Copper catalysis: a constantly evolving field

• Elena Fernández and
• Jaesook Yun

Beilstein J. Org. Chem. 2025, 21, 1477–1479, doi:10.3762/bjoc.21.109

• yield of up to 99%, with excellent regio- and E-selectivities. The method could be used for functional-group transformations of amines, amides, and lactams, as well as for gram-scale syntheses, demonstrating synthetic usefulness and versatility. A complementary Full Research Paper by Martina and co

Microwave-enhanced additive-free C–H amination of benzoxazoles catalysed by supported copper

• Andrei Paraschiv,
• Valentina Maruzzo,
• Filippo Pettazzi,
• Stefano Magliocco,
• Paolo Inaudi,
• Daria Brambilla,
• Gloria Berlier,
• Giancarlo Cravotto and
• Katia Martina

Beilstein J. Org. Chem. 2025, 21, 1462–1476, doi:10.3762/bjoc.21.108

• environmental abundance, low cost and low overall toxicity. A wide range of aminating reagents have been utilised, including nitrogen electrophiles and amines in the presence of external or internal oxidants [27], in many types of copper-catalysed synthetic protocols. The direct copper-catalysed C–H amination

• of azolic substrates, but here the amines and the ligands are still used in excess and auxiliary oxidants are occasionally employed [33][34][35]. Although electrophilic amines, such as chloroamines [36][37], hydroxylamine [38][39][40], acylated hydroxylamine (with a wider reaction scope) [41][42][43

• , that still required high temperatures, but the excess of amine (2 equiv) was lowered and only a catalytic amount of acid was utilised. Similar acidic protocols were subsequently developed by Li et al. [46], in which benzoxazoles were reacted with secondary amines and amides, with higher temperature

Advances in nitrogen-containing helicenes: synthesis, chiroptical properties, and optoelectronic applications

• Meng Qiu,
• Jing Du,
• Nai-Te Yao,
• Xin-Yue Wang and
• Han-Yuan Gong

Beilstein J. Org. Chem. 2025, 21, 1422–1453, doi:10.3762/bjoc.21.106

• corresponding lactams 29d and 29e and amines 29f and 29g were also obtained. Compounds 29a and 29b exhibit λabs centered at 513 nm, while the amines 29f and 29g display high ФF values of 0.48 and 0.56, respectively. Notably, azocine derivative 29b exhibits the highest CPL activity among the series, with a |glum

High-pressure activation for the solvent- and catalyst-free syntheses of heterocycles, pharmaceuticals and esters

• Kelsey Plasse,
• Valerie Wright,
• Guoshu Xie,
• R. Bernadett Vlocskó,
• Alexander Lazarev and
• Béla Török

Beilstein J. Org. Chem. 2025, 21, 1374–1387, doi:10.3762/bjoc.21.102

• that achieving these reactions at even higher scales is reasonable. The reactions occurred in a similar fashion as they did at the mg scale [36] and all reactions produced higher than 96% isolated yield of the product. Where the two alkyl amines were used, the reactions were complete within 30 s of

• alcohols with acetic acid. Molecular volumes of the reactants and products and the reaction volume (ΔV) for the Paal–Knorr reaction of amines with 2,5-hexanedione. Supporting Information Supporting Information File 6: Materials and methods, spectral data of new compounds, and HRMS spectra of known

Oxetanes: formation, reactivity and total syntheses of natural products

• Peter Gabko,
• Martin Kalník and
• Maroš Bella

Beilstein J. Org. Chem. 2025, 21, 1324–1373, doi:10.3762/bjoc.21.101

• challenging amines. The combination of simple reaction conditions and excellent chemoselectivity makes this protocol very robust and suitable for both the academia and industry. Kinetic and computational experiments support an SN1 mechanism via loss of sulphur dioxide and oxetane carbocation formation. Two

• benzotriazole-adduct formation proceeds poorly with sterically demanding secondary amines and fails with primary amines. However, the latter may be overcome by adding a temporary benzyl group on the amine which can be subsequently cleaved by hydrogenolysis as demonstrated by the authors. Finally, it was shown

• access to a large library of functionalised oxetanes in moderate to excellent yields and under very simple reaction conditions, which are compatible with a wide range of nucleophiles including alcohols (primary, secondary and tertiary), phenols, aliphatic and aromatic amines or heteroaryls (e.g., furan

Recent advances in oxidative radical difunctionalization of N-arylacrylamides enabled by carbon radical reagents

• Jiangfei Chen,
• Yi-Lin Qu,
• Ming Yuan,
• Xiang-Mei Wu,
• Heng-Pei Jiang,
• Ying Fu and
• Shengrong Guo

Beilstein J. Org. Chem. 2025, 21, 1207–1271, doi:10.3762/bjoc.21.98

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

• vitro and in vivo antimalarial drug leads. With a view to generating a library of unique antimalarial 1,2,4-triazolo[4,3-a]pyrazines and exploring regiochemical preference for nucleophilic amines, we utilised the known synthetic 5-chloro-3-(4-chlorophenyl)-[1,2,4]triazolo[4,3-a]pyrazine (1) as a

• scaffold for aminations with 14 commercially available primary amines. Reacting scaffold 1 with excess primary amine at room temperature for 16 h generated the desired amine analogues in respectable yields (18–87%) and high purity (≥95%) following chromatography workup. The structures of the 14 previously

• -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

• cinnamic acid. For example, Chen and co-workers (2020) reported the Pd-catalyzed N-acylation of cinnamic acids using tertiary amines to generate the corresponding amides 83 and 84 in good yields via C–N cleavage (Scheme 25) [61]. The active Pd0 species was inserted into the carboxylate group to afford the

• cyclopropenone 333 followed by the second cyclopropenone ring-opening (335) (Scheme 75B) [128]. Leyva-Pérez and co-workers (2022) reported the esterification and amidation of diphenylcyclopropenone (309) with alcohols and amines, respectively, catalyzed by Cu(II) (Scheme 76A) [129]. In addition, they prepared a

• , Suryavanshi and co-workers (2020) utilized PhI(OAc)2 to mediate the oxidative olefination of amines and Wittig reagents 415 to give the corresponding cinnamate esters 416–419 via formation of imines 421 (Scheme 87B) [148]. In addition, a gram scale operation has been conducted smoothly. 3.1.3 Carbene

Biobased carbon dots as photoreductants – an investigation by using triarylsulfonium salts

• Valentina Benazzi,
• Arianna Bini,
• Ilaria Bertuol,
• Mariangela Novello,
• Federica Baldi,
• Matteo Hoch,
• Alvise Perosa and
• Stefano Protti

Beilstein J. Org. Chem. 2025, 21, 1024–1030, doi:10.3762/bjoc.21.84

• ); triarylsulfonium salts; visible light; Introduction Carbon dots (CDs) are a class of zero-dimensional carbon-based semiconducting nanoparticles bearing on the surface a wide range of functional groups, such as carboxylic acids, alcohols, and amines, that garnered significant attention in the last decade among the

• + species, a process where transition-metal-based complexes are employed [29], often (in the case of Ru(II)-based derivatives) in the presence of tertiary amines as sacrificial reductants [27][28]. Nonetheless, while this work serves primarily as a preliminary study comparing the reducing power of various

Pd-Catalyzed asymmetric allylic amination with isatin using a P,olefin-type chiral ligand with C–N bond axial chirality

• Natsume Akimoto,
• Kaho Takaya,
• Yoshio Kasashima,
• Kohei Watanabe,
• Yasushi Yoshida and
• Takashi Mino

Beilstein J. Org. Chem. 2025, 21, 1018–1023, doi:10.3762/bjoc.21.83

• palladium catalysts with amines as nucleophiles have been reported [14][15][16][17][18][19][20][21][22][23][24][25], there have been only a few reports on the N-substitution of isatin using asymmetric methods. Recently, Wolf’s group reported a transition-metal-catalyzed (Pd-catalyzed) asymmetric allylic

Silver(I) triflate-catalyzed post-Ugi synthesis of pyrazolodiazepines

• Muhammad Hasan,
• Anatoly A. Peshkov,
• Syed Anis Ali Shah,
• Andrey Belyaev,
• Chang-Keun Lim,
• Shunyi Wang and
• Vsevolod A. Peshkov

Beilstein J. Org. Chem. 2025, 21, 915–925, doi:10.3762/bjoc.21.74

• ) triflate-catalyzed post-Ugi assembly of novel pyrazolo[1,5-a][1,4]diazepine scaffolds is reported offering high yields (up to 98%) under mild conditions. The synthetic sequence involves the Ugi four-component reaction (U4CR) of pyrazole-3-carbaldehydes, primary amines, 3-substituted propiolic acids, and

• employed the U4CR of ortho-halogenated benzaldehydes 7, primary amines 2, 3-substituted propiolic acids 8, and isocyanides 4 to synthesize propargylamides 9. These propargylic Ugi adducts 9 were subsequently subjected to a Cu-catalyzed tandem azide–alkyne cycloaddition/Ullmann coupling resulting in the

• account chemical and pharmacological importance of fused pyrazole derivatives [48][49][50][51][52][53], we herein report the post-Ugi assembly of novel pyrazolo[1,5-a][1,4]diazepine scaffolds 16 (Scheme 1d). The synthetic sequence involves an Ugi reaction of pyrazole-3-carbaldehydes 14, primary amines 2

Recent advances in controllable/divergent synthesis

• Jilei Cao,
• Leiyang Bai and
• Xuefeng Jiang

Beilstein J. Org. Chem. 2025, 21, 890–914, doi:10.3762/bjoc.21.73

• bromides) and the Lewis acid activator, a selective mono- or di-methylene insertion reaction can be carried out, generating α-/β-boryl-substituted tertiary organic amines 83 from simple secondary organic amines. Using N-alkyl-N-arylaminoboranes as the reactant, the reaction proceeds at −78 °C with CH2Br2

Cu–Bpin-mediated dimerization of 4,4-dichloro-2-butenoic acid derivatives enables the synthesis of densely functionalized cyclopropanes

• Patricia Gómez-Roibás,
• Andrea Chaves-Pouso and
• Martín Fañanás-Mastral

Beilstein J. Org. Chem. 2025, 21, 877–883, doi:10.3762/bjoc.21.71

• aliphatic gem-dichloride, we explored the feasibility of a base-mediated formation of chlorocyclopropanes (Table 2). Evaluation of bases such as metal tert-butoxides, phosphates, acetates, and organic amines resulted in either low conversion or decomposition of 2 (see Supporting Information File 1 for

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

• conditions and shows broad applicability to di- and trisubstituted allenes. Its practicality is demonstrated through the gram-scale synthesis and functional group transformations of amines, amides, and lactams, emphasizing its versatility and synthetic significance. Keywords: α-quaternary nitrile; Cu

• are important intermediates in organic syntheses because of the versatility of the cyano group, which can be readily transformed into a wide range of functional groups, including amides, carboxylic acids, amines, aldehydes, ketones, and N-heterocycles [6][7][8]. However, the synthesis of all-carbon

• synthesis and the successful transformation of nitrile products into amines, amides, and lactams. Further studies are underway to broaden the scope and application of the proposed method. Synthesis of acyclic nitrile-substituted quaternary carbon centers from allenes. Hydrocyanation of allene 1a with tosyl

Recent advances in the electrochemical synthesis of organophosphorus compounds

• Babak Kaboudin,
• Milad Behroozi,
• Sepideh Sadighi and
• Fatemeh Asgharzadeh

Beilstein J. Org. Chem. 2025, 21, 770–797, doi:10.3762/bjoc.21.61

• on the aromatic ring did not react in this system due to the incompatibility of the intermediate radicals. Electrochemical N–P bond formation Due to the importance of phosphoramidates in medicine and organic synthesis, Zhong et al. [64] reported an electrochemical P–N coupling of amines with dialkyl

New advances in asymmetric organocatalysis II

• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 766–769, doi:10.3762/bjoc.21.60

• ]. Kowalczyk and co-workers showed how asymmetric organocatalysis can benefit from mechanochemical activation. They established that Michael additions of thiomalonates to enones, catalyzed by cinchona-derived primary amines, is efficient and enantioselective under ball-milling conditions [24]. Kondratyev and

• Malkov reviewed the recent progress in the organocatalytic synthesis of chiral homoallylic amines. This important structural motif is typically made by asymmetric allylation of imines, and the authors describe various catalytic approaches as well as applications of these strategies in total synthesis [25

Origami with small molecules: exploiting the C–F bond as a conformational tool

• Patrick Ryan,
• Ramsha Iftikhar and
• Luke Hunter

Beilstein J. Org. Chem. 2025, 21, 680–716, doi:10.3762/bjoc.21.54

• scaffolds – alkanes – then we will progress to ethers, alcohols, sugars, amines (and their derivatives), carbonyl compounds, peptides, and finally sulfur-containing compounds. By arranging the material in this way, we hope that newcomers to the field might be able to readily envisage ways to apply these

• in the case of 84 which benefited from σC1–H → σ*C–F hyperconjugation [146][147]. 5 Amines We now turn to a very important and diverse class of molecules: the amines. Nitrogen-containing compounds are highly represented in many fields, including the pharmaceutical and agrochemical industries. It

• transpires that incorporating fluorine atoms nearby to nitrogen can affect the molecular properties of amines in several useful ways, notably including their conformations. In this section we will commence by examining fluorine-derived conformational control in simple linear amines, then we will move on to

Recent advances in allylation of chiral secondary alkylcopper species

• Minjae Kim,
• Gwanggyun Kim,
• Doyoon Kim,
• Jun Hee Lee and
• Seung Hwan Cho

Beilstein J. Org. Chem. 2025, 21, 639–658, doi:10.3762/bjoc.21.51

• showed a broad scope, tolerating both 1,1-diborylalkanes with N-tosyl-protected amines and TBS-protected alcohols, as well as substrates containing alkenes and alkynes. Various allylic bromides 46 with electron-rich and electron-deficient aryl substituents worked well, giving homoallylic boronic esters

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

• tetrahydropyran-containing amino acid derivatives via anodic decarboxylation of N-acetylamino malonic acid monoesters to generate a stabilized carbocation (Hofer–Moest conditions), which were then reacted with a tethered oxygen nucleophile [4]. In this follow-up study, we demonstrate that N-protected amines are

Sequential two-step, one-pot microwave-assisted Urech synthesis of 5-monosubstituted hydantoins from L-amino acids in water

• Wei-Jin Chang,
• Sook Yee Liew,
• Thomas Kurz and
• Siow-Ping Tan

Beilstein J. Org. Chem. 2025, 21, 596–600, doi:10.3762/bjoc.21.46

• methylated amino acids and carbamates (65–75%) [9] or cyanobenziodoxolone (CBX) (54–88%) [10]. Reactions using 1,2-diaza-1,3-dienes, amines, and isocyanates (47–76%) [11], as well as α-amino amides with triphosgene or carbonyldiimidazole (CDI) (41–80%) [12], have also been explored. Other strategies include

Formaldehyde surrogates in multicomponent reactions

• Cecilia I. Attorresi,
• Javier A. Ramírez and
• Bernhard Westermann

Beilstein J. Org. Chem. 2025, 21, 564–595, doi:10.3762/bjoc.21.45

• reactions [10]. Oxidation of the alcohol is done in situ to avoid problems regarding the isolation and instability of the aldehyde produced, although undesirable reactions, such as oxidation of the amines or isocyanides or overoxidation of the alcohol, could also be problematic [11][12]. In this regard

• , in a recent work, Pan et al. could chemoselectively oxidize methanol using a TEMPO-catalyzed electro-oxidation process, even in the presence of oxidizable amines, such as benzylamine, paving the way for the use of methanol as a formaldehyde surrogate in these isocyanide-based MCRs (Scheme 3) and

• . Quinazolinones 10 can be synthesized from substituted acetophenones and aromatic amines (Scheme 11) [44]. On the other hand, diarylpyridines 8, 9, and 11 can be obtained from acetophenones, but using aliphatic amines or ammonium formate as the nitrogen source [42][43]. In all these cases, the activation of DMSO

Study of the interaction of 2H-furo[3,2-b]pyran-2-ones with nitrogen-containing nucleophiles

• Constantine V. Milyutin,
• Andrey N. Komogortsev and
• Boris V. Lichitsky

Beilstein J. Org. Chem. 2025, 21, 556–563, doi:10.3762/bjoc.21.44

• with diverse N-nucleophiles was investigated. It was shown that the direction of the process depends on the type of employed nitrogen-containing reagent. For example, condensation with aliphatic amines leads to 2H-furo[3,2-b]pyran-2,7(3H)-diones bearing an exocyclic enamine moiety. At the same time

• structure of used N-nucleophile various types of a heterocyclic system can be obtained. A large number of examples of reactions with substituted amines have been reported in the literature. Generally, this process includes opening of the furanone ring followed by cyclization to the pyrrolone moiety [6][7][8

• ][9]. Wherein, the wide variety of easily available starting butenolides and amines allows one to create a huge array of practically useful products. At the same time, the application of hydrazine derivatives expands the range of formed heterocycles. So, along with the aforementioned N-substituted

Asymmetric synthesis of β-amino cyanoesters with contiguous tetrasubstituted carbon centers by halogen-bonding catalysis with chiral halonium salt

• Yasushi Yoshida,
• Maho Aono,
• Takashi Mino and
• Masami Sakamoto

Beilstein J. Org. Chem. 2025, 21, 547–555, doi:10.3762/bjoc.21.43

• , Chiba 263-8522, Japan 10.3762/bjoc.21.43 Abstract β-Amino cyanoesters are important scaffolds because they can be transformed into useful chiral amines, amino acids, and amino alcohols. Halogen bonding, which can be formed between halogen atoms and electron-rich chemical species, is attractive because

• excellent enantioselectivities (Figure 1c). Despite these successful examples, the construction of only one stereocenter has been reported to date. The Mannich reaction has great importance because of its utility in the preparation of useful chiral molecules such as amines [36], amino acids [37], and amino

• enantio- and diastereoselective Mannich reaction of α-cyanoesters with aldimines catalyzed by chiral amines, which provided β-amino cyanoesters in excellent yield and diastereoselectivities with up to 98% ee (Figure 2a) [41]. The Mannich reaction has been also applied in the construction of contiguous

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

• Alloc-protected cryptophycin 26 and both free amines 1 and 2 were tested against the human cervix carcinoma cell line KB-3-1 and its MDR subclone KB-V1 (Table 1) [33][34]. The m-chloro-p-(methylamino) derivative 1 showed high cytotoxicity with IC50 (KB-3-1) = 313 pM, which is perfectly between the

• amines still show nanomolar activity against the MDR cell line KB-V1 (Table 1) with resistance factors FR (being the ratio between IC50 (KB-V1) and IC50 (KB-3-1)) of 25 (1) and 34 (2), thus being comparably much more potent against KB-V1 cells than for example the unit D analogues (FR ≈ 103) [19

Organocatalytic kinetic resolution of 1,5-dicarbonyl compounds through a retro-Michael reaction

• James Guevara-Pulido,
• Fernando González-Pérez,
• José M. Andrés and
• Rafael Pedrosa

Beilstein J. Org. Chem. 2025, 21, 473–482, doi:10.3762/bjoc.21.34

• processes with low catalyst loading. It involves the kinetic resolution of alcohols, amines, and esters using chiral phosphoric acids [6][7][8][9][10][11][12][13] and sulfoximines with enals using chiral N-heterocyclic carbene (NHC) catalysts [14]. Additionally, these processes have been conducted using