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Corresponding Author

Yi-tao LONG(ytlong@ecust.edu.cn)

Abstract

A widely held concept in electrochemistry is that truly elementary electron-transfer reactions always involve the exchange of one electron, therefore, an overall process involving a change of n electrons must involve n distinct electron-transfer steps. It is highly desirable to resolve multiple-step electron transfer reactions into each electron transfer step. The electrochemical behaviors of coenzyme Q0 and methylene-bridged Bis-coenzyme Q0 were investigated by cyclic voltammetry and square wave voltammetry in nonaqueous dichloromethane containing 0.15 mol·L-1 Bu4NClO4 as the supporting electrolyte. The redox reaction of coenzyme Q0 is well described as two chemically reversible one-electron reduction processes. Bis-coenzyme Q0 exhibits three redox waves in voltammetric experiment, as two bridged coenzyme Q0 units show strong intramolecular electron communication. Experimental data were curve fitted with a Gaussian and Lorentzian mixed product function after subtracting the Shirley background. Results show that four-electron reduction of Bis-coenzyme Q0 is preceded by stepwise pathways, defining as four successive, mono-electronic electron-transfer steps.

Graphical Abstract

Keywords

coenzyme Q0, electron communication, square-wave voltammetry, multi-electron transfer, mono-electronic discrimination

Publication Date

2014-12-28

Online Available Date

2014-06-28

Revised Date

2014-06-23

Received Date

2014-04-29

References

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