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

Solar thermal fuels: azobenzene as a cyclic photon–heat transduction platform

• Jie Yan,
• Shaodong Sun,
• Minghao Wang and
• Si Wu

Beilstein J. Org. Chem. 2025, 21, 2036–2047, doi:10.3762/bjoc.21.159

• charged solar thermal fuels for deicing tests [74], showing effective ice removal capability under green light irradiation (Figure 7a). Wang et al. developed a photostimulated self-heating wristband [94] that elevates surface temperature from 29 °C to 44 °C upon blue light irradiation, protecting users

• irradiation (550 nm). Figure 7a was reprinted with permission from [74] Copyright © 2020 American Chemical Society. This content is not subject to CC BY 4.0. (b) Real-time infrared thermal imaging images of a charged self-heating wristband under blue light irradiation (450 nm). Figure 7b was reprinted from

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

• -triazoles, pyruvic acid, and salicylaldehydes were studied under different conditions. Upon conventional heating, benzotriazolooxadiazocine-5-carboxylic acids were formed in the three-component reactions as single reaction products. Upon ultrasonic activation or mechanical stirring at room temperature, the

• -triazoles, salicylaldehydes, and pyruvic acid were studied under different reaction conditions. In particular, it was found that the three-component reaction of an equimolar mixture of 5-amino-3-methylthio(methoxy)-1,2,4-triazole 1a,b, salicylaldehydes 2a–f, and pyruvic acid (3) under conventional heating

• behavior in this MCR. In the case of 3-carbomethoxy- and 3-(trifluoromethyl)-5-amino-1,2,4-triazoles the treatment with pyruvic acid and salicylaldehydes under thermal heating in different solvents (AcOH, DMF, n-butanol), instead of oxygen-bridged compounds gave a mixture of unidentified products with

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

Convenient alternative synthesis of the Malassezia-derived virulence factor malassezione and related compounds

• Karu Ramesh and
• Stephen L. Bearne

Beilstein J. Org. Chem. 2025, 21, 1730–1736, doi:10.3762/bjoc.21.135

• ) ketone, which could be converted to the corresponding bis(4-hydroxybenzyl) ketone (25c) by heating at 200 °C for 15 min to 3 h in the presence of pyridinium chloride [22][24]. Herein, we also show that the EDC-mediated coupling of 4-(benzyloxy)phenylacetic acid readily yields 25b, which may be

3-Aryl-2H-azirines as annulation reagents in the Ni(II)-catalyzed synthesis of 1H-benzo[4,5]thieno[3,2-b]pyrroles

• Julia I. Pavlenko,
• Pavel A. Sakharov,
• Anastasiya V. Agafonova,
• Derenik A. Isadzhanyan,
• Alexander F. Khlebnikov and
• Mikhail S. Novikov

Beilstein J. Org. Chem. 2025, 21, 1595–1602, doi:10.3762/bjoc.21.123

• . Heating of indole 9a with azirine 2a in the presence of 5 mol % of Ni(hfacac)2 afforded the desired annulation product 10 in 41% yield (Scheme 5). Unfortunately, we were unable to find conditions that allowed a similar reaction of NH-indole 9b to occur. At the same time, when Ni(hfacac)2 was replaced with

Azide–alkyne cycloaddition (click) reaction in biomass-derived solvent Cyrene^TM under one-pot conditions

• Zoltán Medgyesi and
• László T. Mika

Beilstein J. Org. Chem. 2025, 21, 1544–1551, doi:10.3762/bjoc.21.117

• capillary column (15 m × 0.25 mm × 0.25 µm) using H2 as a carrier gas. For the analysis, 10 μL of the reaction mixture was dissolved in 1 mL of ethyl acetate, followed by adding 10 μL toluene as the internal standard. Heating profile of GC–FID analysis: The initial temperature was 100 °C and was hold for

• 0.5 min. Heating rate: 40 °C/min up to the final temperature of 270 °C. The final temperature was held for 4.25 min. The water content of CyreneTM was measured on a Methrom 684 KF Coulometer at Balint Analitika Ltd, Budapest, Hungary. CyreneTM was purchased from Sigma-Aldrich Kft. Budapest, Hungary

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

• Grzegorz Mlostoń,
• Małgorzata Celeda,
• Marcin Palusiak,
• Heinz Heimgartner,
• Marta Denel-Bobrowska and
• Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

• regioselectivity in high yields. Upon heating to 65 °C in toluene solution, in analogy to the well-known compounds 2a and 2b, they extruded N2 and the in situ-generated reactive thiocarbonyl S-methanides 1c and 1d, in absence of any trapping reagent, underwent 1,3-dipolar electrocyclization yielding the

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

• reported in numerous green protocols, offer significant advantages over the use of conventional heating. The goal was to utilise selective, volumetric dielectric heating to save time and energy, enable selective catalysis and generally achieve higher selectivity and yields [53][55][56]. Building on the

• experiment confirms that MW irradiation activates the catalyst independently of bulk temperature, as reported in previous studies [57][58]. We can hypothesise that MW heating is likely associated with the generation of hot spots on metal sites, resulting in an accelerated reaction rate and improved

• . SIPERNAT 320 amorphous silica was supplied by Evonik. Reactions were monitored by TLC on Merck 60 F254 (0.25 mm) plates (Milan, Italy), which were visualised by UV inspection and/or by heating after spraying with 0.5% ninhydrin in ethanol or phosphomolybdic acid. Homogeneously catalysed reactions were

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

• alcohols 13 and a binary Al/TBAB catalyst (Scheme 5) [40]. The reaction is carried out in toluene upon mild heating, providing the bicyclic products in high to excellent yields. Both electron-rich and electron-poor phenyls as well as aliphatic chains worked well, however, increased temperature and catalyst

• under mildly basic conditions to prevent possible side-reactions, specifically iododesilylation and oxetane opening by the relatively nucleophilic succinimide. Attempts to prepare the bulkier 2,3,3,4,4-pentasubstitued oxetanes were unsuccessful due to very poor conversions (<5%) and heating those

• , anhydrous conditions and mild heating to afford the products in moderate to good yields. The reaction worked well for both aliphatic and aryl-substituted substrates but best results were obtained for shorter hydrocarbon side chains and 2,6-disubstituted phenyls. The authors demonstrated the applicability of

Recent advances in amidyl radical-mediated photocatalytic direct intermolecular hydrogen atom transfer

• Hao-Sen Wang,
• Lin Li,
• Xin Chen,
• Jian-Li Wu,
• Kai Sun,
• Xiao-Lan Chen,
• Ling-Bo Qu and
• Bing Yu

Beilstein J. Org. Chem. 2025, 21, 1306–1323, doi:10.3762/bjoc.21.100

• insight in the development of novel methods for amidyl radical-mediated photocatalytic direct intermolecular hydrogen atom transfer. Although, amidyl radicals employed in many reactions as HAT reagents via heating conditions have been summarized in several studies [52][53][54][55][56][57][58]. To advance

• effective, the use of heating conditions resulted in a higher yield of the corresponding products. This advancement prompted scientists to explore alternative pathways for generating amidyl radicals, as an alternative to the traditional SET reduction of the N–O bond [80][81][82]. The SET reduction is able

Recent advances and future challenges in the bottom-up synthesis of azulene-embedded nanographenes

• Bartłomiej Pigulski

Beilstein J. Org. Chem. 2025, 21, 1272–1305, doi:10.3762/bjoc.21.99

• (Scheme 24). Further heating on the Au(111) surface led to products with partial skeletal rearrangement, driven by intramolecular structural strain. Both nanographenes, 186 and 187, contain six formal azulene subunits and exhibit nearly planar geometry. However, theoretical analysis of NICS values

• -dibromoazulene (203) was annealed on an Au(111) surface, leading to the formation of 2,6-polyazulene chains 204. Upon heating these chains to 730 K, laterally fused chains were observed. The distinctive phagraphene nanoribbon 205 and the THP-graphene nanoribbon 206 were formed. This transformation provides solid

Selective monoformylation of naphthalene-fused propellanes for methylene-alternating copolymers

• Kenichi Kato,
• Tatsuki Hiroi,
• Seina Okada,
• Shunsuke Ohtani and
• Tomoki Ogoshi

Beilstein J. Org. Chem. 2025, 21, 1183–1191, doi:10.3762/bjoc.21.95

• heating process. T90 and CY of [3.3.3]_branch (415 °C and 64 wt %) were lower than those of [3.3.3]_linear because of two-step decay profile (Figure S703a in Supporting Information File 1). All the samples showed broad powder X-ray diffraction (PXRD) patterns with unclear peaks at around 2θ = 11° and 20

Synthetic approach to borrelidin fragments: focus on key intermediates

• Yudhi Dwi Kurniawan,
• Zetryana Puteri Tachrim,
• Teni Ernawati,
• Faris Hermawan,
• Ima Nurasiyah and
• Muhammad Alfin Sulmantara

Beilstein J. Org. Chem. 2025, 21, 1135–1160, doi:10.3762/bjoc.21.91

• )-configurations, respectively. The macrocyclization study of borrelidin was subsequently carried out using model compounds 155a and 155b (Scheme 24). Heating compound 155a in dichloromethane for 18 hours in the presence of 5 mol % Grubbs’ second generation catalyst yielded coupling product 156a and unreacted

• starting material 155a. Encouragingly, the addition of an extra 5 mol % of the catalyst followed by further heating for 28 hours successfully converted the remaining 155a into 156a, which was isolated in 54% yield. A trace amount of an unwanted dimer of 155a was also detected. In contrast, different

Gold extraction at the molecular level using α- and β-cyclodextrins

• Susana Santos Braga

Beilstein J. Org. Chem. 2025, 21, 1116–1125, doi:10.3762/bjoc.21.89

• processes with high energetic costs such as heating or applying high pressure. Seeking to find an eco-friendlier method to strip the gold from carbon, the Stoddart group investigated the use of α-CD in a series of tests at the laboratory scale in which suspensions of KAu(CN)2-loaded carbon (50 mg

On the photoluminescence in triarylmethyl-centered mono-, di-, and multiradicals

• Daniel Straub,
• Markus Gross,
• Mona E. Arnold,
• Julia Zolg and
• Alexander J. C. Kuehne

Beilstein J. Org. Chem. 2025, 21, 964–998, doi:10.3762/bjoc.21.80

• into the near-IR (λem = 780 nm, ϕ = 0.8% in toluene). While the ϕ of TTM-TTM is low, no photoluminescence has been reported for PTM-PTM. ΔEST of TTM-TTM is at −1.22 kcal mol−1 indicating a singlet ground state as well; however, the value is larger than for PTM-PTM, requiring heating to observe

Studies on the syntheses of β-carboline alkaloids brevicarine and brevicolline

• Benedek Batizi,
• Patrik Pollák,
• András Dancsó,
• Péter Keglevich,
• Gyula Simig,
• Balázs Volk and
• Mátyás Milen

Beilstein J. Org. Chem. 2025, 21, 955–963, doi:10.3762/bjoc.21.79

• achieved by a few-step transformation starting from brevicolline ((S)-1) isolated from natural sources (Scheme 2) [19]. When heating (S)-1 in benzoyl chloride, opening of the pyrrolidine ring and N-benzoylation occurred, resulting in compound 9. Debenzoylation of the latter to 10, followed by the catalytic

• 21 under extremely harsh conditions (100 °C, 130 bar), followed by N-acetylation gave a mixture of diastereomeric racemates 22, which was cyclized to a diastereomeric mixture of β-carboline derivatives 23. Heating of 23 in pivalic acid in the presence of a catalytic amount of trifluoroacetic acid

Harnessing tethered nitreniums for diastereoselective amino-sulfonoxylation of alkenes

• Shyam Sathyamoorthi,
• Appasaheb K. Nirpal,
• Dnyaneshwar A. Gorve and
• Steven P. Kelley

Beilstein J. Org. Chem. 2025, 21, 947–954, doi:10.3762/bjoc.21.78

• (Scheme 3A). The mesylate could be cleanly substituted with azide by heating substrate with excess NaN3 in DMSO (Scheme 3B). With an excess of Schwartz’s reagent, the carbonyl was cleanly reduced to give 1,3-oxazine 62. Contrary to what we had initially predicted from literature precedent, there was no

Synthesis and photoinduced switching properties of C₇-heteroatom containing push–pull norbornadiene derivatives

• Daniel Krappmann and
• Andreas Hirsch

Beilstein J. Org. Chem. 2025, 21, 807–816, doi:10.3762/bjoc.21.64

• formation of O-QC2 was achieved after 15 minutes (Supporting Information File 1). Next, thermally induced back-conversion to Q-NBD2 was attempted by heating the sample to 50 °C overnight. This process resulted in the initial formation of O-UnS2, followed by further rearrangement, consistent with the

• isomerizes into another species with prolonged irradiation. The formation of the same species was also observed while attempting the back-isomerization of O-QC2 to O-NBD2 at elevated temperatures. However, prolonged heating resulted in rearrangement to a 4th unidentified species. Clean recovery of O-NBD2

Asymmetric synthesis of fluorinated derivatives of aromatic and γ-branched amino acids via a chiral Ni(II) complex

• Maurizio Iannuzzi,
• Thomas Hohmann,
• Michael Dyrks,
• Kilian Haoues,
• Katarzyna Salamon-Krokosz and
• Beate Koksch

Beilstein J. Org. Chem. 2025, 21, 659–669, doi:10.3762/bjoc.21.52

• Schlenk vessels at a Schlenk unit/oil pump vacuum under nitrogen atmosphere. The stated reaction temperatures are the respective values of the silicone oil heating bath. All reactions were stirred with an electric magnetic stirrer. 1H, 13C, and 19F NMR spectra were measured at room temperature with a JEOL

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

• 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

• colorless crystals from the reaction between Et3N and CH2Cl2 at 100 °C in DMF. Subsequently, the corresponding α-aminophosphonate 35a was obtained by heating 36a with an equal amount of diethyl phosphite (Scheme 28b). Furthermore, when the reaction was carried out with CD2Cl2, the corresponding deuterated

• formaldehyde and ammonia in situ by heating [83]. Under these conditions, the water present in hydrated HMTA is sufficient for this hydrothermal decomposition to occur. On the other hand, an excess of ammonia must be added to the reaction mixture to shift the equilibrium towards the imine. Using this procedure

Deep-blue emitting 9,10-bis(perfluorobenzyl)anthracene

• Long K. San,
• Sebastian Balser,
• Brian J. Reeves,
• Tyler T. Clikeman,
• Yu-Sheng Chen,
• Steven H. Strauss and
• Olga V. Boltalina

Beilstein J. Org. Chem. 2025, 21, 515–525, doi:10.3762/bjoc.21.39

• reactions) Dry Mg turnings (excess) were added to an oven-dried 100 mL Schlenk flask and mechanically activated via stirring and heating. After 1 h, dry THF (20 mL) and 9,10-ANTH(Br)2 (84 mg, 0.25 mmol) were added. Several activation methods were tried (ultra sonic bath, careful heating, addition of I2

Synthesis of electrophile-tethered preQ₁ analogs for covalent attachment to preQ₁ RNA

• Laurin Flemmich and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 483–489, doi:10.3762/bjoc.21.35

• was observed, and the alcohol intermediate was isolated in pure form. In both cases, quantitative bromination was achieved by heating the compounds in concentrated aqueous hydrobromic acid, which after evaporation afforded the pure compounds 4b–d. To generate iodide 4e, alcohol 11 was isolated and

• 3b in almost quantitative yield. The bis(3-bromopropyl)-modified ligand 3c was generated by heating preQ1 together with bis(3-hydroxypropyl)amine. It is noteworthy that the amine exchange reaction is thought to proceed via a purine methide intermediate [11]. Subsequent treatment of the diol with