A novel neutral organic electron donor with record half-wave potential

Abstract

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n‐Dopants Based on Dimers of Benzimidazoline Radicals: Structures and Mechanism of Redox Reactions

“…The estimated E eff values are similar to the potentials of the most strongly reducing neutral purely organic compound isolated to date (–1.95 V for the two-electron reduction product of a 2,2'-(pyrrole-2,5-diyl)-bis(4-aminopyridinium) derivative in DMF). [26] …”

Boron as a Powerful Reductant: Synthesis of a Stable Boron‐Centered Radical‐Anion Radical‐Cation Pair

“…[8,18] It should also be emphasized here that diborene 4 thus shows one of the most negative redox potentials observed for any neutral organic molecule to date. [19] As À salt 5 in 68 % yield as a yellow crystalline solid (Scheme 1). The unusual high reduction potential of 4 is further illustrated by the reaction of 4 with MesBC 4 Ph 4 (1), which also allowed for the isolation of the stable boron-centered radical-anion radical-cation pair 6 in 89 % yield as a pink solid.…”

Bor‐Radikalkationen durch Oxidation elektronenreicher Diborene

“…[10,12] Diese stark negativen Reduktionspotentiale sind besonders für Borspezies bemerkenswert und verdeutlichen erneut den Elektronenreichtum des B=B-Bindungssystems. [13] Es sollte zudem hervorgehoben werden, dass es sich hier um sehr seltene, Bor-zentrierte Radikalkationen handelt, [14] von denen unserem Wissen nach nur ein weiteres Beispiel in der Literatur bekannt ist (Bertrand et al). [15] Auffällig ist hier auch der große Unterschied von 0.5 V zwischen den Reduktionspotentialen von 1 und 4, wobei das NHC-substituierte Diboren 1 ein sehr viel stärkeres Reduktionsmittel als sein Phosphananalogon 4 ist .…”