Thiazolidinones: novel insights from microwave synthesis, computational studies, and potentially bioactive hybrids

• Luan A. Martinho,
• Victor H. J. G. Praciano,
• Guilherme D. R. Matos,
• Claudia C. Gatto and
• Carlos Kleber Z. Andrade

Beilstein J. Org. Chem. 2025, 21, 2618–2636, doi:10.3762/bjoc.21.203

• explored. One notable approach is the use of microwave irradiation. Microwave-assisted synthesis has proven effective in reducing reaction times and improving yields [59][60][61][62]. Herein, we report the synthesis of 5-arylidene derivatives from rhodanine or thiazolidine-2,4-dione via the Knoevenagel

• % of EDDA at 80 °C for 30 minutes under microwave irradiation. Despite this later methodology looks very efficient, the method reported here enables the in situ generation of the catalyst, allowing for an expanded reaction scope with 2,4-TZD derivatives (23 examples) and also proving effective for

Pentacyclic aromatic heterocycles from Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles

• Kaylen D. Lathrum,
• Emily M. Hanneken,
• Katelyn R. Grzelak and
• James T. Fletcher

Beilstein J. Org. Chem. 2025, 21, 2524–2534, doi:10.3762/bjoc.21.194

• phenanthridines, naphthyridines, and phenanthrolines were prepared via Pd-catalyzed annulation of 1,5-diaryl-1,2,3-triazoles. Analogs with triazole N1-connected ortho-bromobenzene subunits successfully underwent annulation under microwave irradiation in yields of 31–90%. In contrast, annulations of triazole C1

• -connected ortho-bromobenzene subunit analogs failed under microwave irradiation but were successful using conventional thermal heating in yields of 31–65%. The expanded nature of the aromatic ring system following annulation was reflected by the downfield shifting of aromatic 1H NMR signals and the red

• tandem approach preparing 7–12 ranged from 43–85%, which were similar to running the deprotection and cycloaddition reactions sequentially. Pd-catalyzed annulation using a modification of previously reported reaction conditions [46] under microwave irradiation instead of thermal heating converted 1,5

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

Switchable pathways of multicomponent heterocyclizations of 5-amino-1,2,4-triazoles with salicylaldehydes and pyruvic acid

• Yana I. Sakhno,
• Oleksander V. Buravov,
• Kostyantyn Yu. Yurkov,
• Anastasia Yu. Andryushchenko,
• Svitlana V. Shishkina and
• Valentyn A. Chebanov

Beilstein J. Org. Chem. 2025, 21, 2030–2035, doi:10.3762/bjoc.21.158

• devoted to the study of the reactions of aminoazoles, pyruvic acid and its derivatives with salicylaldehydes and it was found that depending on the conditions (reaction time, temperature, and method of process activation, in particular ultrasound and microwave irradiation), different types of heterocycles

Continuous-flow-enabled intensification in nitration processes: a review of technological developments and practical applications over the past decade

• Feng Zhou,
• Chuansong Duanmu,
• Yanxing Li,
• Jin Li,
• Haiqing Xu,
• Pan Wang and
• Kai Zhu

Beilstein J. Org. Chem. 2025, 21, 1678–1699, doi:10.3762/bjoc.21.132

• technologies including ultrasonication, microwave irradiation, and microreaction technology into conventional nitration frameworks. Nikseresht et al. developed a novel heterogeneous heteropoly acid catalyst (PMA@MIL-53(Fe)), enabled efficient regioselective nitration of phenols under ultrasonic irradiation

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

• harness their Lewis-acidic and weakly oxidizing properties, respectively. In addition, microwave irradiation increases the reaction rate considerably. Furthermore, the use of a solid Cu(I) catalyst immobilized on an aminated silica support allows for a heterogeneous and cost-effective process, featuring

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

• microwave irradiation to enhance the protocol’s efficacy. The non-thermal effects and unique ability of MW irradiation to promote reactions catalysed by solid-supported metals have already been demonstrated [53]. As shown in Scheme 1, our research is in line with earlier studies that highlight the

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

• initial GBB reaction of aminopyridines 1 (0.5 mmol), isocyanides 3 (1.2 equiv), and furfuraldehydes 2 (1.2 equiv) was conducted in 3:1 CH2Cl2/MeOH (4 mL) using Yb(OTf)3 (0.08 equiv) as a Lewis acid catalyst under microwave irradiation at 100 °C for 1 h (Scheme 2). Nineteen distinct adducts 4 were obtained

• GBB reactions for the preparation of imidazo[1,2-a]pyridines 4 were conducted using aminopyridines 1 (0.5 mmol), isocyanides 3 (0.6 mmol, 1.2 equiv), and furfuraldehyde 2 (0.6 mmol, 1.2 equiv) in 3:1 DCM/MeOH (4 mL) with Yb(OTf)3 (0.04 mmol, 0.08 equiv) as a Lewis acid catalyst under microwave

• irradiation at 100 °C for 1 h (Scheme 2, Table S1 in Supporting Information File 1). Nineteen distinct adducts 4 were obtained in 89–98% yields. The reactions of GBB adducts 4 with acryloyl chloride (5, 1.5 equiv) in the presence of Et3N (2 equiv) at room temperature in anhydrous CH2Cl2 for 6 h afforded 19 N

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

• recourse to treatments such as pyrolysis, ultrasonic carbonization, hydrothermal, solvothermal, or microwave irradiation [13][14][15][16][17]. The properties of CDs can be tuned by doping them with various elements, which influence photophysical and electrochemical properties, stability, and

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

• technologies [37][38], and microwave irradiation [39][40][41][42] have been developed. The electrochemical synthetic method is a creative, simple, and new process for preparing organophosphorus compounds [43]. In recent years, various articles have been reported on the electrochemical synthesis of

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

• (63–86%) [16]. As many of these protocols employ toxic, highly reactive and moisture-sensitive reagents, our work will exploit microwave technology and the environmentally benign nature of amino acids to construct the hydantoin scaffold. Microwave irradiation technology has proven significant

• advantages over conventional heating, such as enhanced reaction rates and yields [17]. Microwave irradiation is also aligned with our group’s sustainability goals of adhering to the principles of green chemistry [18]. Following our previous works in the synthesis and evaluation of biologically active

• were first verified using different equivalents of KOCN at different temperatures in water under microwave heating conditions (Scheme 1, Table 1), and 5.0 equiv of KOCN and microwave irradiation at 80 °C produced the best yield for H1a (Table 1, entry 2). Inspired by the simplicity of the procedure, a

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

• notably. Later, the same group developed an alternative method by using glyoxylic acid immobilized on silica, and the reaction conditions were optimized using microwave irradiation and avoiding the use of solvent or additional catalysts [93]. In this way, derivatives of 42a were obtained in good yields

Cu(OTf)₂-catalyzed multicomponent reactions

• Sara Colombo,
• Camilla Loro,
• Egle M. Beccalli,
• Gianluigi Broggini and
• Marta Papis

Beilstein J. Org. Chem. 2025, 21, 122–145, doi:10.3762/bjoc.21.7

• -workers in 2003 (Scheme 13) [28]. Working in acetonitrile at room temperature, very high yields were obtained with recycling of the catalyst with negligible loss of activity. The reaction is successful also by operating it in ethanol as a solvent under microwave irradiation [29]. More recently, the

• reaction is facilitated under microwave irradiation and can be extended to the preparation of an imidazo-fused (benzo)thiazole skeleton 34 starting from (benzo)thiazol-2-ones instead of pyridin-2-ones. Moreover, the Cu(OTf)2 in [bmim]BF4 can be recovered and reused for multiple processes. The key step of

Direct trifluoroethylation of carbonyl sulfoxonium ylides using hypervalent iodine compounds

• Radell Echemendía,
• Carlee A. Montgomery,
• Fabio Cuzzucoli,
• Antonio C. B. Burtoloso and
• Graham K. Murphy

Beilstein J. Org. Chem. 2024, 20, 3182–3190, doi:10.3762/bjoc.20.263

• M) with Cs2CO3 (1.0 equiv) under microwave irradiation at 70 °C for 10 min. Though the yield only improved by 5% compared with using 1.3 equiv of 2a, these were nonetheless adopted as the optimal reaction conditions. Once the optimal reaction conditions were established, we then investigated the

Multicomponent reactions driving the discovery and optimization of agents targeting central nervous system pathologies

• Lucía Campos-Prieto,
• Aitor García-Rey,
• Eddy Sotelo and
• Ana Mallo-Abreu

Beilstein J. Org. Chem. 2024, 20, 3151–3173, doi:10.3762/bjoc.20.261

• obtained intermediates with the appropriate commercial lactams, under microwave irradiation (Scheme 8). As a result, compound 8a has been identified as a promising derivative potentially useful in further AD drug discovery for its antioxidant activity (4.7 TE in ORAC-FL assay), moderate hAChE inhibition

• , isocyanide, and TMSN3, after which the Ugi adduct is treated with an excess of different isocyanates resulting in the corresponding hydantoin derivatives. Finally, under microwave irradiation, the Boc group is removed under acid conditions and the benzodiazepine core is formed after ring closure (Scheme 18

Evaluating the halogen bonding strength of a iodoloisoxazolium(III) salt

• Dominik L. Reinhard,
• Anna Schmidt,
• Marc Sons,
• Julian Wolf,
• Elric Engelage and
• Stefan M. Huber

Beilstein J. Org. Chem. 2024, 20, 2401–2407, doi:10.3762/bjoc.20.204

• ), 0.1 M, 135 h at rt, 43%, (b) 1.5 equiv mCPBA, 3.0 equiv TfOH (at 0 °C), (DCM), 0.1 M, 20 h at rt, 85%, (c) 1.0 equiv NaBArF24, (acetone), 0.5 M, 2 h at 50 °C under microwave irradiation, 72%. Gold(I)-catalyzed cyclization of propargylic amide 11 as benchmark reaction for Au–Cl activation. Determined

Asymmetric organocatalytic synthesis of chiral homoallylic amines

• Nikolay S. Kondratyev and
• Andrei V. Malkov

Beilstein J. Org. Chem. 2024, 20, 2349–2377, doi:10.3762/bjoc.20.201

• crystal XRD of the corresponding hydrochloride salt. Microwave-induced one-pot asymmetric allylation of in situ-formed arylimines, catalysed by (R)-3,3’-diphenyl-BINOL. Aldehyde and amine scope [26]. aThe reaction was conventionally heated at 50 °C for 24 hours instead of microwave irradiation. b1.0 equiv

• -Cope rearrangement of in situ-formed aldimines using allyl transfer reagent 116 [42]. (S)-TRIP-catalysed enantioconvergent aza-Cope rearrangement of β-formyl amides, substrate scope [43]. aThe yield was measured after hydrolysis of the benzophenone imine. bThe reaction required 300 W microwave

• irradiation at 130 °C for 6 hours. cIsolated dr. (S)-TRIP-catalysed enantioconvergent aza-Cope rearrangement of β-formyl amides 16–19, amide and allyl group scope [43]. aThe yield was measured after the benzophenone imine hydrolysis. bThe isolated dr. Synthetic applications of homoallylic N-benzophenone imine

Deuterated reagents in multicomponent reactions to afford deuterium-labeled products

• Kevin Schofield,
• Shayna Maddern,
• Yueteng Zhang,
• Grace E. Mastin,
• Rachel Knight,
• Wei Wang,
• James Galligan and
• Christopher Hulme

Beilstein J. Org. Chem. 2024, 20, 2270–2279, doi:10.3762/bjoc.20.195

• deuteration of formamide product while increasing formamide equivalents increases the yield at the cost of deuterated %. Excess reaction time increases side product formation and thermal degradation of the aldehyde starting material. To combat this, microwave irradiation was employed which dramatically

From perfluoroalkyl aryl sulfoxides to ortho thioethers

• Yang Li,
• Guillaume Dagousset,
• Emmanuel Magnier and
• Bruce Pégot

Beilstein J. Org. Chem. 2024, 20, 2108–2113, doi:10.3762/bjoc.20.181

• conditions, a significant amount of degradation products was observed and the yield was rather low. The same result was obtained when the reagent was first added at 0 °C and then heated for one hour under microwave irradiation (Table 1, entry 2). To avoid degradation, the temperature was reduced while the

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

• tested in a previous study [3]. The reaction requires rather severe heating under microwave irradiation (200 °C, chlorobenzene, sealed vial), ensuring complete conversion of the diazo compound in a rather short time. Initial experiments using p-anisidine as a nucleophile showed that the target β-lactam

Syntheses and medicinal chemistry of spiro heterocyclic steroids

• Laura L. Romero-Hernández,
• Ana Isabel Ahuja-Casarín,
• Penélope Merino-Montiel,
• Sara Montiel-Smith,
• José Luis Vega-Báez and
• Jesús Sandoval-Ramírez

Beilstein J. Org. Chem. 2024, 20, 1713–1745, doi:10.3762/bjoc.20.152

• out, resulting in the corresponding N-tosylhydrazones 51a–c. Afterwards, the compounds were subjected to microwave irradiation in the presence of (3-azidopropyl)boronic acid and potassium or cesium carbonate, yielding 3-spiropyrrolidines 52a–c in high overall yields as 1:1 mixture of diastereomers

Synthetic applications of the Cannizzaro reaction

• Bhaskar Chatterjee,
• Dhananjoy Mondal and
• Smritilekha Bera

Beilstein J. Org. Chem. 2024, 20, 1376–1395, doi:10.3762/bjoc.20.120

• KSF clays as recyclable and heterogeneous catalysts to catalyze the Cannizzaro reaction by 1,4-diazabicyclo[2.2.2]octane under microwave irradiation and solvent-free conditions giving the products in excellent yields within seconds. The solid clay applied in the first cycle can be recovered and reused

• in subsequent reactions. Reddy and coworkers carried out the Cannizzaro reaction of aromatic aldehydes to the corresponding alcohols in high yields by crossed-Cannizzaro reactions employing solid-supported KF-Al2O3 as catalyst [26] under microwave irradiation using solvent-free conditions. The use of

• ). Huang et al. set up a clean crossed-Cannizzaro-aldol reaction strategy of isatin derivatives 88 and 90 with paraformaldehyde under microwave irradiation to furnish 3,3-disubstituted oxindole derivatives 89a–h and 91a–d [92]. The representative 3-hydroxymethyloxindole adducts with varying substituents

Innovative synthesis of drug-like molecules using tetrazole as core building blocks

• Jingyao Li,
• Ajay L. Chandgude,
• Qiang Zheng and
• Alexander Dömling

Beilstein J. Org. Chem. 2024, 20, 950–958, doi:10.3762/bjoc.20.85

• reaction conditions with or without solvents at low or high temperature under microwave irradiation and the results are summarized in Table 1. Notably, the reaction with water as a solvent provided a promising yield of 52%, whereas other solvents and conditions resulted only in trace product formation

Green and sustainable approaches for the Friedel–Crafts reaction between aldehydes and indoles

• Periklis X. Kolagkis,
• Eirini M. Galathri and
• Christoforos G. Kokotos

Beilstein J. Org. Chem. 2024, 20, 379–426, doi:10.3762/bjoc.20.36

• development of greener synthetic technologies, like photocatalysis, organocatalysis, the use of nanocatalysts, microwave irradiation, ball milling, continuous flow, and many more. Thus, in this review, we summarize the medicinal properties of BIMs and the developed BIM synthetic protocols, utilizing the

• inspired by the use of ʟ-proline-modified magnetic nanoparticles reported by Khalafi-Nezhad et al., synthesized nano-Fe3O4@ʟ-cysteine for the green synthesis of BIMs, employing microwave irradiation to avoid long reaction times [117]. A mixture of the reagents and 100 mg of nano-Fe3O4@ʟ-cysteine per 1

• equiv of the carbonyl compound, was exposed to 350 W of microwave irradiation, at an internal temperature of 80 °C, at solvent-free conditions, for 3 to 7 minutes, providing optimum yields for aromatic aldehydes and ketones. Isolated product yields approached 83–93%, even after 10 reaction cycles with

N-Sulfenylsuccinimide/phthalimide: an alternative sulfenylating reagent in organic transformations

• Fatemeh Doraghi,
• Seyedeh Pegah Aledavoud,
• Mehdi Ghanbarlou,
• Bagher Larijani and
• Mohammad Mahdavi

Beilstein J. Org. Chem. 2023, 19, 1471–1502, doi:10.3762/bjoc.19.106

• -thiophthalimides led to sulfenamides promoted by 2-ethoxyethanol under microwave irradiation [100]. Alkylamines, such as morpholine, cyclohexylamine, pyrrolidine, and tert-butylamine were participated in this coupling process. All reactions occurred in a shorter time with higher chemical yields compared to the