A dicationic nickel complex-catalyzed asymmetric synthesis of chiral benzylic amines: Evolution from reductive amination to borrowing hydrogen reaction

Brønsted acid–metal synergy in Ni/HZSM-5 for reductive amination of biomass-derived furfural to furfurylamine

Efficient photocatalytic conversion of biomass-derived hydroxyl acids to amino acids over Ni/CdS.

Dual-site synergistic catalysis on carbon defects and Lewis acids for reductive amination of lignin derivatives to cyclohexylamine

Herein, an engineered amine dehydrogenase is developed as an exemplary closed-boundary catalytic system for addressing the substrate scope-enantioselectivity dilemma. Asymmetric reductive amination with essentially quantitative enantioselectivity is demonstrated, with a K68S, N261L, A113G, T134G mutant of Bacillus species REN16 Glu/Leu/Phe/Val amino acid dehydrogenase for structurally diverse ketones. Reciprocal conformational adaptation, with complementary matching of conformational flexibility and sterics on both the enzyme and substrate sides, is proposed as the working mechanism.

Reduced peptide bonds of the methyleneamino Ψ[CH2-NH] type are widely recognized as peptide bond isosteres with significant value in drug discovery and development. Solid-Phase Synthesis (SPS) enables Solid-Phase Fragment Condensation (SPFC), a key strategy for the construction of complex peptides. In this study, we report the SPS of peptides containing selectively side-chain deprotected homoserine (Hse) residues, followed by solution-phase oxidation of the liberated Hse side-chain hydroxyl group to the corresponding γ-aldehydes. The intrinsic instability of these intermediates, primarily due to intramolecular cyclization to γ-hydroxy lactam or lactone products, is systematically examined, and stabilization strategies to overcome these limitations are developed. The resulting stabilized homoserinyl γ-aldehyde peptides were subsequently employed, as proof of concept, in solid-phase reductive amination with the N-terminus of resin-bound peptides. Overall, this approach enables the efficient formation of Hse-β-Ψ[CH2-NH] reduced peptide bonds and establishes a versatile platform for broader peptide ligation and modification strategies.

Borane-amine complexes occupy an increasingly important position in modern main-group chemistry. Their tunable electronic and steric properties offer a balance between the high reactivity of borane and enhanced stability provided by amine coordination, making them unique reagents for organic synthesis and materials chemistry. This feature article presents a review of the recent advances in the synthesis of borane-amines, as well as their diverse synthetic applications. The main synthetic strategies for the preparation of borane-amines, direct reaction with diborane or in situ generated borane, salt metathesis, and Lewis base exchange, are discussed in detail with emphasis on recent protocols and borane-ammonia preparation techniques. Applications of borane-amines in organic synthesis where they serve as selective and more easily handled alternatives to traditional borane reagents include reduction, reductive amination, and hydroboration reactions. Recent progress demonstrates that beyond their use as practical borane alternatives, borane-amines offer distinct mechanistic and synthetic utility in transfer hydrogenation, borylation, B-H insertion, as sources of amine-ligated boryl radicals, and as amine surrogates in amidation methodologies. This feature article aims to consolidate recent developments in well-known reactions and emerging methodologies, as well as underscore the growing role of borane-amines as adaptable tools in synthetic organic chemistry.

Generation of enantiospecific monoclonal antibodies against (2R,6R)-hydroxynorketamine.

Developing sustainable routes to biodegradable polymers from renewable feedstocks is key to reducing reliance on petroleum and mitigating environmental pollution. Amino acids, such as L‐alanine, are valuable monomers for biodegradable nylons. Artificial photosynthesis has recently been applied to amino acid synthesis, yet the use of biomass‐derived nitrogen sources such as urea in visible‐light driven L‐alanine synthesis has not yet been explored. Here, we present a novel artificial photosynthetic system that converts urea and pyruvate, both biomass‐derived compounds, into L‐alanine under visible light. In this system, a visible light‐driven NADH regeneration system consisting of triethanolamine (TEOA), zinc meso‐tetra(4‐sulfonatophenyl)porphyrin tetrasodium salt (ZnTPPS4−), and pentamethylcyclopentadienyl (Cp*) rhodium 2,2′‐bipyridine (bpy) ([Cp*Rh(bpy)(H2O)]2+) is integrated with urease (URE), hydrolyzes urea into ammonia, and L‐alanine dehydrogenase (AlDH), catalyzes the reductive amination of pyruvate. Under irradiation, the system produced 0.85 mM L‐alanine after 24 h (85% yield based on pyruvate). This work represents the first exploration of urea‐based, visible‐light powered enzymatic L‐alanine synthesis, offering a sustainable route to biodegradable polymer precursors from renewable nitrogen and carbon sources.

Biomass derived magnetically separable heterogeneous iron nanocatalyst for reduction of nitroarenes and reductive amination of carbonyl compounds under sustainable conditions

The catalytic reductive amination of biomass-derived carbonyl compounds into value-added primary amines has attracted significant attention in renewable biomass upgrading. Herein, highly dispersed Ru clusters embedded nitrogen-doped hollow carbon spheres...

Ru-based catalyst with controlled loading on CeMOF nanoislands for reductive amination of furfural to furfurylamine

Electron acceptor NiO regulates the reduction of Cu supported on TiO2 for the efficient vapor-phase reductive amination of 1, 6-hexanediol

Engineering and immobilization of imine reductase enable chemoenzymatic synthesis of SLC6A19 inhibitor JNT-517.

Construction of N-benzylanilines via facile metal-free tandem reductive amination of benzaldehydes with nitrobenzenes

Reactive interfacial oxygen vacancies in Ru/TiO2 for efficient reductive amination of bio-based carbonyl compounds

Traditional biocatalytic cascades typically require discrete enzymes for each synthetic step. Here, we report unprecedented trifunctional imine reductases (IRED) that conduct three sequential transformations-alkene reduction, intramolecular reductive amination, and imine reduction-all within a single catalytic cycle. This elegant single-enzyme catalytic system directly transforms linear substrates into enantiomerically pure 2-aryl pyrrolidines via a concerted cascade without intermediate isolation. Combining density functional theory (DFT) calculations and mechanistic studies, we elucidate how the IRED achieves step-selective catalysis. Our findings establish a proof-of-concept for simplifying complex biocatalytic cascades using multifunctional enzymes, offering a powerful strategy to streamline synthetic pathways.

Dedication: Dedicated with admiration and gratitude to Professor Giuseppe Resnati on his 70th birthday, for his pioneering and enduring contributions to fluorine chemistry and the art of noncovalent bonding. The 1,3-proton shift reaction has emerged as a highly convenient, scalable, and synthetically practical strategy for accessing fluorinated amines and amino acids - structural motifs that play a pivotal role in the design of contemporary pharmaceuticals and agrochemicals. This transformation typically proceeds via a biomimetic reductive amination of fluorinated carbonyl compounds, wherein a benzylamine derivative functions dually as the nitrogen source and as a formal reducing agent. Over the past decade, substantial progress has been achieved in this domain, particularly through the strategic use of 1,3-azaallylic anion intermediates in reactions with a broad array of electrophiles. A notable advancement involves the adoption of 2,2-diphenylglycine as a synthetically advantageous alternative to the conventionally employed diphenylmethylamine. In this review, we underscore the benefits of this modification and examine its application across reactions with diverse electrophilic partners, including aldehydes, imines, and allyl alcohol-derived species, enabling the synthesis of vicinal amino alcohols, vicinal diamines, homoallylamines, and α-methylene-γ-amino acids

Fatty amines (FAMs), aliphatic amines possessing a mostly linear C8+ hydrocarbon fragments, are large-capacity chemicals widely used in production of detergents, emulsifiers, adjuvants, fabric softeners, fuel and oil additives, corrosion inhibitors, etc. The current technologies of FAMs are based on fatty acids (nitrile process) and alcohols, obtained from triglycerides and petrochemical feedstocks. Alternative catalytic approaches to amines, intensively studied in recent decades, are direct amination of alkenes, reductive amination and aminomethylation of carbonyl compounds, hydrogen-borrowing amination of alcohols, and single-stage triglyceride or waste conversion. However, only a fraction of recent top-rated works was related to the synthesis of FAMs. In the present review, we describe and discuss above-mentioned current and prospective catalytic approaches to FAMs. The advantages and shortcomings of these approaches are evaluated from the practical point of view, indicating the most promising directions of the further industrially oriented research.

This study reports the development of a novel signal amplification carrier based on the soluble macromolecular polysaccharide Ficoll400 to enhance the sensitivity of chemiluminescent immunoassays (CLIA), with a particular focus on detecting low-abundance biomarkers, such as high-sensitivity cardiac troponin I (hs-cTnI). The carrier was constructed via the reductive amination of Ficoll400, followed by conjugation with streptavidin (SA), thereby generating dense SA binding sites capable of attaching numerous biotinylated horseradish peroxidase (Bio-HRP) molecules to amplify the chemiluminescent signal. Comparative analyses with other polysaccharides (Dextran T500 and hyaluronic acid) demonstrated that Ficoll400 conjugates, especially when aminated with l-lysine, provided superior signal enhancement with minimal background noise, improving the signal-to-noise ratio by up to 140-fold. Characterization by SDS-PAGE, dynamic light scattering, and transmission electron microscopy confirmed the formation of large macromolecular structures conducive to signal amplification. Optimization of experimental parameters, such as conjugation ratios, pH, buffer composition, and surfactant presence, further enhanced the assay performance. The developed hs-cTnI CLIA method exhibited excellent analytical sensitivity, with a limit of detection of 0.5 pg·mL-1 and a limit of quantitation of 0.9 pg·mL-1, alongside robust stability under accelerated and onboard conditions and high precision, with coefficients of variation below 10%. Clinical sample testing demonstrated strong correlation and consistency with a commercial hs-cTnI assay, confirming the method's reliability and potential for clinical application. Overall, the Ficoll400-SA amplification carrier provides a stable, biocompatible, and easily prepared platform that significantly enhances immunoassay sensitivity, with promising applications for the detection of various low-abundance biomarkers in vitro.