Oxygen electron donors

Table 1 Geometric parameters for halogen bonded complexes with nitrogen and oxygen electron donors... 

A fuel is a substance capable of burning the CH bonds (electrons acceptor). An oxidant is a substance that helps in burning, providing oxygen (electrons donor). Only when the oxidizer and fuel are intimately mixed in an appropriate proportion can an exothermic chemical reaction be initiated that generates substantial heat. The temperature reached when the reaction starts in the oxidizer and fuel solution, is called the ignition temperature. 

The negatively charged oxygen substituent is a powerful electron donor to the carbonyl group Resonance m carboxylate anions is more effective than resonance m carboxylic acids acyl chlorides anhydrides thioesters esters and amides... 

Solvating extractants contain one or more electron donor atoms, usually oxygen, which can supplant or partially supplant the water which is attached to the metal ions. Perhaps the best known example of such an extractant is tri-( -butyl) phosphate) [126-73-8] (TBP), which forms... 

The heteroaromatic compounds can be divided into two broad groups, called n-excessive and n-deficient, depending on whether the heteroatom acts as an electron donor or an electron acceptor. Furan, pyrrole, thiophene, and other heterocyclics incorporating an oxygen, nitrogen, or sulfur atom that contributes two n electrons are in the rr-exeessive group. This classification is suggested by resonance structures and confirmed by various MO methods. ... 

Biostimulatioo Any process that increases the rates of biological degradation, usually by the addition of nutrients,oxygen, or other electron donors and acceptors so as to increase the number of indigenous microorganisms available for degradation of contaminants. 

Finally, examine the highest-occupied molecular orbital (HOMO) of phenoxide anion. Is the HOMO the best electron-donor orbital Is the orbital localized primarily on oxygen or on carbon Is the observed product consistent with orbital control Explain your answers. 

When equimolar quantities of 80a and its dication 110 are combined in acetonitrile, single electron transfer occurs and the coproportionation product was obtained (95TL2741).Tliis deeply red-colored, air-sensitive radical cation 111 showed a strong ESR signal (g = 2.0034). On the other hand, the excellent electron donor 80a could be prepared by electrolytic reduction starting from 110. It was necessary to carry out the reduction with scrupulous exclusion of oxygen. Tlius, the electrolysis of 110 at -1.10 V initially gave rise to an intense red color, which was presumably due to the formation of 111. Upon further reduction, the red color faded and the tetraaza-fulvalene 80a was isolated at a 62% yield (Scheme 45). 

Although Ru(bipy)2+ alone will not split water into hydrogen and oxygen, it has been accomplished with Ru(bipy)2+ using various catalysts or radical carriers. Perhaps the most studied system for the photoreduction of water involves using methyl viologen as the quencher, EDTA as an electron donor (decomposed in the reaction) and colloidal platinum as a redox catalyst (Figure 1.19). 

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