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Oxidation potentials table

The difference between dienes reacting according to type A and those according to type B is clearly reflected in their oxidation potentials (Table 5). [Pg.762]

The electrooxidation of organosilicon compounds containing heteroatoms has been investigated extensively and various synthetic applications have been developed. Cooper and Owen studied the oxidation potentials of a series of silyl-substituted amines, phosphines, and sulfides, and observed that silyl substitution at the carbon adjacent to the heteroatom caused a significant decrease in the oxidation potentials (Table 4) [35]. [Pg.65]

Although the oxidation potentials of aldehydes and ketones are generally very high, silyl substitution at the carbonyl carbon results in a significant decrease in the oxidation potential (Table 6) [16] (Sect. 2.3.3). For example, undecanoyl-trimethylsilane exhibits an oxidation wave at the peak potential of 1.45 V. The effect of the silyl-substitution in the oxidation potential of aryl-substituted carbonyl compounds, however, is much smaller [56]. [Pg.74]

The large value of / 59, and its similarity to the reactions of Craq002 + with two other radicals of widely different reduction and oxidation potentials, Table VIII, strongly supports radical coupling as the mechanism for reaction 59. [Pg.43]

Ground state complex formation between t-1 and electron donor molecules has not been reported. The reduction potential of t-1 is substantially larger in absolute value than its oxidation potential (Table 5), thus providing an explanation for the observation of ground state complex formation between t-1 and electron acceptors but not electron donors. [Pg.192]

The fluorescence of 3-t (113-117) and 3-7 (118) is quenched by secondary and tertiary amines. Rate constants for quenching of It by tertiary amines increase with decreasing amine ionization or oxidation potential (Table 11), as expected for the formation of a charge-transfer stabilized exciplex in which the amine serves as the electron donor. Electron transfer quenching in nonpolar solvent is calculated to be exothermic for amines with E 2 < 1 34 V. Thus, it is not surprising that secondary and tertiary amines quench 3-t with rate constants which approach or even exceed the rate of diffusion. The inefficient quenching of It and 3-7 by primary amines is consistent with their higher oxidation potentials. [Pg.203]

The identity of the radical ions formed upon steady-state radiation of DNA in low-temperature glasses has been established by means of electron paramagnetic resonance (EPR) spectroscopy [53]. EPR analysis indicates that electrons and holes are localized on a single nucleobase rather than being delocalized over several stacked bases at low temperatures. Radical ion formation is presumed to occur randomly at all four nucleosides. However, EPR studies establish that the electron holes are localized predominately on guanine, which has the lowest gas phase ionization potential and solution oxidation potential (Tables 1 and 3). Yan et al. [54]... [Pg.1780]

Bernstein et al. [82] have recently investigated the dynamics of collisional quenching of triplet Ceo by silyl derivatives of guanine and 8-oxoguanine in benzo-nitrile solution. The observed rates are 3.3 x 10 M s and 1.1 x 10 M s , respectively, in accord with an electron transfer mechanism in which the silylated nucleobase of lower oxidation potential (Table 3) is the better electron donor. [Pg.1789]

The action of the hypohalites is generally far more drastic in alkaline solution than in acid or neutral media. As the values of the oxidation potentials (Table I) do not predict this result, the effect may be attributed in part to the action of alkali on the sugars. The oxidation is not con-... [Pg.156]

A large amount of data exists for the oxidation of thiols using monomeric MPc catalysts compared to porphyrins. Table 7.2. As Table 7.2 shows the potential for the oxidation of cysteine is highly dependent on pH being lower in basic media. The study of the oxidation of 2-ME has mainly been conducted in basic media, and this species is readily oxidized on MPc modified electrodes, as judged by the low oxidation potential. Table 7.2. In general the potentials for the oxidation of thiols is dependent on the MPc catalysts and the electrolyte as was the case with porphyrin catalysts. [Pg.323]

Electrochemically [Fe(9S3)2] shows a reversible one-electron oxidation at a highly oxidizing potential (Table 2). Oxidation of [Fe(9S3)2] either by Pb02... [Pg.22]


See other pages where Oxidation potentials table is mentioned: [Pg.64]    [Pg.707]    [Pg.257]    [Pg.185]    [Pg.314]    [Pg.51]    [Pg.100]    [Pg.1791]    [Pg.169]    [Pg.286]    [Pg.59]    [Pg.64]    [Pg.2066]   
See also in sourсe #XX -- [ Pg.479 ]




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Oxidation potential

Oxidation-reduction potentials general table

Oxidation-reduction potentials table

Oxidizing potential

Tables oxides

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