Title
Origin of the selectivity in the gold-mediated oxidation of benzyl alcohol
Date Issued
01 August 2012
Access level
metadata only access
Resource Type
journal article
Author(s)
Harvard University
Abstract
Benzyl alcohol has received substantial attention as a probe molecule to test the selectivity and efficiency of novel metallic gold catalysts. Herein, the mechanisms of benzyl alcohol oxidation on a gold surface covered with atomic oxygen are elucidated; the results show direct correspondence to the reaction on gold-based catalysts. The selective, partial oxidation of benzyl alcohol to benzaldehyde is achieved with low oxygen surface concentrations and takes place through dehydrogenation of the alcohol to form benzaldehyde via a benzyloxy (C 6H 5-CH 2O) intermediate. While in this case atomic oxygen plays solely a dehydrogenating role, at higher concentrations it leads to the formation of intermediates from benzaldehyde, producing benzoic acid and CO 2. Facile ester (benzyl benzoate) formation also occurs at low oxygen concentrations, which indicates that benzoic acid is not a precursor of further oxidation of the ester; instead, the ester is produced by the coupling of adsorbed benzyloxy and benzaldehyde. Key to the high selectivity seen at low oxygen concentrations is the fact that the production of the aldehyde (and esters) is kinetically favored over the production of benzoic acid. © 2012 Elsevier B.V. All rights reserved.
Start page
1129
End page
1134
Volume
606
Issue
15-16
Language
English
OCDE Knowledge area
Química física
Física atómica, molecular y química
Subjects
Scopus EID
2-s2.0-84861846279
Source
Surface Science
ISSN of the container
00396028
Sponsor(s)
Funding text
R.J.M. and J.C.F.R.-R. gratefully acknowledge the support of the National Science Foundation for this research ( NSF CHE 0952790 ). C.M.F. gratefully acknowledges support of the U.S. Department of Energy , Basic Energy Sciences, grant no. FG02-84-ER13289 . Dr. B. Xu is acknowledged for valuable discussions.
Sources of information:
Directorio de Producción Científica
Scopus