Oxidative conversion

At low temperatures the SCR reactions dominate and nitrogen oxide conversion increases with increasing temperature. But as temperature increases, the ammonia oxidation reactions become relatively more important. As the temperature increases further, the destmction of ammonia and generation of nitrogen oxides by the oxidation reactions causes overall nitrogen oxide conversion to reach a plateau then decreases with increasing temperatures. Examples are shown in Figure 7 (44). 

Non-oxidative conversion of a tetrahydro-)8-carboline into a 3,4-dihydro derivative has also been described. Dehydration of 1-hydroxymethyl-1,2,3,4-tetrahydro-j8-carboline (146) yielded 1-methyl-3,4-dihydro-j8-carboline (135). Harmaline and l-methyl-3,4-dihydro-j8-carboline-3-carboxylic acid were obtained in an analogous manner. ... 

Oxidative Conversion of Oxaziranes into Nitroso Compounds... 

Allyl alcohol is produced by the catalytic isomerization of propylene oxide at approximately 280°C. The reaction is catalyzed with lithium phosphate. A selectivity around 98% could be obtained at a propylene oxide conversion around 25% ... 

Degradation of the insecticide chlorpyrifos has been examined in solutions of aqueous chlorine in which the primary oxidant is hypochlorous acid/hypochlorite. The final product was 2,3,5-trichloropyrid-2-one produced either directly, or via initial oxidative conversion of the thioate ester by replacement of the sulfur with oxygen (Duirk and Collette 2006). An analogous oxidation was found with diazinon (Zhang and Pehkonen 1999). 

Fig. 3. Nitric Oxide conversion as a function of oxigen inlet concentration on Pt Co M reduced ( ) Co M oxidazed ( ) anfl COjjM reduced ( )samples. NO 1000 ppm, CH. 1000 ppm, balance to 1 atm He, Temperature 450 °C, GHSV 6500 h .

The direct oxidative conversion of primary halides and sulfonates to aldehydes can be carried out by reaction with DMSO under alkaline conditions. Formulate a mechanism for this reaction. 

Complex oxide film is formed in a basic solution, whereas the films described earlier are formed in an acidic solution. Complex oxide conversion coating reactions do not contain either hexavalent or trivalent chromium ions. However, the sealing rinse contains much greater quantities of hexavalent and trivalent chromium ions than do the sealing rinses associated with phosphate conversion coatings and chromate conversion coatings. 

Ravi, V., Mok, Y.S., Rajanikanth, B.S. et al. (2003) Temperature effect on hydrocarbon-enhanced nitric oxide conversion using a dielectric barrier discharge reactor, Fuel Processing Technology 81, 187-99. 

Oxidative conversion of palmatine, berberine, and coptisine to polycarpine, polyberbine, and its analog was described in Section II,B. These products were further transformed to aporphine alkaloids having a phenolic hydroxyl group at C-2 in the bottom ring (55). Hydrolysis with concomitant air oxidation of polyberbine (66) furnished 3,4-dihydrorugosinone, which was further air-oxidized in ethanolic sodium hydroxide to give rise to rugosinone (501) (Scheme 105). Successive reduction of the enamide 68 with lithium aluminum hydride and sodium borohydride afforded a mixture of ( )-norledecorine and (+ )-ledecorine (502). N-Methylation of the former with formaldehyde and sodium borohydride led to the latter. 

The activation of molecular oxygen by copper plays a central role in synthetically useful stoichiometric and catalytic oxidative conversions of organic molecules and in biological systems.4"26... 

Nagao, A, 2004. Oxidative conversion of carotenoids to retinoids and other products. J Nutr 134, 237S-240. 

The temperature resistance of the polysiloxane on the samples was tested by stepwise heating up to 500°C. Whereas the pure hydrolysis product undergoes a complete thermal degradation via oxidative conversion of the CH3-Si groups into HO-Si groups, the polysiloxane persists on the silica sample. This stabilization effect most likely results from the covalent attachment of the methyl-polysiloxane. 

The donor strength is quantitatively evaluated by the energetics of the oxidative conversion of an organic donor (D) to its cation radical (D+ ) as measured in solution by its reversible oxidation potential ( ox)63 (equation 28). 

Figure 11.36 Frequency count for the oxidative conversion of methylcyclohexene of a tungsten-based library.

Figure 11.37 Frequency count for the oxidative conversion of methylcyclohexene of a library based on of W03 stemming from the calcination of (NH3)2W04. The variation of the reaction conditions included a pH variation of the H202 solution, variation of the ratios of catalyst, oxidant and substrate and the reaction temperature. A total of 200 experiments were performed.

FIGURE 4.44 Cytochrome P450-dependent oxidative conversion of cholesterol to progesterone... 

FIGURE 4.83 P450-catalyzed oxidative conversion of the cyano group of pinacidil to the amide. 

Zhang Z, Li Y, Stearns RA, et al. Cytochrome P450 3A4-mediated oxidative conversion of a cyano to an amide group in the metabolism of pinacidil. Biochemistry 2002 41(8) 2712-2718. 

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