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

• and colleagues published a one-step synthesis of spirooxindole 2,2-disubstituted oxetanes 11 via an unprecedented addition/substitution cascade (Scheme 4) [39]. The protocol reacts readily available 3-hydroxyindolinones 9 with phenyl vinyl selenone (10) in aqueous KOH at room temperature and gives

• promoted by visible light at room temperature, requires no protecting atmosphere or additives, and the resulting polysubstituted oxetanes are obtained in moderate to good yields. Additional advantages include scalability and high chemoselectivity as various functional groups were tolerated, including

• oxetane sulphonyl fluorides can be conveniently prepared in 4 steps from 3-oxetanone and are sufficiently stable at room temperature and to air/moisture. The coupling proceeds upon gentle heating in the presence of K2CO3 as the only additive and affords the aminooxetanes in high yields, even for

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

• amount of Bu4NPF6 as the supporting electrolyte in a MeOH/TFE 11:1 (v/v) co-solvent mixture under blue LED irradiation at a constant current of 1.5 mA for 12 hours at room temperature. A wide range of substrates exhibited good functional group tolerance, with 3-homoallylquinazolin-4-ones bearing electron

• particularly noteworthy for its use at room temperature, requiring no transition metals, photocatalysts, or additives. Notably, Umemoto's reagent served as the trifluoromethyl source, and the reaction was facilitated under blue LED irradiation, achieving good to excellent yields. Moreover, this approach

• (4CzIPN), leading to either the reduction of sulfoxonium ylides to hydrocarbons or their participation in radical coupling with alkenes for carboarylation reactions. The reactions were carried out under mild, room temperature conditions using a DCM/H2O 1:2 solvent system. Various reaction conditions were

Optimized synthesis of aroyl-S,N-ketene acetals by omission of solubilizing alcohol cosolvents

• Julius Krenzer and
• Thomas J. J. Müller

Beilstein J. Org. Chem. 2025, 21, 1201–1206, doi:10.3762/bjoc.21.97

• -N-benzylbenzothiazolium salts in 1,4-dioxane at room temperature in short reaction time in 20–99% yield. This protocol represents a considerable improvement over the standard synthesis in 1,4-dioxane/ethanol mixtures at elevated temperatures. Keywords: aroyl chlorides; aroyl-S,N-ketene acetals

• , kinetic control is warranted by conducting the condensation synthesis at room temperature for only short reaction times. Furthermore, 2-MeTHF was successfully implemented as a sustainable alternative to 1,4-dioxane. This modified protocol is clearly superior to the initial protocol (in 1,4-dioxane/ethanol

• ) were placed in a sintered, dry screw-cap Schlenk-tube under nitrogen atmosphere and dissolved in dry 1,4-dioxane (30 mL). Triethylamine (1.52 mL, 11.0 mmol, 2.20 equiv) was added to the reaction mixture and the solution was stirred for 1 h at room temperature. The crude product was absorbed onto Celite

Synthesis of β-ketophosphonates through aerobic copper(II)-mediated phosphorylation of enol acetates

• Alexander S. Budnikov,
• Igor B. Krylov,
• Fedor K. Monin,
• Valentina M. Merkulova,
• Alexey I. Ilovaisky,
• Liu Yan,
• Bing Yu and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2025, 21, 1192–1200, doi:10.3762/bjoc.21.96

• stirred for 3 hours at 70 °C under air (air condenser) and then cooled to room temperature, and rotary-evaporated under reduced pressure. An additional evaporation step using a rotary vane pump (0.5 mmHg) at 80 °C was made for the evaporation of phosphite excess. The residue was isolated by column

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

• ) [55][56][63][64][65][66] yielded the monoformyl product [4.3.3]_CHO, in a selective manner (Table 1, entry 1). To suppress decomposition in the overnight reaction at room temperature, the reaction time was reduced to 1.5 h, which afforded [4.3.3]_CHO in an isolated yield of 80% (Table 1, entry 2). The

• electrophilic functionalization. a) Synthesis of methylene-alternating copolymers of fully π-fused propellanes. DCE, 1,2-dichloroethane. b) 1H NMR (500 MHz, top) and 13C (126 MHz, bottom) NMR spectra of [4.3.3]_CH2OH and [4.3.3]_linear in CDCl3 at room temperature. Gas adsorption (filled circles) and desorption

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

• in 89–98% yields. Reactions of 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-acylated compounds 6 in 80–90% yields [19]. With N-acylated GBB adducts 6 in hand, the synthesis of imidazopyridine-fused

• 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

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

• presence of DCC and DMAP. The reaction was allowed to proceed for 6 h at room temperature, after which the temperature was reduced to −10 °C, and sodium borohydride was added. The mixture was left to react for 12 hours, yielding compound 53 in 96%. This intermediate was then converted to acrylic acid 54 by

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

• 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

• ]triazolo[4,3-a]pyrazine (compound 1; Scheme 1) according to the approach previously described by Korsik et al. [10] was performed, but without reflux, in order to compare the yield obtained for the aminated product under our further modified conditions (neat phenethylamine only, room temperature; Scheme 1

• column chromatography (and additionally by HPLC for the toluene reaction), the reactions also gave comparable yields of compound 2 (70% for toluene/silica and 82% for only phenethylamine at room temperature). Only the tele-substituted product was observed in either reaction mixture, consistent with

A versatile route towards 6-arylpipecolic acids

• Erich Gebel,
• Cornelia Göcke,
• Carolin Gruner and
• Norbert Sewald

Beilstein J. Org. Chem. 2025, 21, 1104–1115, doi:10.3762/bjoc.21.88

• amount of water was added to activate the boronic species and to dissolve the inorganic base under otherwise inert conditions. The reaction mixture was then stirred at room temperature overnight. Under these conditions, a variety of boronic acids with different steric and electronic properties was

Salen–scandium(III) complex-catalyzed asymmetric (3 + 2) annulation of aziridines and aldehydes

• Linqiang Wang and
• Jiaxi Xu

Beilstein J. Org. Chem. 2025, 21, 1087–1094, doi:10.3762/bjoc.21.86

• procedure [16]. General procedure for the synthesis of ethyl 2-(oxazol-2-yl)alkanoates 3 Sc(OTf)3 (9.8 mg, 0.02 mmol) was added in a dried 10 mL reaction tube, then it was heated to 220 °C and dried at 220 °C for 2 h under oil pump vacuum. After gradually cooling to room temperature, the chiral salen ligand

• with a syringe and the mixture was stirred at 55 °C for 24 h. After gradually cooling to room temperature and removal of the solvent under reduced pressure, the crude residue was purified by basic aluminum oxide column chromatography with petroleum ether/ethyl acetate 1:10 to 3:7 (v/v) as eluent to

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

• excellent yield (Scheme 2) [32]. The formed anhydride 3 was smoothly converted to the amide at room temperature. This method provides a green approach by allowing cinnamic acid derivatization in water as a benign solvent. Similarly, Rajendran and Rajan (2023) reported a one-pot transamidation of cinnamamide

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

• problems in the future and prepare organic radicals for the challenges in emerging quantum technological applications. Review Triarylmethyl monoradicals The importance of symmetry in triarylmethyl radicals Gomberg’s radical is unstable at room temperature and dimerizes quickly to a closed-shell molecule

• mixture of right- and left-handed propellers can be resolved by chiral high pressure liquid chromatography (HPLC) into the P- and M-enantiomers, respectively [40][41]. However, due to the low racemization barrier of only about 22 kcal mol−1, the enantiomers racemize within minutes at room temperature. TTM

• )methyl (TTBrM) radical exhibits λem = 593 nm and ϕ of 0.8% (in dichloromethane-solution, at room temperature) [50][51]. Functionalization of TTM in the para-position has also been achieved with a pseudo-halide, namely a nitrile group. While the absorption and emission spectra are slightly

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

• equivalent of commercial iodomesitylene diacetate (CAS [33035-41-5]) and 1 equivalent of MsOH (Table 1, entry 4). Here, it was necessary to maintain a temperature of 0 °C, as vigorous bubbling and rapid decomposition occurred when the reaction was initiated at room temperature. In all cases (Table 1), only a

• delivering product (Table 2, entries 1 and 3–5). With our standard conditions of stirring substrate with 1.5 equivalents of PhI(OH)(OTs) in CH2Cl2 at room temperature, the yield of product markedly suffered with N-isopropoxy carbamate substrate 3 (Table 2, entry 2). Here, we hypothesize that the increased

Study of tribenzo[b,d,f]azepine as donor in D–A photocatalysts

• Katy Medrano-Uribe,
• Jorge Humbrías-Martín and
• Luca Dell’Amico

Beilstein J. Org. Chem. 2025, 21, 935–944, doi:10.3762/bjoc.21.76

• , with values of 16%, 14%, and 14%, respectively. The lowest values were obtained for molecules 5a and 5b (7% and 6%, each). Remarkably, compound 5e demonstrated minimal luminescence in nearly all solvents at room temperature. This behavior has been previously reported and is believed to be due to strong

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

• , when performed at room temperature, proceeded with lower efficiency compared to the reaction at 70 °C, leaving some of the starting 1H-pyrazole-3-carbaldehyde (14a) unreacted. Propargylamide 15a was selected as a model substrate to optimize the reaction conditions for the intramolecular

• pyrazole-tethered propargylamides 15 via U4CR. Conditions: Unless otherwise specified, the reactions were run on a 1.0 mmol scale in methanol (5 mL). The reactions were conducted in screw cap vials at 70 °C for 24 hours and isolated yields are reported. aConducted on a 6.0 mmol scale. bConducted at room

• temperature. cConducted on a 2.0 mmol scale. dConducted on a 1.5 mmol scale. Scope of the silver(I) triflate-catalyzed synthesis of pyrazolo[1,5-a][1,4]diazepines. Conditions: Unless otherwise specified, the reactions were run on 0.2 mmol scale using 20 mol % of AgOTf in dioxane (1 mL). The reactions were

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

• (cod)Cl]2 and the Carreira chiral phosphoramidite ligand (S)-L10, along with the addition of 3,5-dichlorobenzoic acid as an additive in MeOH at room temperature, the reaction proceeded smoothly for 10 hours to yield the aminated product 51. Interestingly, when the reaction was quenched after 6 minutes

• and n-BuLi, followed by a reaction with ZnCl2 at room temperature. The product is then hydrolyzed with a NaOH solution of H2O2 to yield amino alcohols. The mechanism involves the formation of borate intermediate Int-79 from substrate 83 under the action of CH2BrLi. This is followed by an N-1,2

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

• , the hydride addition of DIBAL-H to allene 1a catalyzed by 5 mol % IPrCuCl as the optimal catalyst selectively generated the allylaluminum intermediate 2a with >98% conversion [30]. Subsequent addition of one equivalent of TsCN to 2a in a single vessel at room temperature proceeded regioselectively

• scope for the formal hydrocyanation with 1,1-disubstituted and 1,1,3-trisubstituted allenes was examined (Scheme 3). All reactions were performed in the presence of 5 mol % IPrCuCl to generate the allylaluminum reagents in situ, followed by cyanation at room temperature for 30 min. This method

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

• undivided cell at room temperature, and three different electrodes, graphite, platinum, and glassy carbon (GC), were examined during the reaction. The best result was obtained when platinum electrodes were used as the anode and cathode. Although the reaction was less efficient in undivided cells, increasing

• electrochemical method. They have synthesized 30 different thiazole phosphine oxides with up to 91% yield at room temperature without using an external metal or oxidant. The reaction was carried out in an undivided cell using glassy carbon as the anode and foamed copper as the cathode electrodes at a constant

• et al. [59] reported an electrochemical method for the synthesis of phosphorylation of oxindoles and indolo[2,1-a]isoquinoline-6(5H)-ones using Cp2Fe through a radical addition/cyclization reaction at room temperature under argon gas. This research shows that this method is effective with various

Development and mechanistic studies of calcium–BINOL phosphate-catalyzed hydrocyanation of hydrazones

• Carola Tortora,
• Christian A. Fischer,
• Sascha Kohlbauer,
• Alexandru Zamfir,
• Gerd M. Ballmann,
• Jürgen Pahl,
• Sjoerd Harder and
• Svetlana B. Tsogoeva

Beilstein J. Org. Chem. 2025, 21, 755–765, doi:10.3762/bjoc.21.59

• BINOL phosphate/Ca(OiPr)2. In the presence of two equivalents of TMSCN, complex 4 gave a quantitative conversion to the product 2, whereby the phosphoric acid BIPO4-H ligand 3 did not catalyze this hydrocyanation. At room temperature, a nearly full conversion can already be achieved within 2–12 hours

Copper-catalyzed domino cyclization of anilines and cyclobutanone oxime: a scalable and versatile route to spirotetrahydroquinoline derivatives

• Qingqing Jiang,
• Xinyi Lei,
• Pan Gao and
• Yu Yuan

Beilstein J. Org. Chem. 2025, 21, 749–754, doi:10.3762/bjoc.21.58

• moderate yield (Table 1, entry 6). Conducting the reaction at room temperature (rt) instead of the optimal elevated temperature resulted in a lower yield (Table 1, entry 7). Increasing the reaction temperature to 100 °C did not improve the yield (Table 1, entry 8). Having established the optimal reaction

Synthesis of HBC fluorophores with an electrophilic handle for covalent attachment to Pepper RNA

• Raphael Bereiter and
• Ronald Micura

Beilstein J. Org. Chem. 2025, 21, 727–735, doi:10.3762/bjoc.21.56

• obtained in general procedure B was dissolved in dichloromethane and cooled to 0 °C under argon atmosphere. Then, triphenylphosphine and carbon tetrabromide were added and stirred at room temperature for two hours. Afterwards, the entire mixture was loaded on a silica gel column and eluted with 100

• % dichloromethane. General procedure D. In a manner similar to [11], the product obtained in general procedure B, methanesulfonyl chloride, and triethylamine were dissolved in dichloromethane and stirred overnight at room temperature. After reaction control and 100% consumption of the starting material, the entire

Acyclic cucurbit[n]uril bearing alkyl sulfate ionic groups

• Christian Akakpo,
• Peter Y. Zavalij and
• Lyle Isaacs

Beilstein J. Org. Chem. 2025, 21, 717–726, doi:10.3762/bjoc.21.55

• shows an ion at m/z = 751.13 which corresponds to [C1 − 2Na]2−. Inherent aqueous solubility of C1 After having firmly established the structure of C1 we decided to determine its inherent aqueous solubility. For this purpose, we added an excess of solid C1 to D2O and stirred the solution at room

• temperature overnight. Afterwards, the mixture was centrifuged (4400 rpm, 10 min) to pellet excess insoluble C1. An aliquot of the supernatant and a solution of dimethyl malonic acid as a non-binding internal standard of known concentration were transferred to an NMR tube followed by collection of a 1H NMR

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

• identified as optimal delivering a yield of alkylated complex of 60% (Table 1, entry 4). With DBU as base different solvents differing in polarity have been tested. At room temperature, acetonitrile proved best and increased the yield to 88% (Table 1, entry 11). Lowering the temperature to 0 °C led to a

• (II) complex of bisTfMePhe have differed significantly. Here, sodium hydride (NaH) was identified as optimal base leading to a yield of 85% when using DMF as solvent at 0 °C to room temperature (Table 2, entry 4). Testing different base equivalents, solvents, solvent mixtures and temperatures didn’t

• lead to any yield improvement (Table 2, entries 7–13). Herein, using dimethylformamide (DMF), different equiv of alkyl bromide were further screened resulting in a yield of 93%. Thus, 1.5 equiv NaH with 1.5 equiv alkyl bromide in DMF at 0 °C to room temperature have been identified as optimal

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

• optimization revealed LiOt-Bu and diphenyl phosphate as the optimal metal alkoxide and leaving group, delivering the desired product 32 in high yield and high enantioselectivity at room temperature with only 2 mol % catalyst loading. The scope of this transformation proved to be remarkably broad. In addition

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

• conditions at room temperature, and 2.0 F charge (if not otherwise noticed) with current density of 12 mA/cm2 was passed through the colorless reaction solution. The resulting clear, colorless (sometimes pale yellow) solution was concentrated under reduced pressure and the crude product was purified by