Letters: May 2022

Electrode synthesis

I was delighted to read the article on organic electrosynthesis. It is a subject that I agree has been somewhat overlooked in recent years and is long overdue for a revival.

When I was involved in this field in the late 1970s with the Southampton University group, we were impressed by the possibilities of fine control, versatility, cleanliness and freedom from spent reagent in the work-up. These advantages were not lost on our industrial contacts. However, our use of expensive precious metal electrodes was seen as a serious drawback for scale-up to industrial plant size. Accountants have a strong presence in commerce.

The question of whether a more economical, less noble electrode material would suffice was rarely considered at the time, so focused were we on the range of chemical transformations now possible.

Whereas for some electrochemical transformations platinum may well be the only viable choice, it is very likely other reactions may be more versatile in their electrode options. After all, the Monsanto Baizer process for industrial adiponitrile production traditionally uses a lead cathode.

I feel that it would be most useful to consider alternative electrode materials as part of electrosynthetic studies. I have been excited to read of the large range of newer electrode materials being reported in recent literature for environmental applications, for example for carbon dioxide reduction. There would be merit in including some in the list of electrode candidates alongside the obvious list of noble metals.

I have the impression that this is a branch of chemistry for which we have only just begun to unlock its possibilities, and I commend it to any group tempted to explore it.

David Coe MRSC
St Neots, UK