Boric Acid‐Coordinated Electrooxidation of Glycerol to Hydroxypyruvic Acid and Coupling With Hydroxylamine Reduction to Serine

ABSTRACT The electrocatalytic glycerol oxidation represents a potential route for upgrading bulk chemicals to value‐added products such as amino acids. Nonetheless, the rapid cleavage of carbon‐carbon (C─C) bonds during electro‐oxidation of glycerol tends to form low‐value C 1 chemicals, limiting the selectivity of amino acids. Regulating the selectivity of hydroxyl (─OH) oxidation of glycerol and coupling with hydroxylamine reduction may provide the capability of tuning the reaction pathways. Herein, we report a polyol‐boric acid protection strategy to selectively oxidize specific ─OH groups in glycerol to convert into hydroxypyruvic acid, utilizing boric acid coordination to protect two ─OH groups while leaving the uncoordinated one available for oxidation. Using β ‐Ni(OH) 2 as the catalyst, a 47.5% Faraday efficiency of hydroxypyruvic acid was achieved in a glycerol‐containing boric acid buffer solution. Furthermore, when coupled with hydroxylamine reduction, the integrated electrochemical cell allowed the selective production of serine, with a Faraday efficiency of 31.3% and a glycerol conversion rate of 37.0%. Our work represents an attractive approach to glycerol transformation and C─N coupling for the electrochemical synthesis of amino acids.