Heterogeneously Catalyzed Oxidation Reactions Using ... - CHEC

CHAPTER 2
amount of transition metal. Thus, metal dispersions etc. will not be taken into account as these data
are only rarely available. Especially in oxidation catalysis, the meaning of a TOF as a microkinetic
description of chemical processes at the active site is limited since the nature of the active site is
often unknown and, even more, many oxidation reactions are at the origin of a radical autoxidation
which was merely induced by the transition metal catalyst. Thus, the TOF will function primarily as a
performance comparison. TOFs presenting essentially a reaction rate are highly dependent on the
experimental conditions, varying greatly for the same reaction when measured at high or low
conversion. Thus, the respective tables will not only give TOFs but also the conversions at which
these were obtained.
2.3.1 Alcohol oxidation
Scheme 2‐2: Schematic overview over the covered oxidation reactions.
The oxidation of alcohols with molecular oxygen has been intensively studied in the recent years with
a great interest in gold catalysis and is described extensively in a number of reviews [5, 6, 95]. The
strength of gold catalysts compared to e.g. Pt group members is the high selectivity to the
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