Production Of Amines Research Articles

Regioselective Surface Assembly of Mesoporous Carbon on Zeolites Creating Anisotropic Wettability for Biphasic Interface Catalysis

The anisotropic surface functionalization of microporous zeolites with mesoporous materials into hierarchically porous heterostructures with distinctive physical and chemical properties is expected to significantly extend their applicability to catalysis. However, the precise control of the surface chemistry of zeolite crystals through site-specific interconnection with mesoporous materials remains a grand challenge. Here, we report a regioselective surface assembly strategy for the region-specific growth of mesoporous polymer/carbon on zeolite nanocrystals. The approach enables controllable regioselective surface deposition of mesoporous polydopamine on the edges, curved surfaces, or/and flat surfaces of the silicalite-1 nanocrystals into exotic hierarchical nanostructures with diverse surface geometries. Upon carbonization, their derived heterostructures with anisotropic surface wettability show amphiphilic properties. As a proof of concept, Pt nanoparticle-encapsulated silicalite-1/mesoporous carbon nanocomposites are tested to be interface-active for forming Pickering emulsions. Significantly, the catalysts show superior catalytic performance in shape-selective hydrogenation of various nitroarenes in a series of biphasic tandem catalytic reactions, giving ∼100% yield of corresponding amine products. The results pave a path toward rational construction of high levels of surface structural complexity in hierarchically porous heterostructures for specific physical and chemical characteristics in diverse applications.

Mechanistic kinetic modeling of the rhodium-catalyzed tandem hydroaminomethylation of 1-decene in a thermomorphic solvent system

For a more resource-efficient production of amines the homogeneously catalyzed tandem hydroaminomethylation reaction is of large relevance. The kinetics of the sulfoxantphos‑rhodium-catalyzed hydroaminomethylation of 1-decene were studied exploiting a thermomorphic solvent system. Focus was a mechanistic kinetic description of the enamine hydrogenation as the final step in the tandem reaction. Based on proposing a catalytic cycle and applying the Christiansen mathematics, a mechanistic rate model was derived and parameterized. The mechanistic model was able to describe the experimental observations in a broad range of operation conditions including pressure and temperature perturbations providing the basis for process design and optimization.

Ring-opening reactions of phosphoramidate heterocycles

We present protocols for the conversion of phosphoramidate heterocycles into 1,3-chloroamines and 1,3-aminoalcohols. For the formation of chloroamines, our optimized protocol involves heating the phosphoramidate starting material with 4 equivalents of HCl in a dioxane/toluene solvent mixture. The substituents on the phosphoramidate starting material have a profound influence on product formation. Phosphoramidates with a variety of aza-heterocyclic substituents engage, but those containing a 5-chloro-8-quinolinol arm are most competent for 1,3-chloroamine formation. Furthermore, only the phosphoramidate cis diastereomers allow for 1,3-chloroamine formation. X-ray crystallography studies coupled with DFT analysis provide a basis for the stark difference in reactivity between the cis and trans diastereomers. Amino-alcohol products form by heating phosphoramidate heterocycles with aqueous HF in toluene. Here, there is no diastereomeric preference or a requirement for an aza-heterocyclic arm. Based on a substrate survey, both reactions tolerate a broad range of substitution patterns and functional groups. This work establishes that phosphoramidates are competent synthons for interesting amine products and further increases the prominence of tethered aza-Wacker technology.

Catalytic Homologation-Allylboration Sequence for Diastereo- and Enantioselective Synthesis of Densely Functionalized β-Fluorohydrins with Tertiary Fluoride Stereocenters.

Homologation of trisubstituted fluoroalkenes followed by allylboration of aldehyde, ketone and imine substrates is suitable for synthesis of β-fluorohydrin and amine products. In the presence of (R)-iodo-BINOL catalyst enantioselectivities up to 99% can be achieved by formation of a single stereoisomer with adjacent stereocenters, of which one is a tertiary C-F center.

Catalytic Homologation‐Allylboration Sequence for Diastereo‐ and Enantioselective Synthesis of Densely Functionalized β‐Fluorohydrins with Tertiary Fluoride Stereocenters

AbstractHomologation of trisubstituted fluoroalkenes followed by allylboration of aldehyde, ketone and imine substrates is suitable for synthesis of β‐fluorohydrin and amine products. In the presence of (R)‐iodo‐BINOL catalyst enantioselectivities up to 99 % can be achieved by formation of a single stereoisomer with adjacent stereocenters, of which one is a tertiary C−F center.

Probiotic Properties, Safety Assessment, and Aroma-Generating Attributes of Some Lactic Acid Bacteria Isolated from Iranian Traditional Cheese

Artisanal cheeses are known as the source of beneficial lactic acid bacteria (LAB). Therefore, this study aimed to isolate and characterize LAB with different proteolytic activities from Iranian artisanal white cheeses. The isolates were classified into low, medium, and high proteolytic activity clusters via K-means clustering and identified as Lactiplantibacillus (Lpb.) pentosus L11, Lpb. plantarum L33, and Enterococcus faecium L13, respectively. Some safety tests (such as resistance to antibiotics, hemolytic activity, and biogenic amine production), probiotic properties (including cell surface hydrophobicity, auto/co-aggregation, and antibacterial activity), and production of volatile compounds were evaluated. These were non-hemolytic and non-biogenic amine producers, and showed no irregular antibiotic resistance. Lpb. plantarum L33 had the highest hydrophobicity (30.55%) and auto-aggregation (49.56%), and the highest co-aggregation was observed for Lpb. pentosus L11 with Staphylococcus aureus (61.51%). The isolates also showed a remarkable antibacterial effect against pathogenic bacteria. Moreover, Lpb. pentosus L11 and Lpb. plantarum L33 with low and medium proteolytic activity produced a wider range of volatile compounds in milk compared to the strain with a high proteolytic effect. The results showed that a probiotic strain with low or medium proteolytic activity could improve the flavor characteristics of fermented milk.

Technological and safety assessment of selected lactic acid bacteria for cheese starter cultures design: Enzymatic and antimicrobial activity, antibiotic resistance and biogenic amine production

Twenty lactic acid bacteria (LAB) isolated from artisanal cheeses and previously selected for their technological properties were screened for their enzymatic activities, antimicrobial activity and safety. The aim was to select those LAB strains that were safe and showed advantageous properties for the development of starter cultures for cheese making, discarding those that could transfer antibiotic resistance or produce any toxic biogenic amines. Aminopeptidase activities were detected in most strains, particularly high for the substrate leucine arylamidase, and most lactobacilli and Leuconostoc strains showed high β-galactosidase activity. Glutamate dehydrogenase (GDH) activity was detected in 13 strains, although the activity values varied widely. All strains showed antimicrobial activity against the indicator microorganisms due to acid production. However, only one of the Lactiplantibacillus plantarum strains showed an inhibitory activity against Enterococcus faecalis due to bacteriocin-like compounds. In particular, Levilactobacillus brevis TAUL1567 and Lactiplantibacillus paraplantarum TAUL1399 showed resistance to tetracycline and ampicillin, respectively, above the cut-off values and were therefore excluded. Tyramine was only produced by L. brevis TAUL1567 (193.15 μg ml−1), while putrescine was produced by this strain and two strains of Lactococcus lactis. Finally, 14 strains produced γ-aminobutyric acid (GABA), five of them at concentrations around or above 100 μg ml−1.

Metabiotics Signature through Genome Sequencing and In Vitro Inhibitory Assessment of a Novel Lactococcus lactis Strain UTNCys6-1 Isolated from Amazonian Camu-Camu Fruits

Metabiotics are the structural components of probiotic bacteria, functional metabolites, and/or signaling molecules with numerous beneficial properties. A novel Lactococcus lactis strain, UTNCys6-1, was isolated from wild Amazonian camu-camu fruits (Myrciaria dubia), and various functional metabolites with antibacterial capacity were found. The genome size is 2,226,248 base pairs, and it contains 2248 genes, 2191 protein-coding genes (CDSs), 50 tRNAs, 6 rRNAs, 1 16S rRNA, 1 23S rRNA, and 1 tmRNA. The average GC content is 34.88%. In total, 2148 proteins have been mapped to the EggNOG database. The specific annotation consisted of four incomplete prophage regions, one CRISPR-Cas array, six genomic islands (GIs), four insertion sequences (ISs), and four regions of interest (AOI regions) spanning three classes of bacteriocins (enterolysin_A, nisin_Z, and sactipeptides). Based on pangenome analysis, there were 6932 gene clusters, of which 751 (core genes) were commonly observed within the 11 lactococcal strains. Among them, 3883 were sample-specific genes (cloud genes) and 2298 were shell genes, indicating high genetic diversity. A sucrose transporter of the SemiSWEET family (PTS system: phosphoenolpyruvate-dependent transport system) was detected in the genome of UTNCys6-1 but not the other 11 lactococcal strains. In addition, the metabolic profile, antimicrobial susceptibility, and inhibitory activity of both protein-peptide extract (PPE) and exopolysaccharides (EPSs) against several foodborne pathogens were assessed in vitro. Furthermore, UTNCys6-1 was predicted to be a non-human pathogen that was unable to tolerate all tested antibiotics except gentamicin; metabolized several substrates; and lacks virulence factors (VFs), genes related to the production of biogenic amines, and acquired antibiotic resistance genes (ARGs). Overall, this study highlighted the potential of this strain for producing bioactive metabolites (PPE and EPSs) for agri-food and pharmaceutical industry use.

A Concerted Redox- and Light-Activated Agent for Controlled Multimodal Therapy against Hypoxic Cancer Cells.

Hypoxia represents a remarkably exploitable target for cancer therapy, is encountered only in solid human tumors, and is highly associated with cancer resistance and recurrence. Here, a hypoxia-activated mitochondria-accumulated Ru(II) polypyridyl prodrug functionalized with conjugated azo (Az) and nitrogen mustard (NM) functionalities, RuAzNM, is reported. This prodrug has multimodal theranostic properties toward hypoxic cancer cells. Reduction of the azo group in hypoxic cell microenvironments gives rise to the generation of two primary amine products, a free aniline mustard, and the polypyridyl RuNH2 complex. Thus, the aniline mustard triggers generation ofreactive oxygen species (ROS) and mtDNA crosslinking. Meanwhile, the resultant biologically benign phosphorescent RuNH2 gives rise to a diagnostic signal and signals activation of the phototherapy. This multimodal therapeutic effect eventually elevates ROS levels, depletes reduced nicotinamide adenine dinucleotide (NADH) and adenosine triphosphate (ATP), and induces mitochondrial membrane damage, mtDNA damage, and ultimately cell apoptosis. This unique strategy allows controlled multimodal theranostics to be realized in hypoxic cells and multicellular spheroids, making RuAzNM a highly selective and effective cancer-cell-selective theranostic agent (IC50 = 2.3µm for hypoxic HepG2 cancer cells vs 58.2µm for normoxic THL-3 normal cells). This is the first report of a metal-based compound developed as a multimodal theranostic agent for hypoxia.

Metagenomic Type IV Aminotransferases Active toward (R)-Methylbenzylamine

Aminotransferases (ATs) are pyridoxal 5′-phosphate-dependent enzymes that catalyze the reversible transfer of an amino group from an amino donor to a keto substrate. ATs are promising biocatalysts that are replacing traditional chemical routes for the production of chiral amines. In this study, an in silico-screening of a metagenomic library isolated from the Curonian Lagoon identified 11 full-length fold type IV aminotransferases that were successfully expressed and used for substrate profiling. Three of them (AT-872, AT-1132, and AT-4421) were active toward (R)-methylbenzylamine. Purified proteins showed activity with L- and D-amino acids and various aromatic compounds such as (R)-1-aminotetraline. AT-872 and AT-1132 exhibited thermostability and retained about 55% and 80% of their activities, respectively, even after 24 h of incubation at 50 °C. Active site modeling revealed that AT-872 and AT-4421 have an unusual active site environment similar to the AT of Haliscomenobacter hydrossis, while AT-1132 appeared to be structurally related to the AT from thermophilic archaea Geoglobus acetivorans. Thus, we have identified and characterized PLP fold type IV ATs that were active toward both amino acids and a variety of (R)-amines.

Breakdown and Productivity Prediction of Dragline using Machine Learning Algorithms

Dragline operations play a major role in the overall production of coal in open cast mining. Hence, it becomes necessary to maximize the working hours and minimize the idle and breakdown hours as it affects the overall production of a mine. There is also a shortage of skilled labour for dragline operations and combined with the time-to-time breakdown of dragline, it results in a production deficit. In this study, extensive research is carried out using machine learning algorithms on data obtained from one of the largest opencast mines in Singrauli. The data consists of the parameters that were maintained by the staff on a regular basis, and the algorithm tried to learn the underlying patterns between the independent and dependent variables and find the correlation between the parameters that have a significant impact on productivity and breakdown, which were the dependent variables. The results obtained from the algorithms are encouraging and, with certain improvements in data collection procedures, can improve the prediction accuracy to an effective level. An increase in the frequency of data collection and expanding the data recording using sensors to the electrical and mechanical parameters along with the specific type of failure in the dragline machine will further improve the accuracy of the model and can provide beforehand information so that the machine could be handed over to maintenance department for the change of faulty parts and necessary precautions that can be taken to prevent the breakdown which will result in an overall reduction of idle and breakdown hours and increase in overall production.

Enzyme Grafting with a Cofactor-Decorated Metal-Organic Capsule for Solar-to-Chemical Conversion.

Semi-artificial approaches to solar-to-chemical conversion can achieve chemical transformations that are beyond the capability of natural enzymes, but face marked challenges to facilitate in vivo cascades, due to their inevitable need for cofactor shuttling and regeneration. Here, we report on an enzyme grafting strategy to build a metal-organic capsule-docking artificial enzyme (metal-organic-enzyme, MOE) that comprised the self-assembly of a cofactor-decorated capsule and the supramolecular enzyme-recognition features between the enzyme scaffold and the capsule to bypass cofactor shuttling and regeneration. The incorporated NADH mimics within the metal-organic capsule interacted with the imine intermediate that formed from the condensation of the amines and the dehydrogenation of alcohol substrates in the microenvironment to form complexes within the capsule and subsequently served as an in situ-generated photoresponsive cofactor. Upon illumination, the photoresponsive cofactor facilitates efficient proton/electron transport between the inner space (supramolecular hydrogenation) and outer space (enzymatic dehydrogenation) of the capsule to dehydrogenize the alcohols and hydrogenize the imine intermediates, respectively, circumventing the conventionally complex multistep cofactor shuttling and regeneration. The semi-artificial enzyme endows the conversion of diverse types of alcohol to amine products in both aqueous/organic solutions and Escherichia coli with high efficiency, offering a wide range of opportunities for sustainable and environmentally friendly biomanufacturing of commodity and fine chemicals.

Mechanistic Investigation of Zirconium-Catalyzed Hydroaminoalkylation of Alkynes: Substrate and Ligand Effects

The mechanism of zirconium-catalyzed hydroaminoalkylation of diphenylacetylene, and the origin of the contrasting reactivity with N-benzylaniline or N-(trimethylsilyl)benzylamine substrates, have been investigated. Isolated intermediates have revealed that the nature of the C–H activation and C–C bond-forming steps in alkyne hydroaminoalkylation are analogous to those of the alkene variant, regardless of the amine substrate. In the zirconium-catalyzed hydroaminoalkylation of alkynes, the open coordination sphere at the zirconium center, supported by the bis(ureate) ligand, enables the coordination of neutral protic donors. This is essential for promoting catalytic turnover in these reactions. Under catalytic conditions, dimethylamine acts as a proton source for releasing the allylic amine products while minimizing the formation of side products. Additionally, we identified the formation of a homoleptic tetra(ureate) zirconium complex as the main catalyst decomposition pathway in catalytic alkyne hydroaminoalkylation. The formation of similar homoleptic structures is further favored when employing smaller bis(urea) proligands, thus explaining the poor performance of some ligands in catalysis. However, further increasing the bis(urea) proligand size to minimize such catalyst decomposition favors isomerization side-products resulting in reduced yields of the desired product. This study provides ligand design principles that guide the development of coordinatively flexible catalysts to achieve catalytic turnover in systems that rely upon protonolysis steps, as in hydroaminoalkylation.

Fermented Soybean Paste Attenuates Biogenic Amine-Induced Liver Damage in Obese Mice

Biogenic amines are cellular components produced by the decarboxylation of amino acids; however, excessive biogenic amine production causes adverse health problems. The relationship between hepatic damage and biogenic amine levels in nonalcoholic fatty liver disease (NAFLD) remains unclear. In this study, mice were fed a high-fat diet (HFD) for 10 weeks to induce obesity, presenting early-stage of NAFLD. We administered histamine (20 mg/kg) + tyramine (100 mg/kg) via oral gavage for 6 days to mice with HFD-induced early-stage NAFLD. The results showed that combined histamine and tyramine administration increased cleaved PARP-1 and IL-1β in the liver, as well as MAO-A, total MAO, CRP, and AST/ALT levels. In contrast, the survival rate decreased in HFD-induced NAFLD mice. Treatment with manufactured or traditional fermented soybean paste decreased biogenically elevated hepatic cleaved PARP-1 and IL-1β expression and blood plasma MAO-A, CRP, and AST/ALT levels in HFD-induced NAFLD mice. Additionally, the biogenic amine-induced reduction in survival rate was alleviated by fermented soybean paste in HFD-induced NAFLD mice. These results show that biogenic amine-induced liver damage can be exacerbated by obesity and may adversely affect life conservation. However, fermented soybean paste can reduce biogenic amine-induced liver damage in NAFLD mice. These results suggest a beneficial effect of fermented soybean paste on biogenic amine-induced liver damage and provide a new research perspective on the relationship between biogenic amines and obesity.

New insights into the role of key microorganisms and wooden barrels during lambic beer fermentation and maturation

Belgian lambic beers are still produced through traditional craftsmanship. They rely on a spontaneous fermentation and maturation process that is entirely carried out in wooden barrels. The latter are used repetitively and may introduce some batch-to-batch variability. The present systematic and multiphasic study dealt with two parallel lambic beer productions carried out in nearly identical wooden barrels making use of the same cooled wort. It encompassed a microbiological and metabolomic approach. Further, a taxonomic classification and metagenome-assembled genome (MAG) investigation was based on shotgun metagenomics. These investigations provided new insights into the role of these wooden barrels and key microorganisms for this process. Indeed, besides their role in traditionality, the wooden barrels likely helped in establishing the stable microbial ecosystem of lambic beer fermentation and maturation by acting as an inoculation source of the necessary microorganisms, thereby minimizing batch-to-batch variations. They further provided a microaerobic environment, which aided in achieving the desirable succession of the different microbial communities for a successful lambic beer production process. Moreover, these conditions prevented excessive growth of acetic acid bacteria and, therefore, uncontrolled production of acetic acid and acetoin, which may lead to flavor deviations in lambic beer. Concerning the role of less studied key microorganisms for lambic beer production, it was shown that the Acetobacter lambici MAG contained several acid tolerance mechanisms toward the harsh environment of maturing lambic beer, whereas genes related to sucrose and maltose/maltooligosaccharide consumption and the glyoxylate shunt were absent. Further, a Pediococcus damnosus MAG possessed a gene encoding ferulic acid decarboxylase, possibly contributing to 4-vinyl compound production, as well as several genes, likely plasmid-based, related to hop resistance and biogenic amine production. Finally, contigs related to Dekkera bruxellensis and Brettanomyces custersianus did not possess genes involved in glycerol production, emphasizing the need for alternative external electron acceptors for redox balancing.

C−N Coupling through Hydroaminoalkylation on a Single‐Atom Rh Heterogeneous Catalyst

AbstractC−N coupling is significant for the synthesis of fine chemicals toward various applications. Hydroaminoalkylation of olefins is a tandem reaction of C−N coupling involving first the formation of an aldehyde through hydroformylation of an olefin and then the production of amine through reductive amination of the aldehyde. Here we report a stable, supported catalyst of singly dispersed Rh1 atoms anchored on TiO2 (P25) nanoparticles designated as Rh1/P25. Its high activity for C−N coupling was demonstrated by six hydroaminoalkylations of olefins and amines with selectivity of higher than 90% for producing tertiary amines. The singly dispersed Rh1O4 on P25 exhibit activity and selectivity for hydroaminoalkylation comparable or even higher than some reported molecular catalysts. In contrast to molecular catalysts, the Rh‐based single‐atom Rh heterogeneous catalysis (Rh1/P25) can be readily separated from reactants and products, reused for multiple runs of hydroaminoalkylation, and recycled with a low cost.

C-N Coupling through Hydroaminoalkylation on a Single-Atom Rh Heterogeneous Catalyst.

C-N coupling is significant for the synthesis of fine chemicals toward various applications. Hydroaminoalkylation of olefins is a tandem reaction of C-N coupling involving first the formation of an aldehyde through hydroformylation of an olefin and then the production of amine through reductive amination of the aldehyde. Here we report a stable, supported catalyst of singly dispersed Rh1 atoms anchored on TiO2 (P25) nanoparticles designated as Rh1 /P25. Its high activity for C-N coupling was demonstrated by six hydroaminoalkylations of olefins and amines with selectivity of higher than 90% for producing tertiary amines. The singly dispersed Rh1 O4 on P25 exhibit activity and selectivity for hydroaminoalkylation comparable or even higher than some reported molecular catalysts. In contrast to molecular catalysts, the Rh-based single-atom Rh heterogeneous catalysis (Rh1 /P25) can be readily separated from reactants and products, reused for multiple runs of hydroaminoalkylation, and recycled with a low cost.

The effect of seasonality on the biogenic amines, free amino acids, and physico-chemical composition of raw milk Fiore Sardo cheese produced in Sardinia (Italy)

The effect of seasonality on the content of biogenic amines (BA), compounds that could threaten food safety at a high level, were evaluated in Fiore Sardo, a typical artisanal raw sheep's milk cheese produced in Sardinia. The cheese samples collected from six farms, after four months of ripening, were manufactured from January to June. The relationship between the BA content, the free amino acid (FAA) concentration, and the physico-chemical composition (pH, a w , NaCl, humidity, and the fat and protein content) was considered. The FAA and BA contents were determined by HPLC-FL. The BA content and the other parameters analysed were significantly affected (p ≤ 0.000) by seasonality and the farm of origin. Despite the differences attributable to the producers, the seasonal variations of all the parameters considered followed the same trend. As the season changed, the level of total BA grew, reaching a mean content of 1402 ± 207 mg/kg in the samples produced in June, almost five times the mean value of those manufactured in January. The most represented biogenic amine was tyramine, followed by putrescine and cadaverine. Histamine was determined almost exclusively in some samples produced in the warmer months, while β-phenylethylamine and tryptamine were found in a low concentration or not detected. The winter products did not exceed the threshold of 900 mg/kg proposed for the total BA in food, while most of the samples manufactured in the hottest months exceeded this limit, posing a potential risk to consumers' health. The total FAA and BA content were correlated (p = 0.01), indicating that with the change of the season, proteolysis phenomena increased and made the precursor amino acids available for microbial decarboxylase activity. In addition, from January to June, the pH and fat levels grew, while those of a w , humidity and NaCl tended to decline. The study highlighted that as the season changed, the rise in temperature, probably combined with the increment of fat and decrement of NaCl content, could favour proteolysis phenomena and bacterial decarboxylase activity and, as a result, the escalation of BA production. Interventions in the production protocol to reduce the negative effect of seasonality on cheese safety are needed. In addition, in light of these results, it is possible to speculate that the rising temperature and the predicted lengthening of the warm season due to climate change, which also seems to affect the spring periods, could create the ideal conditions for the production of biogenic amines for an increasingly extended phase of the year.

Genetic and Probiotic Characteristics of Urolithin A Producing Enterococcus faecium FUA027.

Enterococcus faecium FUA027 transforms ellagic acid (EA) to urolithin A (UA), which makes it a potential application in the preparation of UA by industrial fermentation. Here, the genetic and probiotic characteristics of E. faecium FUA027 were evaluated through whole-genome sequence analysis and phenotypic assays. The chromosome size of this strain was 2,718,096 bp, with a GC content of 38.27%. The whole-genome analysis revealed that the genome contained 18 antibiotic resistance genes and seven putative virulence factor genes. E. faecium FUA027 does not contain plasmids and mobile genetic elements (MGEs), and so the transmissibility of antibiotic resistance genes or putative virulence factors should not occur. Phenotypic testing further indicated that E. faecium FUA027 is sensitive to clinically relevant antibiotics. In addition, this bacterium exhibited no hemolytic activity, no biogenic amine production, and could significantly inhibit the growth of the quality control strain. In vitro viability was >60% in all simulated gastrointestinal environments, with good antioxidant activity. The study results suggest that E. faecium FUA027 has the potential to be used in industrial fermentation for the production of urolithin A.

HAT‐Promoted Electrochemical Amination: C(sp2)−H/N−H Cross Dehydrogenative Coupling

AbstractA direct amination of quinoxalin‐2(1H)‐ones via electrochemical C(sp2)−H/N−H cross dehydrogenative coupling was established by using TMSN3as the hydrogen atom transfer (HAT) reagent. Remarkable features of this synthetic strategy include operational simplicity, transition metal‐ and chemical oxidant‐free conditions, and broad functional group tolerance. A wide range of primary, secondary amines and quinoxalinones are tolerated, giving the corresponding secondary and tertiary amination products in good to excellent yields.magnified image