One electron more, One electron less. What does it change? Activations Induced by electron Transfer. The electron, an activating messenger.

Transition‐Metal‐Free Homocoupling of Organomagnesium Compounds

“…Since 1 a, generated from 1 and Na in THF, did not react with 1-naphthylmagnesium bromide, a mechanism in which the arylmagnesium reagents are oxidized by 1 a can be ruled out. [21] The oxidation of the organomagnesium reagents does not yield a significant amount of free radicals as only traces of byproducts, which emerge from the abstraction of HC from THF, are detected by GC-MS analysis of the crude reaction mixtures. Complete retention of the configuration of the CÀC double bonds in the coupling of alkenylmagnesium reagents (Scheme 5) also indicates that free radicals are not involved in this homocoupling reaction.…”

New sonochemiluminescence involving solvated electron in Ce(III)/Ce(IV) solutions

“…Hydrogen atom and carbon-centered free radicals • CH 2 OH, • CH 2 CH 2 OH and • C(CH 3 ) 3 are also strong reducing agents formed by ultrasonic treatment of ethylene glycol solutions. The redox potentials of atom H and radicals • CH 2 OH, • C(CH 3 ) 3 are –2.3 V [12] , –0.24 V and –2.1 V [20] respectively, and generally for hydrocarbon radicals of various nature not exceed –2.0 V [21] . Although the reduction of tetravalent cerium ion (reaction (7) ) by atom H (which has the highest reducing ability among the known radical intermediates of ethylene glycol sonolysis) is exothermic, the SCL generation via reaction (7) is unlikely, as in aqueous acidic solutions, where H is the main reducing agent instead of e aq .…”

Übergangsmetall‐freie Homokupplungen von Organomagnesiumverbindungen

“…Die Reaktion von 1 ( c =1.25×10 −5 M ) mit 1‐Naphthylmagnesiumbromid ( c =0.042 M ) verlief ebenfalls unter unmessbar schneller Bildung von 1 a , das innerhalb von 3 s verschwand, d. h. viel schneller als im entsprechenden Experiment mit Mesitylmagnesiumchlorid (Abbildung 1). Weil das aus 1 und Na in THF erzeugte Radikal 1 a nicht mit 1‐Naphthylmagnesiumbromid reagierte, kann ein Mechanismus, bei dem die Magnesiumreagentien durch 1 a oxidiert werden, ausgeschlossen werden 21…”