Oxidation saturated

By pulse radiolysis of nitrous oxide-saturated aqueous solutions of ferricyanide (2 X 10 " M) and various alcohols (0.1 M), Adams and Willson " were able to obtain absolute rate coefficients for the ferricyanide oxidation of the radicals derived from the alcohols by attack of the solvent irradiation product, OH-. 

Chromyl chloride also oxidizes saturated hydrocarbons. For example, it oxidizes isobutane to tert-butyl chloride ... 

Part of the mystique surrounding the often assumed high reactivity of dioxiranes stems from the observation that dioxiranes such as methyl(trifluoromethyl)dioxirane (TFDO) are capable of oxidizing saturated hydrocarbons to their alcohols at relatively low temperatures in high yields and with impressive stereoselectivities (equation 8). 

Several attempts have been made, especially in recent years, to oxidize saturated to unsaturated azlactones. 64 The oxidation of saturated azlactone 13 with DDQ or o-chloranil in the presence of collidine as a weak base affords the unsaturated azlactone 14 in 40-50% yield (Scheme 5). Breitholle and Stammer 65 reported the preparation of unsaturated azlactone 16 by dehydrobromination of the bromopseudoazlactone 15 (Scheme 5). The pseudoazlactones derived from Ala and Abu tend to dibrominate, but careful reaction conditions allowed their isolation in acceptable yields. 65 This procedure is applicable to the preparation of derivatives of AAla, AAbu, AVal, and ALeu. 66 ... 

Andrews J, Martin-Bertram El, Elagen U (1984) SI nuclease-sensitive sites in yeast DNA an assay for radiation-induced base damage. Int J Radiat Biol 45 497-504 Antoku S (1983) Radiosensitization and radioprotection of E. coli by thiourea in nitrous oxide saturated suspensions. Int J Radiat Biol 43 451-458... 

Brine (NaCl) solution, removal of colloidal iron oxides Saturated NaCl solution... 

Pentavalent derivatives of triphenylbismuth such as p,-oxobis(chlorotriplienylbismudi) (1) and triphe-nylbismuth carbonate (2) have been developed recently as oxidizing agents which cleave a-glycols into the corresponding carbonyl derivatives (equation 1). Aldehydic products do not undergo further oxidation. Reagent (1) also oxidizes saturated ilcohols as well as allylic and benzylic alcohols, whereas (2) selectively oxidizes allylic alcohols in the presence of saturated alcohols. ... 

Oxidation (saturated with oxygen) 10mg/2mL saturated with bubbled oxygen in amber volumetric flasks. 1, 2, and 3 days... 

Nitrous oxide saturation in surface waters of the Bay of Bengal is relatively smaller, averaging 125% (range 89-214%). The modest supersaturation, presumably caused by the strong thermohaline stratification, supports a lower flux to the atmosphere (0.04-0.12 Tg N2O year ) from the Bay of Bengal than that from the Arabian Sea (Naqvi et al., 1994). 

The oxidation of cholesteryl esters and low-density lipoproteins by free radicals has been reviewed.The use of bis(pentafluorophenyl)borinic acid as a strong Lewis acid allows efficient Oppenauer oxidation of allylic and benzylic alcohols using BfrCHO as oxidant. Saturated alcohols were only slowly oxidized and this allowed selective conversion of allylic alcohols in the presence of saturated alcohols. 

The anionic complex M2 [IrCl6] (M = Na and K) are commercially available and have been used as outer-sphere single-electron oxidants in mechanistic studies of the cleavage of metal-carbon bonds [218]. The isostructural oxidant [PtCle] is also known, especially its ability to oxidize saturated hydrocarbon by electrophilic C-H activation (inner-sphere two-electron oxidant) [219]. 

Ceric ammonium nitrate or ceric sulfate is used to oxidize saturated and unsaturated secondary alcohols to ketones. The ceric salts are used only in catalytic amounts with sodium bromate as a reoxidant (equation 241) [741]. 

In basic solutions ascorbate is apparently oxidized preferentially by the electron transfer process, which goes to completion in less than 2 fts after termination of the electron pulse (see Structure I). In nitrous-oxide-saturated acid solutions (pH 3.0-4.5), A and two other species which were shown to be OH-radical adducts were observed (37), thus confirming earlier observations (18,19,23, 25). The ascorbate radical anion was identified by its doublet of triplets spectrum that maintains its line position from pH 13 to 1. One OH-radical adduct (IV) shows a doublet, the lines of which start to shift below pH 3.0 it has a pK near 2.0, a decay period of about 100 fxs, and probably does not lead to formation of A". The other OH-radical adduct (II) is formed by addition of the OH radical to the C2 position its ESR parameters are = 24.4 0.0002 G and g == 2.0031 0.0002. Time growth studies suggest that this radical adduct converts to the ascorbate anion radical (III) with r 15 fxs, and accounts for 50% of the A signal intensity 40 fxS after termination of the electron pulse. The formation of the three radicals can be summarized as shown in Scheme 1. 

Calorimetric experiments, presented in Section III, A have demonstrated that during the decomposition of small quantities of nitrous oxide at 200°, nitrogen is evolved to the gas phase and that oxygen remains in the adsorbed state. It is therefore reasonable to suppose that decomposition at 250° of nitrous oxide saturating the surface also produces, at the beginning of the reaction process, adsorbed oxygen species. 

The thermodynamics of the Hall-Heroult cell have recently been reexamined by Haupin [16] and by Haupin and Kvande [17]. In the latter paper, inert anodes producing oxygen are also treated. Among the useful results presented is a correlation for the activity of alumina in the electrolyte versus the relative oxide saturation (ROS), Fig. 5. 

Barium Oxide saturated 2S - 90 9 0.3 98.2 BF Gpdd. TempRite pipe... 

An example of the micro-direct methanol fuel cell (p-DMFC) is illustrated in Eig. 3.1. The cell is equipped with two parallel micro channels to supply fuel (CH OH/H SO /H O) and oxidant (saturated 0,/H SO,/H O) [16-18]. At the... 

Topper and Stetten s work involved (1) the reaction of n-glucose-l-d in ordinary water saturated with calcium hydroxide, and (2) the reaction of D-glucose in deuterium oxide saturated with calcium hydroxide-d2. These isomerizations were carried out at both 25° and 35°. In the experiments with D-glucose-l-d at 35°, the n-mannose isolated (as the phenylhydrazone) contained 44 % of the deuterium in the starting substance, all of which was retained at Cl, whereas the n-fructose isolated (as the phenylosazone) retained 94% of the deuterium. A similar result (100% retention of deuterium) was reported for the n-fructose isolated from the reaction at 25°. These figures for n-fructose were based on the assumption that 50 % of the... 

In very rare cases in which photoionization is the only photoprocess, the absorption observed in a nitrous oxide-saturated solution will be that of the cation radical. However, generally, other processes such as intersystem crossing also occur in parallel. In the presence of oxygen, the hydrated electron and the triplet will be scavenged at diffusion-controlled rates, and the absorption observed in the oxygenated solution will be due to the cation radical. Under these conditions, the cation radical spectrum is easily determined. The molar absorption coefficient of the cation radical can also be calculated using the hydrated electron as an internal standard. The molar absorption coefficient for sulphacetamide cation radical was determined in this manner (Land et al 1982) and later confirmed by pulse radiolysis (see Section 12.2.2.6). 

However, hydroxyl radicals are very reactive and known to react with aromatic compounds not only by electron abstraction but also by adding to the ring. Well-established, one-electron oxidizing radicals such as Br2 and N3, formed by pulsing a nitrous oxide saturated solution of potassium bromide or sodium azide, are used to produce cation radicals of the drug molecules. For example, the reactions that take place when a nitrous oxide aqueous solution of lO2 M potassium bromide in the presence of 10 4 M chlorpromazine (C1P) is subjected to pulse radiolysis (Asmus et al., 1979 Davies et al., 1979) are given below ... 

Similarly, the hydroxyl radicals and hydrogen atoms can be scavenged with t-butanol, leaving the hydrated electron to react with the compound to produce its anion radical. MQ anion radical was produced by pulsing a nitrogen-saturated aqueous solution of MQ in the presence of t-butanol (Navaratnam et al., 2000). Another one-electron reductant, C02" , is formed by pulsing a nitrous oxide-saturated solution of sodium formate ... 

Nitrous oxide-saturated solutions of styrene and a-methylstyrene also give sharp peaks at about 305 and 320 m/x, after pulse radiolysis. These resemble the characteristic double peaks of benzyl at 306 and 317 m/x (16). The peaks are therefore attributed mainly to adducts of OH radicals at the / -position in the vinyl group, to give radicals resembling benzyl—e.g.,... 

HO rapidly oxidizes saturated organic compounds via H atom abstraction,... 

Amines caimot undergo the substitution and elimination reactions that alkyl halides undergo, because the leaving groups of amines are too basic. Protonated amines also cannot undergo the reactions that protonated alcohols and protonated ethers undergo. Amines are easily oxidized. Saturated heterocycles containing five or more atoms have physical and chemical properties typical of acyclic compounds that contain the same heteroatom. 

P450 enzymes that oxidize saturated fatty acids, arachidonic acid, and leukotriene (Section 5.5). It may also play a role in the alterations of oxidative metabolism observed in individuals treated with ethynyl sterols such as gestodene and 17a-EE . ... 

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