Electrochemistry in Magnetic Fields

Abstract

Developing new strategies to advance the fundamental understanding of electrochemistry is crucial to mitigating multiple contemporary technological challenges. In this regard, magnetoelectrochemistry offers many strategic advantages in controlling and understanding electrochemical reactions that might be tricky to regulate in conventional electrochemical fields. However, the topic is highly interdisciplinary, combining concepts from electrochemistry, hydrodynamics, and magnetism with experimental outcomes that are sometimes unexpected. In this Review, we survey recent advances in using a magnetic field in different electrochemical applications organized by the effect of the generated forces on fundamental electrochemical principles and focus on how the magnetic field leads to the observed results. Finally, we discuss the challenges that remain to be addressed to establish robust applications capable of meeting present needs.

Metal-catalysed C–H bond activation and borylation

“…Employing their previously 164 developed method for the ortho selective borylation of anisole with a yttrium catalyst, Xu and co-workers recently reported a strategy for the selective C2 borylation of pyridine derivatives (Scheme 56). 165 The authors demonstrated that a large number of substrates underwent selective C2 borylation, which can be further converted into their hydroxy derivatives using oxone as the oxidising agent. The mechanistic investigations revealed that the reaction proceeded via C–H activation as the rate-determining step.…”

Selecting an Optimal Faraday Cage To Minimize Noise in Electrochemical Experiments

“…In addition, since most electrode materials are not ferromagnetic (e.g., platinum, gold, carbon), interferance is unlikely to result in significant noise as eddy currents will not be induced in the absence of a relatively strong and dynamic magnetic field. Magnetoelectrochemistry is a relatively new field which uses strong magnetic fields (e.g., >0.5 T) to influence electrochemical processes such as radical generation and corrosion . However, since magnetic fields are generally weak in the absence of a proximal appliance/source (∼10 μT), the contribution to electrochemical noise may be ignored under typical laboratory conditions.…”

“…Magnetoelectrochemistry is a relatively new field which uses strong magnetic fields (e.g., >0.5 T) to influence electrochemical processes such as radical generation and corrosion. 23 However, since magnetic fields are generally weak in the absence of a proximal appliance/source (∼10 μT), 24 the contribution to electrochemical noise may be ignored under typical laboratory conditions.…”

Transition-Metal-Catalyzed Regioselective C–H Borylation of ­Pyridines

“…Inspired by this observation, very recently, our group explored a catalytic ortho-selective C-H borylation of pyridines with pinacolborane (HBpin) by utilization of an yttrocene catalyst Cp* 2 Y(THF)CH 2 SiMe 3 (Cp* = C 5 Me 5 ), providing facile access to a variety of 2-pyridyl boronates with a broad substrate scope and high atom economy. 26 On the grounds of our prior work in 2019 (Scheme 5), a series of rare-earth metallocene complexes were evaluated for reaction of DMAP with HBpin under catalytic conditions. It was found that the rare-earth metal ionic radius plays a pivotal role in selectivity tuning.…”