron microscopy combined with x-ray photoelectron spectroscopy, we showed that the Au-Pd nanocrystals were made up of a Au-rich core with a Pd-rich shell, indicating that the Au electronically influences the catalytic properties of Pd.

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Sponsored by the European Union AURICAT project (contract HPRN-CT-2002-00174) and the Engineering and Physical Sciences Research Council (EPSRC) as part of the ATHENA project co-sponsored by Johnson Matthey as well as by an EPSRC-sponsored program on Speculative Green Chemistry and we thank them for funding this research. We also thank the World Gold Council (through the GROW scheme) and Cardiff University (AA Reed studentship) for providing support for J.K.E. D.I.E. thanks the Crystal Faraday Partnership for funding. Finally C.J.K. M.A.W. and A.A.H. gratefully acknowledge NSF funding through the Materials Research Science and Engineering Center (NSF grants DMR-0079996 DMR-0304738 and DMR-0320906).

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American Association for the Advancement of Science (AAAS)

Tập 311 Số 5759

362-365

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