Single-electron reducing

In this titration the analyte is oxidized from Fe + to Fe +, and the titrant is reduced from CryOy to Cr +. Oxidation of Fe + requires only a single electron. Reducing CryOy, in which chromium is in the +6 oxidation state, requires a total of six electrons. Conservation of electrons for the redox reaction, therefore, requires that... 

Sodium serves as single electron reducing agent and EtOH is the proton donor. If no proton donor is available, dimerization will take place, as the Acyloin Condensation. 

Most POM reductions (chemical, photochemical or electrochemical) result in the production of heteropoly blue species that involve reduction of MVI to Mv, M = Mo or W, and some coupling of spins (frequently antiferromagnetic coupling in poly anions with an even number of electrons). Single-electron-reduced species are by far the most common, but two- and four-electron species are not uncommon, and there are several examples of heteropoly blue compounds with six or more electrons. Despite the implication of the name heteropoly blue, there are several examples of reduced isopolyanions (isopoly compounds) that have similar properties. The structural and electronic properties of these reduced complexes are addressed in older reviews cited in the Introduction (Section 4.11.1) and also in the accompanying chapter by M. T. Pope (Chapter 4.10). 

The trifluoroacetamide group is one of the more useful amides because of the ease in which it may he removed under mildly basic conditions. Otherwise, it is stable to acidic conditions such as TFA and single electron reducing agents such as Na/an-thracene, but is reduced with hydride reducing agents. 

The single-electron reduced state, the semiquinone, is thermodynamically unstable in aqueous solution, with only 5% present in equimolar mixtures of fully oxidized and fully reduced flavins. However, protein interactions alter the stability of the semiquinone markedly - some stabilizing it, others suppressing it. The... 

The reaction of Cu (aq) thus prepared can he studied (41-43) as long as Cr +(aq) does not interfere with the study. Natiu ally, other strong single-electron reducing agents can replace Cr ", for example, V (aq) (44). 

The redox potential of these complexes transforms Cud) complexes to be reasonably good single-electron reducing... 

The study of the problem of H2 evolution from water has shown that it is promising to use rhodium complexes with polyamines (PEI, AN-221) as active and stable catalysts of H2 evolution from water in the presence of strong single-electron reduc-tants such as and Cr q [283]. Polymeric rhodium completes are highly stable. For ecample, in a special test, a catalyst based on Rh-AN-221 maintained its original activity during more than 6500 catalytic cycles per 1 g of rhodium, while the activated species preserved its catalytic activity for a year. 

Single-electron reducing reagents are applicable to afford phosphanylidene carbenoids. 2,2-Dichlorophosphaethene (2a) was allowed to react with lithium... 

With the first factor equal to V2, only the single-electron reduced matrix element for the orbital operators remains to be calculated. With some effort the following expression may be derived ... 

And the use of metal-arenes as single-electron reducing agents for TiCla allows the McMurry reaction between aromatic and aliphatic aldehydes and ketones to proceed at room temperature. ... 

---