Spin trapping of radical intermediates in gas phase catalysis: cyclohexane oxidation over metal oxides.
نویسندگان
چکیده
The formation of radicals in the gas phase oxidation of cyclohexane over metal oxides was studied using spin trapping and EPR spectroscopy; the results confirmed that during the catalytic initiation, the oxygen responsible for the radicals formation originates from the lattice of the metal oxide.
منابع مشابه
Radical intermediates in chloroform reactions over triphenylphosphine-protected Au nanoparticles.
Reactions of chloroform over triphenylphosphine-protected Au nanoparticles have been studied using electron paramagnetic resonance (EPR) spectroscopy and a spin trapping technique. Two competing reactions, abstraction of hydrogen and halogen atoms, were identified. The hydrogen abstraction reaction showed an inverse kinetic isotope effect. Treatment of nanoparticles with oxidizing or reducing r...
متن کاملEnantioselective functionalization of radical intermediates in redox catalysis: copper-catalyzed asymmetric oxytrifluoromethylation of alkenes.
A method for the efficient enantioselective oxytrifluoromethylation of alkenes has been developed using a copper catalyst system. Mechanistic studies are consistent with a metal-catalyzed redox radical addition mechanism, in which a C–O bond is formed via the copper-mediated enantioselective trapping of a prochiral alkyl radical intermediate derived from the initial trifluoromethyl radical addi...
متن کاملCyclohexane oxidation using Au/MgO: an investigation of the reaction mechanism.
The liquid phase oxidation of cyclohexane was undertaken using Au/MgO and the reaction mechanism was investigated by means of continuous wave (CW) EPR spectroscopy employing the spin trapping technique. Activity tests aimed to determine the conversion and selectivity of Au/MgO catalyst showed that Au was capable of selectivity control to cyclohexanol formation up to 70%, but this was accompanie...
متن کاملGas-phase reduction of oxides of nitrogen with CO catalyzed by atomic transition-metal cations.
important reactions occurring in automotive catalytic converters where both reactants are undesirable pollutants. Base-metal oxides, mixed metal-oxide compounds such as perovskites, supported metal catalysts, metal zeolites, and alloys have all been investigated as heterogeneous catalysts for this reaction, which does not occur directly in the gas phase at room temperature to any measurable ext...
متن کاملStatistical Optimization of Liquid Phase Oxidation of Benzyl Alcohol over Efficient Cobalt Promoted Vanadyl Pyrophosphate Catalysts by Box-Behnken Design
Vanadium phosphorus oxides (VPO) has been applied as a heterogeneous catalyst in gas phase oxidation reactions and its application is very limited in liquid phase. In this study a series of cobalt-doped vanadium phosphorus oxides (VPO-Co) catalysts with different loading of Co (0.01-1.0 mol ratio of Co/V) were prepared. Oxidation of benzyl alcohol was studied in the liquid phase over VPO and VP...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Chemical communications
دوره 46 22 شماره
صفحات -
تاریخ انتشار 2010