Simple electrochemical reduction of nitrones to amines

Abstract

Only electricity is needed for the transformation of nitrones to amines. Such a direct double reduction has not been reported by any sole chemical reagent in a single step process.

Current electrochemical approaches to selective deuteration

“…33 It was suggested that an intermediate benzylic radical was formed by electrochemical reduction of a benzylidene imine and, through examination of a series of controls, that d 6 -DMSO acted as a deuterium source through a deuterium atom transfer (Scheme 8). This is in contrast to a similar study by Rodrigo and Waldvogel, 34 who identified an imine as an intermediate in their electrochemical reduction of nitrones to amines, and proposed a final protonation step in a MeCN/H 2 O solvent (rather than a HAT). Li and Huang here also invoke an oxidation of DMSO to dimethyl sulfone under air; the preference of this over other oxidative processes such as product oxidation to a radical-cation, followed by deprotonation to regenerate the benzylic radical (in a similar fashion to that in Scheme 7b), was indirectly inferred through control reactions where no deuterium incorporation was found when the secondary amine was subjected to similar reaction conditions (Scheme 8b).…”

Chemical‐Reductant‐Free Electrochemical Deuteration Reaction using Deuterium Oxide

“…When a graphite rod was used as the anode, the reaction only gave trance conversion (entry 9). Such an unusual anode effect in a cathodic reduction was also observed recently by Waldvogel and Rodrigo in their work on the electrochemical reduction of nitrones …”

Recent Advances in the Electrochemical Reduction of Substrates Involving N−O Bonds

“…A broad scope of aromatic and heteroaromatic amines, containing a large variety of functional groups, was accessible. The utilization of electric current allowed for the first time the avoidance of two different reagents for this reduction, something mandatory if this transformation were performed with classical chemical reagents …”