Electron transfer in catalysis

Acid Catalysis in Electron Transfer flavin analogue (FI)... 

According to Eq. 6, the value becomes larger with decrease in Aa, i.e., the larger pAa value. In general, the pAa value becomes larger in an aprotic solvent such as MeCN as compared with the value in water, since the solvation energy for proton in an aprotic solvent is much less than that in water [85]. Thus, acid catalysis in electron transfer reactions is expected to be much more efficient in acetonitrile... 

Bronsted acid catalysis in electron transfer reactions can also be applied to catalysis of metal ions in electron transfer reactions, since not only protons but also metal... 

Metal ion catalysis in electron transfer by complexation with radical anions... 

Bronsted acid catalysis in electron transfer described in Section 1.3.1 has also been effective for redox reactions via the electron transfer step. As shown in the case of metal ion-catalyzed hydride transfer reactions (see above), hydride transfer reactions from an NADH analogue to /7-benzoquinones also proceed via Bronsted acid-catalyzed electron transfer [255, 256]. Since NADH and ordinary NADH model compounds are subjected to the acid-catalyzed hydration [98, 257, 258], an acid-stable NADH model compound, 10-methyl-9,10-dihydroacridine (AcrH2), was used as a hydride donor to / -benzoquinone (Eq. 24) ... 

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