Recent advances in copper-catalyzed direct hydroamination of alkenes with (hetero)aromatic amines

• Hyejeong Lee and
• Yunmi Lee

Beilstein J. Org. Chem. 2026, 22, 925–947, doi:10.3762/bjoc.22.73

• )-catalyzed tandem oxidative amidation/aza-Michael reaction for the efficient synthesis of 3-substituted N-pyridinylisoindolinones 28 from 2-aminopyridines 25 and alkyl (E)-3-(2-formylphenyl)acrylates 26 (Scheme 9b) [47]. Under open-flask conditions at 80 °C in DMF, the reaction proceeded efficiently in the

• presence of CuI (3 mol %), affording the corresponding isoindolinone products 28 in good to excellent yields (79–92%). Mechanistically, the transformation involves a Cu(I)-promoted oxidative amidation followed by intramolecular aza-Michael cyclization. Initially, the condensation of amine with the aldehyde

• isoindolinone framework 28. Mechanistic studies further revealed that electron-rich aminopyridines favor oxidative amidation, followed by intramolecular conjugate addition, whereas electron-deficient substrates might divert the reaction toward alternative cyclization processes. Zhong et al. reported a copper

A practical CO₂-mediated synthesis of 5,6-carboxylated silicon-rhodamines for targeted probe development

• Dongjie Hou,
• Shaowei Wu,
• Ning Xu,
• Pengjun Bao,
• Wenhao Jia,
• Qinglong Qiao and
• Zhaochao Xu

Beilstein J. Org. Chem. 2026, 22, 915–924, doi:10.3762/bjoc.22.72

• derivatives can be directly used in subsequent amidation reactions with targeting ligands without column chromatography, facilitating the rapid construction of high-performance targeted fluorescent probes. Overall, this strategy provides a straightforward, efficient, and practical synthetic route for the

Chiral cyclopropenimine-catalyzed enantioselective Michael reactions of phenol and benzofuran-derived α,β-unsaturated pyrazolamides with benzophenone-imine of glycine esters

• Ya Bai,
• Xue-Ying Wang,
• Si-Kai Zhu,
• Yan-Ting Shen,
• Sheng-Yong Zhang and
• Ping-An Wang

Beilstein J. Org. Chem. 2026, 22, 888–896, doi:10.3762/bjoc.22.69

• Michael adducts in high yields and enantioselectivities in the presence of Lambert catalyst CSB-1. Therefore, the phenol-derived pyrazolamides 5a–l were prepared from phenols, ethyl 4-bromocrotonate and 3,5-dimethyl-1H-pyrazole in three steps including alkylation, hydrolysis and amidation (Scheme 2a). The

Recent advances in the cleavage of non-activated amides

• Eun-Sol Choi and
• Hyo-Jun Lee

Beilstein J. Org. Chem. 2026, 22, 352–369, doi:10.3762/bjoc.22.23

• . Bioactive molecule-derived amides with complex structures smoothly underwent acyl iodide generation, thereby furnishing the products 132, 133, and 134 in 85%, 82%, and 88% yield, respectively, via in-situ amidation with aniline. The scope of amine nucleophiles was broad as well. Anilines, primary amines

• intermediate 121. The amide product is then formed by acyl substitution of the acyl iodide with the amine nucleophile. Since the amidation proceeds through acyl iodide intermediates, a wide range of carboxylic acid derivatives can be generated simply by varying the nucleophile. For example, replacing the amine

• intermediate. The in-situ amidation of the resulting acyl fluoride with ʟ-valine methyl ester produced 210 in 61% yield with 93:7 dr and 99% ee. In 2024, a metal-free photoredox catalytic method for the transamidation of PMB anilides was developed [77]. This protocol emphasizes chemoselective cleavage and

Synthesis of new tetra- and pentacyclic, methylenedioxy- and ethylenedioxy-substituted derivatives of the dibenzo[c,f][1,2]thiazepine ring system

• Gábor Berecz,
• András Dancsó,
• Mária Tóthné Lauritz,
• Loránd Kiss,
• Gyula Simig and
• Balázs Volk

Beilstein J. Org. Chem. 2025, 21, 2645–2656, doi:10.3762/bjoc.21.205

• amidation (48), N-methylation (49), and hydrolysis (50), as well as the direct amidation of 47 to 49 worked well, the Friedel–Crafts cyclization via the corresponding acyl chloride to the tetracyclic key intermediate 51 could only be carried out with 26% yield, obviously because of incomplete

C2 to C6 biobased carbonyl platforms for fine chemistry

• Jingjing Jiang,
• Muhammad Noman Haider Tariq,
• Florence Popowycz,
• Yanlong Gu and
• Yves Queneau

Beilstein J. Org. Chem. 2025, 21, 2103–2172, doi:10.3762/bjoc.21.165

Discovery of cytotoxic indolo[1,2-c]quinazoline derivatives through scaffold-based design

• Daniil V. Khabarov,
• Valeria A. Litvinova,
• Lyubov G. Dezhenkova,
• Dmitry N. Kaluzhny,
• Alexander S. Tikhomirov and
• Andrey E. Shchekotikhin

Beilstein J. Org. Chem. 2025, 21, 2062–2071, doi:10.3762/bjoc.21.161

• methodologies from traditional acylation/carbamoylation [9] to advanced Pd- or Rh-catalyzed C–H activation [10][11], FeIII–CuII/p-TSA–CuI catalyzed ring expansion/cyclization [12], electrochemical C–H/N–H functionalization [13], RhIII-catalyzed C–H amidation [14], etc. In contrast to chemical studies, a

Photoswitches beyond azobenzene: a beginner’s guide

• Michela Marcon,
• Christoph Haag and
• Burkhard König

Beilstein J. Org. Chem. 2025, 21, 1808–1853, doi:10.3762/bjoc.21.143

Research progress on calixarene/pillararene-based controlled drug release systems

• Liu-Huan Yi,
• Jian Qin,
• Si-Ran Lu,
• Liu-Pan Yang,
• Li-Li Wang and
• Huan Yao

Beilstein J. Org. Chem. 2025, 21, 1757–1785, doi:10.3762/bjoc.21.139

• Biotin-SAC4A by modifying SAC4A with biotin. (Figure 16) [124]. Monocarboxylated azocalixarene and aminated biotin were synthesized. Subsequently, using a coupling agent, the carboxyl group of the azocalixarene was modified through amidation to obtain biotin-modified SAC4A. The formation of amide bonds

Photocatalysis and photochemistry in organic synthesis

• Timothy Noël and
• Bartholomäus Pieber

Beilstein J. Org. Chem. 2025, 21, 1645–1647, doi:10.3762/bjoc.21.128

• of alkenylboronic esters using energy transfer catalysis [26]. Gualandi and co-workers leveraged a combination of photoredox and HAT catalysis to realize the intramolecular nucleophilic amidation of alkenes with β-lactams [27]. Further, Luridiana and colleagues developed a method for the alkylation

A multicomponent reaction-initiated synthesis of imidazopyridine-fused isoquinolinones

• Ashutosh Nath,
• John Mark Awad and
• Wei Zhang

Beilstein J. Org. Chem. 2025, 21, 1161–1169, doi:10.3762/bjoc.21.92

• as HIV inhibitors [14]. The imidazo[1,2-a]pyridine ring can be readily synthesized by the GBB reaction [10][15], while the isoquinolinone ring is commonly generated by a cyclative lactamization process. Performing a GBB reaction followed by an intramolecular amidation is a good approach for making

• imidazopyridine-fused isoquinolinones. The Veljkovic group employed methyl 2-formylbenzoate for the GBB reaction to form adducts I which undergoes intramolecular amidation to afford product A (Scheme 1A) [16]. In a patent filed by Tibotec Pharmaceuticals, substituted alkyl isonitriles were used for the GBB

Investigations of amination reactions on an antimalarial 1,2,4-triazolo[4,3-a]pyrazine scaffold

• Henry S. T. Smith,
• Ben Giuliani,
• Kanchana Wijesekera,
• Kah Yean Lum,
• Sandra Duffy,
• Aaron Lock,
• Jonathan M. White,
• Vicky M. Avery and
• Rohan A. Davis

Beilstein J. Org. Chem. 2025, 21, 1126–1134, doi:10.3762/bjoc.21.90

• -position of the pyrazine ring [10][11]. During small-scale late-stage functionalisation of natural products, we have observed that amination or amidation with primary amines often involves less of a kinetic barrier than might otherwise be expected [12][13][14]. The use of readily available liquid amines in

Recent advances in synthetic approaches for bioactive cinnamic acid derivatives

• Betty A. Kustiana,
• Galuh Widiyarti and
• Teni Ernawati

Beilstein J. Org. Chem. 2025, 21, 1031–1086, doi:10.3762/bjoc.21.85

• -dithiocyanatopyrimidine (NDTP) as the coupling reagent for cinnamic acid amidation with swift reaction time (Scheme 4) [22]. The reaction of cinnamic acid (7) with NDTP resulted in the active acyl thioester 11 followed by a reaction with an amine to give the corresponding amide 10. The byproduct of the coupling reagent

• could be recycled by adding POCl3 and KSCN, thus promoting the reagent’s sustainability by reducing waste. Carboxyl group activation can also be achieved by using triazine-based reagents. For example, Saberi and Salimiyan (2019) applied 2,4,6-trichloro-1,3,5-triazine (TCT) to perform amidation of

• applications in organic reactions. Similarly, Kunishima and co-workers (2021) utilized (N,N’-dialkyl)triazinedione-4-(dimethylamino)pyridine (ATD-DMAP) for the amidation of cinnamic acid (7) to generate the corresponding amide 10 in excellent yield (Scheme 5B) [37]. Mechanistically, the carboxyl group attacks

Regioselective formal hydrocyanation of allenes: synthesis of β,γ-unsaturated nitriles with α-all-carbon quaternary centers

• Seeun Lim,
• Teresa Kim and
• Yunmi Lee

Beilstein J. Org. Chem. 2025, 21, 800–806, doi:10.3762/bjoc.21.63

• 98% yield. Ortho-bromoaryl-substituted nitrile 3m also underwent tandem amidation and copper-catalyzed cyclization, efficiently producing lactam 9 in a 98% yield. Scheme 7 illustrates a plausible reaction mechanism based on previous studies [34]. The process begins with the formation of NHC–copper

Entry to 2-aminoprolines via electrochemical decarboxylative amidation of N‑acetylamino malonic acid monoesters

• Olesja Koleda,
• Janis Sadauskis,
• Darja Antonenko,
• Edvards Janis Treijs,
• Raivis Davis Steberis and
• Edgars Suna

Beilstein J. Org. Chem. 2025, 21, 630–638, doi:10.3762/bjoc.21.50

• 10.3762/bjoc.21.50 Abstract The electrochemical synthesis of 2-aminoprolines based on anodic decarboxylation–intramolecular amidation of readily available N-acetylamino malonic acid monoesters is reported. The decarboxylative amidation under Hofer–Moest reaction conditions proceeds in an undivided cell

• [7][8] (Figure 2, reactions 1 and 2, respectively). Results and Discussion N-Acetylamino malonic acid monoester 9a possessing a tosyl-protected tethered amine was selected as a model substrate for the development of the intramolecular amidation under Hofer–Moest conditions. The acid 9a was prepared

• in three steps (62% overall yield) from commercially available diethyl acetamidomalonate by an alkylation/hydrolysis/Boc-cleavage sequence (Scheme 1). The development of decarboxylative amidation commenced by examining the published conditions for anodic decarboxylation/etherification [4

Cryptophycin unit B analogues

• Thomas Schachtsiek,
• Jona Voss,
• Maren Hamsen,
• Beate Neumann,
• Hans-Georg Stammler and
• Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 526–532, doi:10.3762/bjoc.21.40

• coupled to either one of the two unit A precursors 18 and 19 by Yamaguchi esterification. CDA fragments 20 and 21 were connected to unit B derivatives 11 and 13 through amidation which provided seco-cryptophycins 22 and 23 in yields of 49% and 38%, respectively. Starting from seco-cryptophycin 22

Dioxazolones as electrophilic amide sources in copper-catalyzed and -mediated transformations

• Seungmin Lee,
• Minsuk Kim,
• Hyewon Han and
• Jongwoo Son

Beilstein J. Org. Chem. 2025, 21, 200–216, doi:10.3762/bjoc.21.12

• widely used as N-acylamide sources in amidation processes of challenging substrates, typically employing precious transition metals. However, these catalytic systems often present several challenges associated with cost, toxicity, stability, and recyclability. Among the 3d transition metals, copper

• advancements in the synthetic transformations of dioxazolones, with particular examples of copper salts. Keywords: amidation; copper salts; dioxazolones; electrophilic nitrogen; N-acyl nitrene; Introduction Dioxazolones, first synthesized and reported by Beck and co-workers [1], have been employed as

• electrophiles in various nucleophilic transformations due to their susceptibility to rapid decomposition into the corresponding isocyanates (Scheme 1a) [2][3]. They have attracted increasing interest as electrophilic amide sources in amidation using transition-metal catalysts such as ruthenium, rhodium, and

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• /CH2Cl2 at room temperature (17% yield). Subjecting the methoxylated benzaldehyde intermediate 9 to a Doebner–Knoevenagel condensation with malonic acid and pyridine afforded the brominated cinnamic acid analogue 10 in 54% yield [19]. Amidation chemistry using carbonyldiimidazole (CDI) [18] and the

Photoredox-catalyzed intramolecular nucleophilic amidation of alkenes with β-lactams

• Valentina Giraldi,
• Giandomenico Magagnano,
• Daria Giacomini,
• Pier Giorgio Cozzi and
• Andrea Gualandi

Beilstein J. Org. Chem. 2024, 20, 2461–2468, doi:10.3762/bjoc.20.210

Multicomponent syntheses of pyrazoles via (3 + 2)-cyclocondensation and (3 + 2)-cycloaddition key steps

• Ignaz Betcke,
• Alissa C. Götzinger,
• Maryna M. Kornet and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2024, 20, 2024–2077, doi:10.3762/bjoc.20.178

Negishi-coupling-enabled synthesis of α-heteroaryl-α-amino acid building blocks for DNA-encoded chemical library applications

• Matteo Gasparetto,
• Balázs Fődi and
• Gellért Sipos

Beilstein J. Org. Chem. 2024, 20, 1922–1932, doi:10.3762/bjoc.20.168

• heteroaromatic halides. The reaction sequence utilizes a photochemically enhanced Negishi cross-coupling as a key step, followed by oximation and reduction. The prepared amino esters were validated for on-DNA reactivity via a reverse amidation–hydrolysis–reverse amidation protocol. Keywords: amino acids; DEL

• first attached to carboxylic acid functionalized DNA headpiece 7a (first reverse amidation). Next, the ester was hydrolyzed to obtain acid 9, and finally, a second reverse amidation with aniline afforded 10. Both the reverse amidation and the ester hydrolysis were performed following literature

Access to 2-oxoazetidine-3-carboxylic acid derivatives via thermal microwave-assisted Wolff rearrangement of 3-diazotetramic acids in the presence of nucleophiles

• Ivan Lyutin,
• Vasilisa Krivovicheva,
• Grigory Kantin and
• Dmitry Dar’in

Beilstein J. Org. Chem. 2024, 20, 1894–1899, doi:10.3762/bjoc.20.164

• high yields of the target compounds. When stored individually or in solution at room temperature, the acids 4 gradually decompose and undergo decarboxylation and other accompanying processes. The example of acid 4a demonstrates the possibility of easy amidation to form new β-lactam derivatives 3s and

• acids and their subsequent amidation has been demonstrated. Synthetic routes to 2-oxoazetidine-3-carboxylic acid derivatives. Scope of diazotetramic acids 1 thermolysis in the presence of various nucleophiles. PMP = p-methoxyphenyl, PCP = p-chlorophenyl, PMB = p-methoxybenzyl, PFB = p-fluorobenzyl

• ; reaction scale – 0.25 mmol; ascaled-up (1.5 mmol) yield. Negative results with several N-, O-, and C-nucleophiles and with diazo reagent 1m. Preparation of acids 4 by hydrogenolysis of benzyl esters and examples of acid 4a amidation. Supporting Information Deposition Number CCDC 2323689 (for 3t) contains

Sustainable tandem acylation/Diels–Alder reaction toward versatile tricyclic epoxyisoindole-7-carboxylic acids in renewable green solvents

• Ayhan Yıldırım

Beilstein J. Org. Chem. 2024, 20, 1308–1319, doi:10.3762/bjoc.20.114

• ][98]. Therefore, in the present study, we report for the first time a milder, greener strategy to prepare a series of epoxyisoindolinones from aminofuranes and maleic anhydride via cascade amidation and stereocontrolled IMDAF reaction in bio-based solvents as an alternative reaction medium. Results

• ] cycloaddition between maleic anhydride and secondary amine occurs first, followed by the corresponding amidation (Figure 3, path II) [110]. Although IMDAF reactions involving furan systems bearing amide functionality are generally reversible [134], the formation of the addition products in high yields in this

Oxidative hydrolysis of aliphatic bromoalkenes: scope study and reactivity insights

• Amol P. Jadhav and
• Claude Y. Legault

Beilstein J. Org. Chem. 2024, 20, 1286–1291, doi:10.3762/bjoc.20.111

• the regioisomeric mixture of Ritter-type amidation side products 3. Conclusion In summary we have developed a hypervalent iodine-catalyzed synthetic method for the oxidative hydrolysis of diverse dialkyl bromoalkenes. The current approach can tolerate both symmetrical as well as unsymmetrical dialkyl

Three-component N-alkenylation of azoles with alkynes and iodine(III) electrophile: synthesis of multisubstituted N-vinylazoles

• Jun Kikuchi,
• Roi Nakajima and
• Naohiko Yoshikai

Beilstein J. Org. Chem. 2024, 20, 891–897, doi:10.3762/bjoc.20.79

• ], and sulfonic acids [31]. On the other hand, nitrogen-based nucleophiles amenable to this reaction manifold have thus far been limited to nitriles in the context of Ritter-type iodo(III)amidation [29]. In light of the significance of vinylated azoles, our attention was attracted to the feasibility of