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COMMUNICATION
Journal Name
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DOI: 10.1039/C9CC00928K
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) of organic hydrides is critical for determining the pathway of
electrochemical hydride generation. A detailed analysis of the
factors that determine radical stability (and correspondingly its
basicity) demonstrates how structural modification can tune
the hydride regeneration mechanism. In contrast, the different
hydride generation pathways (EEP vs. EPE) do not affect the
overall potential required for the complete regeneration, due
to the opposing effects that radical stability plays on
electrochemical potentials and pKa values. Thus, despite its
identical thermodynamic requirements, the EPE mechanism
observed in benzimidazoles is likely more efficient due to the
suppression of undesired radical dimerization. This work
provides the groundwork for a more effective use of organic
hydrides as catalyts.
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This work was supported by the ACS Petroleum Research
Fund (PRF; Grant 54436-ND4) and Kuwait University Fellowship.
The computational work was achieved with the help of the
Advanced Cyberinfrastructure for Education and Research
(ACER) center at the University of Illinois at Chicago.
Conflicts of interest
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Glusac, J. Am. Chem. Soc., 2018, 140, 4569-4579; (b) S. Ilic, A. Alherz,
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12. The appearance of the irreversible peak at -1.5 V is discussed in
ESI Section E2.
There are no conflicts to declare.
Notes and references
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(conjugate base) must undergo a more drastic structural change.
16. The ideal reduction potential for the hydride regeneration (R+ +
2e- + H+ -> RH) was calculated using the hydricity GH- 45 kcal/mol
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4 | J. Name., 2012, 00, 1-3
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