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Oxime ethers are attractive compounds in medicinal scaffolds due to the biological and pharmaceutical properties, however, the crucial and widespread step of industrial oxime formation using explosive hydroxylamine (NH2OH) is insecure and troublesome. Herein, we present a convenient method of oxime ether synthesis in a one‐pot tandem electrochemical system using magnesium based metal‐organic framework‐derived magnesium oxide anchoring in self‐supporting carbon nanofiber membrane catalyst (MgO‐SCM), the in situ produced NH2OH from nitrogen oxides electrocatalytic reduction coupled with aldehyde to produce 4‐cyanobenzaldoxime with a selectivity of 93 % and Faraday efficiency up to 65.1 %, which further reacted with benzyl bromide to directly give oxime ether precipitate with a purity of 97 % by convenient filtering separation. The high efficiency was attributed to the ultrafine MgO nanoparticles in MgO‐SCM, effectively inhibiting hydrogen evolution reaction and accelerating the production of NH2OH, which rapidly attacked carbonyl of aldehydes to form oximes, but hardly crossed the hydrogenation barrier of forming amines, thus leading to a high yield of oxime ether when coupling benzyl bromide nucleophilic reaction. This work highlights the importance of kinetic control in complex electrosynthetic organonitrogen system and demonstrates a green and safe alternative method for synthesis of organic nitrogen drug molecules. [ABSTRACT FROM AUTHOR]

Pyridine oximes produced from aldehyde or ketone with hydroxylamine (NH2OH) have been widely applied in pharmaceutics, enzymatic and sterilization. However, the important raw material NH2OH exhibits corrosive and unstable properties, leading to substantial energy consumption during storage and transportation. Herein, this work presents a novel method for directly synthesizing highly valuable pyridine oximes using in situ generated NH2OH from electrocatalytic NO reduction with well‐design nanofiber membranes (Al‐NFM) derived from NH2‐MIL‐53(Al). Particularly, 2‐pyridinealdoxime, the precursor of antidote pralidoxime (2‐PAM) for nerve agents suffering from scarcity and high cost, was achieved with a Faraday efficiency up to 49.8 % and a yield of 92.1 %, attributing to the high selectivity of NH2OH production on Al‐NFM, further easily reacted with iodomethane to produce 2‐PAM. This study proposes a creative approach, having wide universality for synthesizing pyridine and other oximes with a range of functional groups, which not only facilitates the conversion of exhaust gas (NO) and waste water (NO2−) into valuable chemicals especially NH2OH production and in situ utilization through electrochemistry, but also holds significant potential for synthesis of neuro detoxifying drugs to humanity security. [ABSTRACT FROM AUTHOR]

How to transfer industrial exhaust gases of nitrogen oxides into high‐values product is significantly important and challenging. Herein, we demonstrate an innovative method for artificial synthesis of essential α‐amino acids from nitric oxide (NO) by reacting with α‐keto acids through electrocatalytic process with atomically dispersed Fe supported on N‐doped carbon matrix (AD‐Fe/NC) as the catalyst. A yield of valine with 32.1 μmol mgcat−1 is delivered at −0.6 V vs. reversible hydrogen electrode, corresponding a selectivity of 11.3 %. In situ X‐ray absorption fine structure and synchrotron radiation infrared spectroscopy analyses show that NO as nitrogen source converted to hydroxylamine that promptly nucleophilic attacked on the electrophilic carbon center of α‐keto acid to form oxime and subsequent reductive hydrogenation occurred on the way to amino acid. Over 6 kinds of α‐amino acids have been successfully synthesized and gaseous nitrogen source can be also replaced by liquid nitrogen source (NO3−). Our findings not only provide a creative method for converting nitrogen oxides into high‐valued products, which is of epoch‐making significance towards artificial synthesis of amino acids, but also benefit in deploying near‐zero‐emission technologies for global environmental and economic development. [ABSTRACT FROM AUTHOR]