Isopropanol, oxidation

This is entirely analogous to the Westheimer mechanism for isopropanol oxidation (Section 2.2.3). 

These results do not prove that the ester is an essential intermediate in aqueous solution even though it is present, but the result with the hindred triterpene is convincing In this case the esterification step, which is normally fast, has become rate-determining and the disappearance of the isotope effect must mean that C-H cleavage occurs after the formation of the ester and not independently of it. The generality of this result is apparent from the stopped-flow investigation of isopropanol oxidation ... 

Finally, in analogy with organic chemistry, "polymerization" of metal-metal multiple bonds may lead to clusters as illustrated in eqs. 12 and 13. To date, the only definitely characterized oligomerization reaction of this type has been reported by McCarley et al. (8j(eq. 14), although Chisholm et al. ( ) have observed that Mo2(0Et)6 dimerizes to a tetranuclear complex of unknown structure and that the 0-H bond of isopropanol oxidatively adds to the WeW bond of W2(i-Pr0)6 to give a tetranuclear complex with an "open" as opposed to a closed, or cluster, structure (10). Also, some evidence has been presented that Cp2Mo2(C0)it may form unstable tetrahedrane intermediates (eq. 12) (. 

Isopropanol oxidation process isopropanol is oxidized with air to acetone and H2O2 at 90 to 140 C and 15 to 20 bar and the reaction mixture worked up by distillation. The acetone byproduct must be utilized. 

Copper.—Oxygen Chemistry. The effect of isopropanol oxidation at 400 K on the oxygen content of an initially copper(ii) oxide catalyst has been studied gravimetrically by Volta et During normal running the catalyst was... 

In their study of isopropanol oxidation over copper(ii) oxide, Volta e/a/. found that their kinetic data agreed with an earlier reaction scheme where dis-sociatively adsorbed oxygen is involved in the rate-determining step. The rate of acetone formation (Fac) fitted equation (25) ... 

In another application, recombinant E. coli produced 36.6 g/L ethyl-(R)-4-chloro-3-hydroxybutanoate (99% ee) from 40 g/L ethyl-4-chloro-3-oxo-butanoate[210). Here, the secondary alcohol dehydrogenase served as both synthetic (asymmetric reduction) and regenerating (NADH-regeneration via isopropanol oxidation) enzyme (Fig. 16.2-49). 

Fig. 12. Dependence of the photoassisted rates of carbon monoxide oxidation over Ti02 (upper plots) and of isopropanol oxidation over ZnO (lower plots) on reactant pressure. Observed rate photo-oxidation at each pressure is subdivided, in the manner of eqns. (39) in the text, into a rate Vx displaying a Langmuir—Hinshelwood pressure dependence and another rate, V2, increasing linearly with reactant pressure and consistent with an Eley—Rideal process. Reproduced with permission from refs. 183 and 257.

Zhou W, Wang C, Xu J, Du Y, Yang P (2010) Enhanced electrocatalytic performance for isopropanol oxidation on Pd-Au nanoparticles dispersed on poly(p-phenylene) prepared from biphenyl. Mater Chem Phys 123 390-395... 

Krilov OV, KisUev VF (1981) Adsorption and catalysis on the transition metals and their oxides. Chemistry, Moscow Kroger FA, Vink HJ (1956) Relations between concentrations of imperfections in crystaUine solids. In Seitz F, TumbuU D (eds) Solid state physics, vol 3. Academic, New York, pp 307-435 Kulkami D, Wachs IE (2002) Isopropanol oxidation by pure metal oxide catalysts number of active surface sites and turnover frequencies. Appl Catal A 237 121-137 Kulwicki BM (1991) Humidity sensors. J Am Ceram Soc 74 697-708... 

The most important source of acetone is the Hock process for phenol production. In this process acetone is obtained as stoichiometric coupling product. If acetone needs to be produced deliberately, it can be obtained by oxidative dehydrogenation or dehydrogenation of isopropanol. Oxidative dehydrogenation proceeds at 400-600 °C at silver or copper contacts, direct dehydrogenation is carried out at 300-400 °C using zinc contacts. Alternatively, acetone can also be obtained by a Wacker-Hoechst oxidation of propylene. Acetone is used industrially as solvent. Moreover, the aldol condensate products of acetone (diacetone alcohol) are used as solvents. Acetone is also converted in an add catalyzed reaction with two moles of phenol for the synthesis of bisphenol A. Bisphenol A is an important feedstock for the production of epoxy resins and polycarbonates. 

Kulkami, D. and Wachs, I.E. Isopropanol oxidation hy pure metal oxide catalysts number of active surface sites and turnover frequencies, Catal 2002, 237, 121-137. 

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