Oxidation production from

The synthesis of (23) illustrates how a six-membered ring may bo used to control even more remote chiral centres. Reverse Michael disconnection leaves enone (24), an oxidation product from allylic alcohol (25). The double bond can come from elimination on bromohydrln (26) and hence from (27). 

The main oxidation product from dibenzyl ether is benzaldehyde (up to 80% yield) with smaller amounts of benzyl alcohol and benzoic acid. The rates of oxidation are only slightly affected by major stereochemical changes, and it is considered that an outer-sphere oxidation of the ether is followed by radical breakdown, viz. 

Formation of oxidation products from 3-carotene, such as epoxides and apocarotenals, occurs only at extreme conditions of combined temperature, time, or pressure. 

We have summarized below recent results concerning spectroscopic / flow reactor investigations of hydrocarbons partial and total oxidation on different transition metal oxide catalysts. The aim of this study is to have more information on the mechanisms of the catalytic activity of transition metal oxides, to better establish selective and total oxidation ways at the catalyst surface, and to search for partial oxidation products from light alkane conversion. 

FIGURE 16.13 Mass spectrum of the isolated compound 24-norursa-3,12-dien-ll-one (compound 11) (Rf 0.55), an oxidized product from the pyrolysate of B. serrata. 

Nelan, D. R. Robeson, C. D. The oxidation product from a-tocopherol and potassium ferricyanide and its reaction with ascorbic and hydrochloric acids. J. Am. Chem. Soc. 1962, 84, 2963-2965. 

Derivitization reactions have previously been employed to extend the sensitivity and resolution of IR, ultraviolet and X-ray photo-electron spectroscopy (7-13). Yet no proposed method has the range to accommodate the major oxidation products from polyolefins. As part of an ongoing study of polymer oxidation and stabilization, we discuss here a series of reactions with small, reactive gas molecules. The products from these reactions can be rapidly identified and quantified by IR. Some of these reactions are new, others have already been described in the literature, although their products have not always been fully identified. 

Je KH, Han AR, Lee HT, Mar W, Seo EK. The inhibitory principle of lipopolysaccha-ride-induced nitric oxide production from Inula britannica var. chinensis. Arch Pharm Res 2005 27 83-85. 

Carail, M. and C. Caris-Veyrat (2006). Carotenoid oxidation products From villain to saviour Pure Appl. Chem. 78(8) 1493-1503. 

Tetrahydrofuran has been reported to exhibit an absorption maximum at 280 nm (52,56), but several workers have shown that this band is not produced by the purified solvent (30,41,57). Oxidation products from THF have been invoked in order to account for the appearance of the 280-nm band in PVC films that are solvent-cast from THF in air (57. 581. However, in some reported cases (56,59), this band was undoubtedly produced, at least in part, by a phenolic antioxidant (2.6-di-tert-butyl-p-cresol)(59) in the solvent. Since certain -alkylphenols have now been shown to be powerful photosensitizers for the dehydrochlorination of PVC (60), it is clear that antioxidant photosensitization might well have been responsible for some of the effects attributed previously (56) to THF alone. On the other hand, enhanced rates of photodegradation under air have also been observed for PVC films cast from purified THF (57), a result which has been ascribed to radical formation during the photooxidation of residual solvent (57,61). Rabek et al. (61) have shown that this photooxidation produces a-HOO-THF, a-HO-THF, and y-butyro-lactone, and they have found that the hydroperoxide product is an effective sensitizer for the photodehydrochlorination of PVC at X = 254 nm (61). 

Diamino-1,2,4-thiadiazoles 66, also known as Hector s bases, are the oxidation products from iV-arylthioureas 65 a large number of examples of this type of reaction are known. Typical oxidants that give good yields are acidic hydrogen peroxide, nitrous acid, and iron(m) chloride (Equation 20) <1996CHEC-II(4)307>. 

Bodin, A., et al., Identification and allergenic activity of hydroxyaldehydes — anew type of oxidation product from an ethoxylated non-ionic surfactant, Contact Dermatitis, 44, 207, 2001. 

In isocitrate, there is a CHOH group that is available for oxidation via the coenzyme NAD+ and the enzyme isocitrate dehydrogenase. NADH will then be reoxidized via oxidative phosphorylation, and lead to ATP synthesis. The oxidation product from isocitrate is oxalosuccinate, a -ketoacid that easily... 

Hou, C.T., Propylene oxide production from propylene by immobilized whole cells of Methylosinus sp. CRL 31 in a gas-solid bioreactor, Appl. Microbiol. Biotech., 19 (1984) 1-4. 

Oxidation products from tetrahydropapaveroline with potassium ferricyanide were reinvestigated by Mak and Brossi 21), who confirmed structure 28 for the initial product. Air oxidation of 29 gave after acetylation a product with the same physical properties reported by Harley-Mason, but its mass spectrum showed a parent ion at m e 900 and molecular composition C48H40N2O16, suggesting it to be a dehydro dimer of 12. The H-NMR spectrum of the dimer showed that the double bonds at the 5,6 positions were intact. The point of dimerization was determined by comparing the multiplicities of carbons in the C-NMR spectra of the dimer and dibenzopyrrocoline models. For monomeric compounds the peak ascribed to C-12 in compound 11 was a triplet and a doublet in 12, but a singlet in the dimer. Thus, the products from oxidation of 28 had structures 31 and 32 rather than 29 and 30, respectively. 

Although B jO 3 is the expected oxidation product from boron in a room temperature situation, the lower oxide, BO, appears to... 

The two intermediates depicted above differ fundamentally from each other. The COx-producing intermediate has a direct metal-carbon (M-R) bond whereas the C2-producing intermediate has a metal-oxygen-carbon (M-O-R) bond. From known organic decomposition pathways, the formation of selective oxidation products from the M-O-R intermediate is likely. An a-H elimination produces acetaldehyde and a P-H elimination produces ethylene. 

At the lowest concentrations of 2-propanol, 10"2 M, there is reasonable agreement between calculated and experimental results. These results then are consistent with the assumption that acetone is the only oxidation product from the radical produced from 2-propanol in aqueous solution containing oxygen. It has similarly been shown (23) that acetaldehyde is the only organic oxidation product in the radiation-induced oxidation of aqueous ethanol. However, our experiments indicate that in... 

Based partly on UV-vis absorption but mostly on surface-enhanced Raman scattering (SERS) data, the electrochemical oxidation product from 9-hydroxyellipticine (9-OH-E) 13a at Pt and Ag electrodes and that from A -methyl-9-hydroxyellipticinium cation (NMHE) 13b at those electrodes and also by horseradish peroxidase-H2O2 were studied and their structures identified <1996JRS539>. The products, 9-oxoellipticine (9-oxo-E) 14a from 9-OH-E and A -methyl-9-oxoellipticinium cation (NMOE) 14b from NMHE both have quinone-imine structures readily identified from the vibrational analysis of their SERS spectra. 

Sequential Oxidation Products from Tropospheric Isoprene Chemistry MACR and MPAN at a NOt-Rich Forest Environment in the Southeastern United States, J. Geophys. Res., 103, 22463-22471 (1998). 

Nouaime, G S. B. Bertman, C. Seaver, D. Elyea, H. Huang, P. B. Shepson, T. K. Starn, D. D. Riemer, R. G. Zika, and K. Olszyna, Sequential Oxidation Products from Tropospheric Isoprene Chemistry MACR and MPAN at a NO,-Rich Forest Environment in the Southeastern United States, J. Geophys. Res., 103, 22463-22471 (1998). 

Problem 13.38 Give the hydroboration-oxidation product from (a) cydohexene, (6) cir-2-phenyl-2-butene, (c) trarw-2-phenyl-2-butene. 

The trapped nitric oxide becomes a stable nitroxide radical that is the same chemical moiety present in most common spin-trapping reagents. Nitric oxide production from activated macrophages has been directly assayed by this method (Korth et al., 1992). 

X. NITRIC OXIDE PRODUCTION FROM NITRITE BY ENTERIC AND... 

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