Controlled Interruption of Electrochemical Nitrite Reduction for Switchable NH2OH and Formamide Synthesis
Xingmiao Huang1,2, Shijie Xie3, Yangfan Li4
1Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing National Laboratory for Molecular Sciences, Beijing, P. R. China.
Angewandte Chemie (International Ed. in English)
|May 1, 2026
Summary
This study introduces a new electrochemical strategy to control nitrogen product distribution. By adjusting pH and CO, researchers precisely produced formamide or hydroxylamine from nitrite reduction.
Area of Science:
- Electrochemistry
- Catalysis
- Materials Science
Background:
- Electrochemical nitrite reduction typically yields ammonia.
- Controlling product selectivity in nitrogen electroreduction is challenging.
Purpose of the Study:
- To develop a strategy for precise control over electrochemical nitrite reduction products.
- To achieve selective synthesis of formamide and hydroxylamine.
Main Methods:
- Utilized a reduction-interruption strategy on a Bi@C catalyst.
- Cooperative regulation of pH and CO to program reaction pathways.
- Investigated mechanistic insights into interfacial water and active hydrogen generation.
Main Results:
- Achieved 80.2% Faradaic efficiency for formamide production under alkaline conditions with CO.
- Reached 79.1% Faradaic efficiency for hydroxylamine at near-neutral conditions.
- Demonstrated pH-dependent control over reduction depth and CO capture.
Conclusions:
- The developed strategy enables programmable multi-electron electrocatalysis.
- Interfacial structural control and molecular trapping expand nitrogen electrosynthesis beyond ammonia.
- Offers a generalizable route to accessing metastable nitrogen intermediates.
Related Concept Videos
01:13meta-Directing Deactivators: –NO2, –CN, –CHO, –CO2R, –COR, –CO2H
4.6K
All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for...
4.6K
01:29Preparation of Amines: Reduction of Oximes and Nitro Compounds
3.7K
Oximes can be reduced to primary amines using catalytic hydrogenation, hydride reduction, or sodium metal reduction. The reduction of aliphatic and aromatic nitro compounds to primary amines takes place by either catalytic hydrogenation or by using active metals like Fe, Zn, and Sn in the presence of an acid.
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
3.7K
01:19Diazonium Group Substitution: –OH and –H
1.9K
Nitrous acid, a weak acid, is prepared in situ via the reaction of sodium nitrite with a strong acid under cold conditions. This nitrous acid prepared in situ reacts with primary arylamines to form arenediazonium salts. Such reactions are known as diazotization reactions. As shown in Figure 1, the formation of arenediazonium salts begins with the decomposition of nitrous acid in an acidic solution to give nitrosonium ions.
1.9K
01:202° Amines to N-Nitrosamines: Reaction with NaNO2
3.9K
Secondary amines react with nitrous acid to form N-nitrosamines, as depicted in Figure 1. Nitrous acid, a weak and unstable acid, is formed in situ from an aqueous solution of sodium nitrite and strong acids, such as hydrochloric acid or sulfuric acid, in cold conditions. In the presence of an acid, the nitrous acid gets protonated. The subsequent loss of water results in the formation of the electrophile known as nitrosonium ion.
3.9K
01:38Preparation of Amines: Reductive Amination of Aldehydes and Ketones
3.2K
Carbonyl compounds and primary amines undergo reductive amination first to produce imines, followed by secondary amines in the same reaction mixture, using selective reducing agents like sodium cyanoborohydride or sodium triacetoxyborohydride. Reductive amination produces different degrees of substitution of amines depending on the starting amine substrate.
3.2K
01:27Phase I Reactions: Reductive Reactions
801
Phase I biotransformation reductive reactions are chemical processes that modify drugs by introducing or revealing polar functional groups via reduction. Enzymes called reductases catalyze these reactions, playing a pivotal role in drug metabolism by transforming lipophilic drugs into more polar, water-soluble metabolites for easy excretion. An essential type of reductive reaction is the carbonyl group reduction, where aldehydes and ketones are reduced to alcohols. An example is the...
801