Structure and thermal stability of phosphorus-iodonium ylids

• Andrew Greener,
• Stephen P. Argent,
• Coby J. Clarke and
• Miriam L. O’Duill

Beilstein J. Org. Chem. 2024, 20, 2931–2939, doi:10.3762/bjoc.20.245

• , with the tosylate trans to the arene in one (θ2 = 177.8) and trans to the ylid in the other (θ1 = 169.5), which suggests that this isomerisation is fast at room temperature and the position of the anion has no significant effect on the stability of these compounds. This hypothesis is further supported

The charge transport properties of dicyanomethylene-functionalised violanthrone derivatives

• Sondos A. J. Almahmoud,
• Joseph Cameron,
• Dylan Wilkinson,
• Michele Cariello,
• Claire Wilson,
• Alan A. Wiles,
• Peter J. Skabara and
• Graeme Cooke

Beilstein J. Org. Chem. 2024, 20, 2921–2930, doi:10.3762/bjoc.20.244

• carbonate was added (300 mg, 2.04 mmol), and the reaction mixture was stirred at 100 °C overnight. After cooling the reaction mixture to room temperature, it was poured into methanol (200 mL), and the resulting precipitate was filtered, then washed with water (150 mL) to give the title compound as a dark

• mmol) and 1-bromooctane (2.12 mL, 12.28 mmol) were dissolved in N,N-dimethylformamide (60 mL). Then, potassium carbonate was added (1.13 g, 8.19 mmol), and the reaction mixture was stirred at 100 °C overnight. After cooling the reaction mixture to room temperature, it was poured into methanol (400 mL

• overnight. After cooling the reaction mixture to room temperature, it was poured into methanol (200 mL), and the resulting precipitate was filtered, then washed with water (150 mL) to give the title compound as a dark solid (600 mg, 71%). 1H NMR (400 MHz, CDCl3) δ 8.78 (d, J = 8.0 Hz, 2H), 8.63 (d, J = 8.3

Recent advances in transition-metal-free arylation reactions involving hypervalent iodine salts

• Ritu Mamgain,
• Kokila Sakthivel and
• Fateh V. Singh

Beilstein J. Org. Chem. 2024, 20, 2891–2920, doi:10.3762/bjoc.20.243

• group from position 4, and then regioselective vicinal functionalization of the generated aryne. The method's compatibility with halide-substituted aryl compounds enhances its versatility and practicality. Moreover, the completion of reaction within a mere 40 minutes at room temperature underscores its

• aryl donor (Scheme 24) [75]. The reaction worked very well at room temperature under base-free conditions. In this one-pot synthesis of double arylation of naphthols 58, a novel radical precursor, [1,1´-oxybis(2,2,6,6-tetramethylpiperidine)] (59), was employed. This precursor undergoes spontaneous

• of O3-arylated galactosides 64 by reacting benzyl-protected galactoside 63 with diphenyliodonium triflates 16 at room temperature in the presence of potassium tert-butoxide as the base (Scheme 26) [77]. This transition-metal-free approach simplifies the synthesis process. Electron-pushing and

C–H Trifluoromethylthiolation of aldehyde hydrazones

• Victor Levet,
• Balu Ramesh,
• Congyang Wang and
• Tatiana Besset

Beilstein J. Org. Chem. 2024, 20, 2883–2890, doi:10.3762/bjoc.20.242

• room temperature. α,α,α-Trifluoroacetophenone (42 μL, 0.3 mmol, 1.0 equiv) was added as an internal standard for determining the 19F NMR yield. The mixture was then filtered on a pad of celite and rinsed with CH2Cl2. The solution was then washed with brine twice (20 mL) and the organic layers were

Synthesis of pyrrole-fused dibenzoxazepine/dibenzothiazepine/triazolobenzodiazepine derivatives via isocyanide-based multicomponent reactions

• Marzieh Norouzi,
• Mohammad Taghi Nazeri,
• Ahmad Shaabani and
• Behrouz Notash

Beilstein J. Org. Chem. 2024, 20, 2870–2882, doi:10.3762/bjoc.20.241

• , we investigated the reaction in dichloromethane at room temperature and at 40 °C (Table 1, entries 1 and 2) and we found that the reaction progressed slightly at 40 °C. This promising result prompet us to examine the reaction in multiple anhydrous solvents such as CH3CN, toluene, EtOH, THF, EtOAc

• studied by X-ray diffraction analysis, and the crystal structure is illustrated in Figure 2 (detailed information can be found in the Supporting Information File 1). The 1H NMR spectrum of product 6f obtained through the I-MCR was investigated and some unexpected chemical shifts were observed at room

• temperature (Figure 3A) [46]. Therefore, dynamic NMR measurements were performed for compound 6f at various temperatures (25, 35, 45, 55, 65, 75, and 85 °C). As illustrated in Figure 3, all peaks in the spectrum correspond to the structure of 6f. Spectrum A recoreded at 25 °C has two broad singulet signals at

Multicomponent synthesis of α-branched amines using organozinc reagents generated from alkyl bromides

• Baptiste Leroux,
• Alexis Beaufils,
• Federico Banchini,
• Olivier Jackowski,
• Alejandro Perez-Luna,
• Fabrice Chemla,
• Marc Presset and
• Erwan Le Gall

Beilstein J. Org. Chem. 2024, 20, 2834–2839, doi:10.3762/bjoc.20.239

• ]. Thus, whereas Rieke et al. reported the insertion of activated zinc into alkyl bromides in THF at room temperature [16][17], Knochel et al. described the direct metalation of alkyl iodides in THF at 30 °C [18]. More recently, Knochel et al. improved their original method by the use of zinc dust in the

• presence of LiCl in THF for the metalation of alkyl bromides at room temperature [19]. Besides, Huo described the insertion of zinc dust into alkyl bromides at 80 °C in DMA or DMF [20]. Despite the high synthetic interest in mixed organozinc compounds, their use in the preparation of α-branched amines

Synthesis of tricarbonylated propargylamine and conversion to 2,5-disubstituted oxazole-4-carboxylates

• Kento Iwai,
• Akari Hikasa,
• Kotaro Yoshioka,
• Shinki Tani,
• Kazuto Umezu and
• Nagatoshi Nishiwaki

Beilstein J. Org. Chem. 2024, 20, 2827–2833, doi:10.3762/bjoc.20.238

• to that reported in reference [23], to a solution of DEMO (1.72 g, 10.0 mmol) in toluene (40 mL) were added 4-methylbenzamide (1.63 g, 12 mmol), 3 Å molecular sieves (3.4 g), and acetic anhydride (2.0 mL, 20 mmol). The resulting solution was heated at 100 °C for 4 h. After cooling to room temperature

• was reacted with lithium acetylide, which was prepared from ethynylbenzene (3a) and butyllithium at 0 °C, the solution turned black, resulting in a complex reaction mixture (Table 1, entry 1). This complication persisted even when the reaction was conducted at −78 °C and then warmed to room

• temperature without addition of acetic acid. To address this, the reaction was performed at −78 °C, and acetic acid was added at the same temperature, yielding adduct 4a in 13% yield (Table 1, entry 2). The reaction yield was significantly influenced by the amounts of 3a and butyllithium used. The yield of 4a

Investigation of a bimetallic terbium(III)/copper(II) chemosensor for the detection of aqueous hydrogen sulfide

• Parvathy Mini,
• Michael R. Grace,
• Genevieve H. Dennison and
• Kellie L. Tuck

Beilstein J. Org. Chem. 2024, 20, 2818–2826, doi:10.3762/bjoc.20.237

• were measured at room temperature utilizing a Varian Cary 1E UV–vis spectrophotometer with a quartz cell of 10 mm path length. Luminescence emission spectra of aqueous solutions were captured at 23 °C using a Varian Cary-Eclipse fluorescence spectrophotometer set to phosphorescence mode, employing a

• calibration gas generator. Synthesis of Tb.1 To a solution of L (155 mg, 0.5 mmol) in water (6 mL) and 1 M NaOH (4 mL) a solution of Tb(OTf)3 (100 mg, 0.166 mmol) in water (2 mL) was added to obtain a white precipitate instantly. The solution was stirred at room temperature for a day. The precipitate was

Mechanochemical difluoromethylations of ketones

• Jinbo Ke,
• Pit van Bonn and
• Carsten Bolm

Beilstein J. Org. Chem. 2024, 20, 2799–2805, doi:10.3762/bjoc.20.235

• efficiently converted to the target products under solvent-free conditions. The reactions proceed at room temperature and are complete within 90 minutes, demonstrating both efficiency and experimental simplicity. Keywords: ball milling; difluorocarbene; difluoromethylations; difluoromethyl enol ether

• reaction conditions were chosen based on those reported by Ni, Hu and co-workers for the difluoromethylation of alcohols in solution [39]. The two activators KFHF and KOAc were investigated in a dichloromethane/water mixture at room temperature for 10 h. In both cases, the yield of 3a was negligible (with

• during the reaction. Conclusion In conclusion, we discovered a mechanochemical synthesis of difluoromethyl enol ethers. The products were obtained from the corresponding ketones at room temperature after a reaction time of 90 minutes. The investigation of the reaction scope revealed challenges in

Access to optically active tetrafluoroethylenated amines based on [1,3]-proton shift reaction

• Yuta Kabumoto,
• Eiichiro Yoshimoto,
• Bing Xiaohuan,
• Masato Morita,
• Motohiro Yasui,
• Shigeyuki Yamada and
• Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2776–2783, doi:10.3762/bjoc.20.233

• Science and Engineering, Ibaraki University, 4-12-1 Nakanarusawa, Hitachi, Ibaraki 316-8511, Japan 10.3762/bjoc.20.233 Abstract Treatment of various (R)-N-(2,2,3,3-tetrafluoropent-4-en-1-ylidene)-1-phenylethylamine derivatives with 2.4 equiv of DBU in toluene at room temperature to 50 °C for 24 h led to

• at room temperature for 24 h gave the corresponding [1,3]-proton shift adduct (S)-20b in 31% yield (Table 1, entry 1). In this case, the HF-elimination product 21b was also obtained in 16% [37], and the starting material was recovered in 53%. As shown in entries 2–7 of Table 1, the reactions in

Copper-catalyzed yne-allylic substitutions: concept and recent developments

• Shuang Yang and
• Xinqiang Fang

Beilstein J. Org. Chem. 2024, 20, 2739–2775, doi:10.3762/bjoc.20.232

• for the Cu(I) system indicate that it is not the formation of alkynyl copper intermediate but the formation of active copper vinyl allenylidene intermediate is the rate-limiting step (Scheme 10). Due to the gaseous nature of dimethylamine at room temperature, it needs to be stored in special solvents

Interaction of a pyrene derivative with cationic [60]fullerene in phospholipid membranes and its effects on photodynamic actions

• Hayato Takagi,
• Çetin Çelik,
• Ryosuke Fukuda,
• Qi Guo,
• Tomohiro Higashino,
• Hiroshi Imahori,
• Yoko Yamakoshi and
• Tatsuya Murakami

Beilstein J. Org. Chem. 2024, 20, 2732–2738, doi:10.3762/bjoc.20.231

• until the lipid membrane had completely peeled off from the flask. To remove free catC60 and C60, the resulting suspension was centrifuged at 20,000g at room temperature for 10 min. The supernatant was collected and subjected to more than 20 extrusions using a Mini-Extruder equipped with a 100 nm-pore

• solution (335 µM) was added instead of 10 µM of PBS(–). The solution was subjected to O2 bubbling for 30 seconds and then taken into 50 µL capillary and sealed. The solution was then irradiated with blue LED light for 30 minutes. The capillary was taken into the ESR tube for measurement at room temperature

• recorded at room temperature. O2•– Generation: Measurements were performed in a mixture of DMSO and PBS(–) (1-to-4, v/v). Ten µL of catC60 sample solution (25 µM), 10 µL of DETAPAC solution (5 mM), 10 µL of DEPMPO solution (500 mM), 10 µL of NADH (40 mM) and 10 µL of PBS(–) were mixed in a 0.5 mL Eppendorf

Synthesis of spiroindolenines through a one-pot multistep process mediated by visible light

• Francesco Gambuti,
• Jacopo Pizzorno,
• Chiara Lambruschini,
• Renata Riva and
• Lisa Moni

Beilstein J. Org. Chem. 2024, 20, 2722–2731, doi:10.3762/bjoc.20.230

• of components and temperature (Table 2). We firstly irradiated with blue LEDs (451 nm) the mixture of the three components in the presence of 1.5 equiv of BrCCl3 for 18 h at room temperature under argon atmosphere (Table 2, entry 1). To our surprise, the reaction provided only traces of the expected

5th International Symposium on Synthesis and Catalysis (ISySyCat2023)

• Anthony J. Burke and
• Elisabete P. Carreiro

Beilstein J. Org. Chem. 2024, 20, 2704–2707, doi:10.3762/bjoc.20.227

• in MeOH at room temperature with a short reaction time. Some of them were further functionalized with a 1,2,3-triazole ring via copper-catalyzed azide–alkyne cycloaddition (CuAAC) and deprotected with trifluoroacetic acid. Several hybrids were evaluated against six cancer cell lines, displaying GI50

Synthesis of fluoroalkenes and fluoroenynes via cross-coupling reactions using novel multihalogenated vinyl ethers

• Yukiko Karuo,
• Keita Hirata,
• Atsushi Tarui,
• Kazuyuki Sato,
• Kentaro Kawai and
• Masaaki Omote

Beilstein J. Org. Chem. 2024, 20, 2691–2703, doi:10.3762/bjoc.20.226

• (4 mol %) and triethylamine (1.5 equiv) in THF (2.5 mL) was added the respective alkyne 5 (2.0 equiv). The reaction solution was stirred at room temperature until 1 was disappeared. The reaction mixture was evaporated and concentrated under reduced pressure. The residue was purified by column

Photoluminescence color-tuning with polymer-dispersed fluorescent films containing two fluorinated diphenylacetylene-type fluorophores

• Kazuki Kobayashi,
• Shigeyuki Yamada,
• Motohiro Yasui and
• Tsutomu Konno

Beilstein J. Org. Chem. 2024, 20, 2682–2690, doi:10.3762/bjoc.20.225

• diphenylacetylene structure as the π-conjugated core. As a part of our research projects, we have begun to explore diphenylacetylene-based luminescent molecules despite diphenylacetylene not exhibiting fluorescence at room temperature because it undergoes a πσ* excited state that rapidly forms a trans-bend

Transition-metal-free decarbonylation–oxidation of 3-arylbenzofuran-2(3H)-ones: access to 2-hydroxybenzophenones

• Bhaskar B. Dhotare,
• Seema V. Kanojia,
• Chahna K. Sakhiya,
• Amey Wadawale and
• Dibakar Goswami

Beilstein J. Org. Chem. 2024, 20, 2655–2667, doi:10.3762/bjoc.20.223

• elemental analyses were carried out with an Elementar Vario micro cube. Generation of hydroperoxide in THF. 35 mL of freshly distilled THF were heated under open atmosphere at 50 °C for 4 h. After 4 h, it was allowed to cool to room temperature, and THF was removed by distillation under vacuum to obtain the

• mmol) and mandelic acid derivatives 2a–d (6 mmol) was stirred and heated to 50 °C under nitrogen atmosphere until the mixture turned into a viscous oil. The viscous oil/paste was further heated to 140 °C until the reaction was complete (cf. TLC). The mixture was then brought to room temperature and a

• reaction (3–4 h, cf. TLC), the mixture was cooled to room temperature and THF present in the reaction mixture was evaporated. The residue was purified by preparative TLC (hexane/EtOAc) to obtain pure 2-hydroxybenzophenones. Cautions must be taken during the synthesis of 2-hydroxybenzophenones, since THF

The scent gland composition of the Mangshan pit viper, Protobothrops mangshanensis

• Jonas Holste,
• Paul Weldon,
• Donald Boyer and
• Stefan Schulz

Beilstein J. Org. Chem. 2024, 20, 2644–2654, doi:10.3762/bjoc.20.222

• room temperature for 1 h. The solvent was removed with a stream of N2 and the sample was taken up in CH2Cl2 and analyzed by GC–MS [43]. Dimethyl disulfide derivatization: Twenty µL of the sample in a 2 mL GC vial were diluted with pentane (20 µL) and mixed with freshly distilled dimethyl disulfide

• . The extract was concentrated by slow evaporation at room temperature before analysis. Derivatization with 2-amino-2-methyl-1-propanol (DMOX derivatives): 2-Amino-2-methyl-1-propanol (50 µL) was added to the natural extract (100 µL) in a 2 mL GC vial. The vial was purged with N2 and heated to 120 °C

• for 18 h. After cooling down to room temperature, water, and diethyl ether were added. The phases were separated and the aqueous phase was extracted three times with diethyl ether. The organic phases were combined, dried over sodium sulfate, filtered, and concentrated for GC–MS analysis [44

Efficient modification of peroxydisulfate oxidation reactions of nitrogen-containing heterocycles 6-methyluracil and pyridine

• Alfiya R. Gimadieva,
• Yuliya Z. Khazimullina,
• Aigiza A. Gilimkhanova and
• Akhat G. Mustafin

Beilstein J. Org. Chem. 2024, 20, 2599–2607, doi:10.3762/bjoc.20.219

• determined that room temperature is inadequate for fully oxidizing substrates. The optimal oxidation temperature for uracils 1 and 4 is between 60–65 °C, whereas for pyridines 7 and 9 it is 45 °C. Heating the reaction mixture at a temperature higher than the optimum level causes the substrates to be

• mixture to room temperature, concentrated H2SO4 was slowly added until pH 6–7 according to litmus paper and left standing for 12 h. The precipitated white crystals were filtered off, washed with water, and dried in air. Compound 2 yields are given in [13] and compound 5 yields are given in Table 1. b

• at 45 °C for 10 h, cooled to room temperature, evaporated at reduced pressure to 1/3 volume, extracted with ethyl acetate (2 × 20 mL) to remove unreacted pyridine, followd by butanol (3 × 50 mL). The butanol fractions were combined and evaporated to dryness. The residue was washed with hot ethanol

Synthesis and cytotoxicity studies of novel N-arylbenzo[h]quinazolin-2-amines

• Battini Veeraiah,
• Kishore Ramineni,
• Dabbugoddu Brahmaiah,
• Nangunoori Sampath Kumar,
• Hélène Solhi,
• Rémy Le Guevel,
• Chada Raji Reddy,
• Frédéric Justaud and
• René Grée

Beilstein J. Org. Chem. 2024, 20, 2592–2598, doi:10.3762/bjoc.20.218

• bromobenzene (0.384 mmol, 1.5 equiv), Xanthphos (0.051 mmol, 0.2 equiv) and cesium carbonate (0.769 mmol, 3 equiv). This mixture was degassed for 15 minutes under N2 atmosphere. Pd2(dba)3 (0.0256 mmol, 0.1 equiv) was added and the reaction mixture was stirred for 16 h at 100 °C. After cooling to room

• temperature, the mixture was filtered through Celite and washed with EtOAc (2 × 10 mL). The filtrate was evaporated under reduced pressure and the crude product was purified by using 60–120 silica mesh column chromatography using 10–20% ethyl acetate in hexane as eluent afforded target compound 4a (69% yield

Base-promoted cascade recyclization of allomaltol derivatives containing an amide fragment into substituted 3-(1-hydroxyethylidene)tetronic acids

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

Beilstein J. Org. Chem. 2024, 20, 2585–2591, doi:10.3762/bjoc.20.217

• of the process time led to decrease of the yield due to partial tarring of the reaction mixture (Table 1, entry 3). Next, we assumed that the investigated reaction can be performed at room temperature. However, stirring under these conditions for 3 h in MeCN didn’t enhance the yield of compound 4a

• (Table 1, entry 7). Then, we tested the investigated reaction in various solvents at room temperature for 24 h. It should be noted that all solvents used had no advantage over MeCN (Table 1, entries 8–11). Thus, the best results for considered recyclization were achieved at stirring of amide 4a in the

• presence of CDI and DBU in MeCN at room temperature for 24 h. The aforementioned optimal conditions were utilized for the synthesis of a wide range of tetronic acids bearing a pyrrolidinone unit (Scheme 3). The presented protocol is of general nature and allows us to prepare the final products with various

A review of recent advances in electrochemical and photoelectrochemical late-stage functionalization classified by anodic oxidation, cathodic reduction, and paired electrolysis

• Nian Li,
• Ruzal Sitdikov,
• Ajit Prabhakar Kale,
• Joost Steverlynck,
• Bo Li and
• Magnus Rueping

Beilstein J. Org. Chem. 2024, 20, 2500–2566, doi:10.3762/bjoc.20.214

• anode and a foamed Ni cathode, at a constant current of 12 mA in DMSO at room temperature under atmospheric conditions. The reaction has been applied to more than 80 examples, including the late-stage functionalization of natural products and pharmaceuticals, as well as the synthesis and radiosynthesis

• method for the regioselective thiolation of aromatic C–H bonds by activating the thiol rather than the arene [19]. For their developed reaction, Pt electrodes were used in an undivided cell with a mixture of HFIP/DCE 3:1 at room temperature under argon. Late-stage functionalization was demonstrated for

HFIP as a versatile solvent in resorcin[n]arene synthesis

• Hormoz Khosravi,
• Valeria Stevens and
• Raúl Hernández Sánchez

Beilstein J. Org. Chem. 2024, 20, 2469–2475, doi:10.3762/bjoc.20.211

• set at 50% probability level. Resorcin[n]arene synthesis. Scope of resorcin[n]arene synthesis using HFIP. aAll reactions were performed with resorcinol (1.0 mmol), aldehyde (1.0 mmol), and HCl (30 mol %) in HFIP (5 mL) at room temperature, and the yields of the reactions are given as isolated yields

Phenylseleno trifluoromethoxylation of alkenes

• Clément Delobel,
• Armen Panossian,
• Gilles Hanquet,
• Frédéric R. Leroux,
• Fabien Toulgoat and
• Thierry Billard

Beilstein J. Org. Chem. 2024, 20, 2434–2441, doi:10.3762/bjoc.20.207

• stirred at room temperature for 2.5 h (unless otherwise stated). Note that a yellowish precipitate is formed during the reaction for high yielding substrates. The reaction is monitored by 19F NMR (PhCF3 as internal standard). At the end of the reaction, the content of the vial is transferred to a

Facile preparation of fluorine-containing 2,3-epoxypropanoates and their epoxy ring-opening reactions with various nucleophiles

• Yutaro Miyashita,
• Sae Someya,
• Tomoko Kawasaki-Takasuka,
• Tomohiro Agou and
• Takashi Yamazaki

Beilstein J. Org. Chem. 2024, 20, 2421–2433, doi:10.3762/bjoc.20.206

• indicated DMSO as the best for the attainment of high yields and diastereoselectivity (entries 1–5 vs 6 in Table 4), we further examined bases in this solvent to find out that t-BuOK behaved nicely, and the reaction of 2b with 2.0 equiv of diethyl malonate for 0.5 h at room temperature furnished 93% yield

• of compound 1b [42] (0.23 g, 1.00 mmol) in 3.0 mL of CH3CN was added NaClO aq. (5% in H2O, 1.50 g, 1.00 mmol) and the solution was stirred for 4.5 h at room temperature. This mixture was extracted with CH2Cl2 and the usual workup and purification afforded 0.15 g (0.60 mmol) of the pure title compound

• room temperature. Then, 0.1477 g (0.60 mmol) of 2b in 0.8 mL of DMSO was introduced to the resultant solution and the stirring was continued for 0.5 h. The same workup process and purification furnished 0.1717 g of an inseparable mixture of anti,syn-7a (dr = 99:1) and anti,syn-7b (7a:7b = 83:17). Anti