Oxidative dehydrogenations with

The data presented above showed that the oxidative dehydrogenation reactions of the various alkanes share many common features. Thus it is tempting to discuss selectivity for alkane oxidative dehydrogenation with a common scheme. The reaction scheme for ethane oxidation [Eqs. (5)-(7)] provides a useful basis for such a discussion. It shows that the primary reaction of alkane oxidation can take on three different pathways depending on the reaction temperature (Scheme I). The first step in all three pathways is breaking a C—H bond, which is the rate-limiting step. The three pathways are described below. 

Propano-linked macrocyclic complexes (69) have been shown to undergo oxidative dehydrogenation with ease under mild conditions (equation 27).157>162 This reaction occurs for nickel(II), copper(II) and cobalt(II) complexes and leads to cobalt(III) dibenzocorromins , which are simple models of the vitamin B12 coenzyme nucleus.163 Macrocyclic complexes containing this ligand chromophore had already been prepared by a direct metal template method (Scheme 29).164 165 However, the oxidative dehydrogenation route offers greater experimental certainty and variety. 

Oxidative dehydrogenation with formation of quinonoid structures... 

In order to assess the synthetic potential of enzymatic oxidations for organosilicon chemistry, the (hydroxyalkyl)silanes 95, 97 and 99 have been studied for their oxidation (dehydrogenation) with horse liver alcohol dehydrogenase (HLADH E.C. l.l.l.l)79. For this purpose, these compounds were incubated with HLADH in a TRIS-HC1 buffer/THF system in the presence of NAD+. As monitored spectrophotometrically (increase of absorbance of the NADH formed), the (2-hydroxyethyl)silane 97 and the (3-hydroxypropyl)silane 99 were better substrates for HLADH than ethanol, whereas the related (hydroxymethyl)silane 95 was not a substrate under the experimental conditions used. Interestingly, the corresponding carbon analogue 101 was found to be accepted by HLADH. On the other hand, the (2-hydroxyethyl)silane 97 was found to be a better... 

Cortez, G.G. Banares, M.A. A Raman Spectroscopy Study of Alumina-Supported Vanadium Oxide Catalyst During Propane Oxidative Dehydrogenation with Online Activity Measurement /. Catal. 2002, 209, 197-201. 

Croomine is a major alkaloid of the roots and rhizomes of Croomia heterosepala. Its structure (10) has been settled by its chemical reactions and spectroscopic properties, and confirmed by X-ray diffraction analysis of its methiodide. On mild oxidation (dehydrogenation) with silver oxide, the alkaloid affords the corresponding pyrrole.8... 

The above discussed were several aspects of ethylbenzene conjugated oxidation (dehydrogenation) with hydrogen peroxide. This reaction was studied in detail in many investigations... 

Comparison of overall reactions (5.13)—(5.16) and (5.17)—(5.20) shows that (5.13)— (5.16) transform from common dehydrogenation to oxidative dehydrogenation with hydrogen peroxide participation. Such transformation of the target, secondary reaction in the reaction system becomes possible owing to the induction effect of the primary reaction of H202 dissociation. 

In the presence of copper(I) chloride in pyridine N-benzylidene-o-phenylenediamines 20 undergo catalytic oxidative dehydrogenation with 0 to afford 2-arylbenzimidazoles 21 or 2,2 -diaryl-1,1 -... 

Kaddouri, A., Mazzocchia, C., and Tempesti, E. Propane and isobutane oxidative dehydrogenation with K, Ca and P-doped a- and 8-nickel molybdate catalysts. Appl. Catal. A Gen. 1998,169, L3. 

An efficient one-pot procedure for the quinazoline derivatives 123 is outlined in Scheme 27. The cyclocondensation of aminobenzamides 121 with aldehydes 122 in the presence of P-TSOH.H2O produced quinazolinones which upon oxidative dehydrogenation with DIB delivered N-alkoxy quinazolinones in good yields. Additionally, the present method enables to prepare quinazolines containing drug molecules, for example, a sedative agent me aqualone 124 [43]. 

About 65% butene conversion is achieved at more than 95% selectivity." Phil-hps also developed the 0-X-D process, which operated under similar conditions. Both processes use fixed beds of catalyst. Oxidative dehydrogenation with metal oxide catalysts involves a redox mechanism and the catalyst used should not be reduced irreversibly dining the cycle. 

Oxidative dehydrogenation with oxygen or air of N-heterocycles including dihydroacridine was developed using Pt nanowire catalyst and was performed under 1 bar of oxygen in methanol at 40 °C in quantitative yield (2013CCC2183). 

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