CYCLOHEXANE FUNCTIONALIZATION
VI. ACKNOWLEDGMENTS
283
For example, based on total selectivities for the oxidation
products, only 30 to 50% of the consumed TBHP is needed.
These data suggest that there is a dual pathway involved
where decomposition of TBHP is not useful for oxidation of
cyclohexane. As more catalyst is added, there is a tendency
to favor the decomposition reaction pathway. In a similar
way, efficiency of TBHP decreases from around 40% to less
than 31% as the reaction temperature increases from 60 to
100ꢂC for all the doped catalysts.
We thank the Department of Energy, Office of Basic Energy Science,
Division of Chemical Science, and Texaco, Inc. for support of this research.
We thank the editor, Professor W. N. Delgass, for several helpful sugges-
tions regarding experiments that were carried out and interpretation of
the data.
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The other initial pathway may involve radicals such as
formation of hydroxyl and RO (reaction 1b) by the inter-
action of TBHP with catalyst. The reaction is believed to
occur on the basis of product selectivities and the nature of
peroxide.
The initial activation of cyclohexane is proposed to oc-
cur in two separate pathways as shown in reaction 2a of
Scheme 1 which involves formation of a cyclohexyl radical
and H2O. The other activation as shown in reaction 2b of
the Scheme 1 involves formation of cyclohexyl radical and
alcohol.
Product formation may be governed by the combination
of radicals as shown in reaction 3a and 3b of Scheme 1.
The two products (A and CHP) may serve as intermediates
to form other products such as those shown in reaction 3c
(K) and 3d (P). The data of Fig. 6 show a disappearance
of CHP with concomitant formation of K. These data sug-
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