Synthesis of new condensed naphthoquinone, pyran and pyrimidine furancarboxylates

• Kirill A. Gomonov,
• Vasilii V. Pelipko,
• Igor A. Litvinov,
• Ilya A. Pilipenko,
• Anna M. Stepanova,
• Nikolai A. Lapatin,
• Ruslan I. Baichurin and
• Sergei V. Makarenko

Beilstein J. Org. Chem. 2025, 21, 340–347, doi:10.3762/bjoc.21.24

• -nitroacrylates 1a,b with 2-hydroxynaphthalene-1,4-dione (2a). The reaction proceeds successfully in a methanol solution in the presence of AcOK for 3 h at room temperature, resulting in the formation of a mixture of alkyl 4,9-dioxo-4,9-dihydronaphtho[2,3-b]furan-3-carboxylate 3a,b and alkyl 4,5-dioxo-4,5

• -c]chromene-3-carboxylates 5a,b with a yield of 84–85% were obtained under the same conditions as a result of the interaction of bromonitroacrylates 1a,b with 4-hydroxy-7,7-dimethyl-7,8-dihydro-2H-chromene-2,5(6H)-dione (2b) (ratio acrylate/CH-acid/AcOK = 1:1:1.5, room temperature, 1 h) (Scheme 5

• Shimadzu UV-2401 PC spectrometer for samples in DMSO solutions in fused quartz cuvettes (optical path length 1.01 mm). Luminescence excitation spectra and luminescence spectra were recorded on a Shimadzu SF-6000 spectrofluorimeter in a 1 cm thick quartz cuvette at room temperature in a DMSO solution (c

Antibiofilm and cytotoxic metabolites from the entomopathogenic fungus Samsoniella aurantia

• Rita Toshe,
• Syeda J. Khalid,
• Blondelle Matio Kemkuignou,
• Esteban Charria-Girón,
• Paul Eckhardt,
• Birthe Sandargo,
• Kunlapat Nuchthien,
• J. Jennifer Luangsa-ard,
• Till Opatz,
• Hedda Schrey,
• Sherif S. Ebada and
• Marc Stadler

Beilstein J. Org. Chem. 2025, 21, 327–339, doi:10.3762/bjoc.21.23

• mm, were inoculated with rice in 10 × 1 L Erlenmeyer flasks, each containing 180 g of rice and 180 mL of distilled water that were foremost autoclaved, and the mixture was incubated for 16 days under static conditions at room temperature until full mycelial growth was achieved. Upon reaching optimal

Molecular diversity of the reactions of MBH carbonates of isatins and various nucleophiles

• Zi-Ying Xiao,
• Jing Sun and
• Chao-Guo Yan

Beilstein J. Org. Chem. 2025, 21, 286–295, doi:10.3762/bjoc.21.21

• was found that the reaction did not proceed in DMF as solvent (Table 1). When the reaction was carried out in dichloromethane, dichloroethane, acetonitrile, and toluene, the expected product 3a was produced in low yields (entries 2–5 in Table 1). The reaction in toluene at elevated temperature

• resulted in a slight increase of the yield (entries 6 and 7 in Table 1). In the presence of 20 mol % of DMAP, the reaction in toluene at room temperature afforded the product 3a in 72% yield. However, increasing the amount of DMAP decreased the yield (entries 8–10 in Table 1). Additionally, stronger bases

• such as DABCO, DBU, triethylamine, and K2CO3 also resulted in the significant reduction of the yields. Therefore, the reaction of MBH nitrile of isatins and arylamines can be simply carried out in toluene at room temperature in the presence of a catalytic amount of DMAP. With the optimized reaction

Oxidation of [3]naphthylenes to cations and dications converts local paratropicity into global diatropicity

• Abel Cárdenas,
• Zexin Jin,
• Yong Ni,
• Jishan Wu,
• Yan Xia,
• Francisco Javier Ramírez and
• Juan Casado

Beilstein J. Org. Chem. 2025, 21, 277–285, doi:10.3762/bjoc.21.20

• , Me: methyl). Cyclic voltammograms of 1 and 2. UV–vis–NIR electronic absorption spectra of 1 (top) and 2 (bottom) during the electrochemical oxidation in 0.1 M n-Bu4N·PF6 in CH2Cl2 at room temperature. The traces are black lines for neutral, blue lines for radical cation, and red lines for dication

Three-component reactions of conjugated dienes, CH acids and formaldehyde under diffusion mixing conditions

• Dmitry E. Shybanov,
• Maxim E. Kukushkin,
• Eugene V. Babaev,
• Nikolai V. Zyk and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2025, 21, 262–269, doi:10.3762/bjoc.21.18

• generate crotonic condensation adducts of active methylene compounds and formaldehyde at room temperature in the absence of strong acids and bases. The formed adducts were highly reactive intermediates capable of reacting with dienes in a three-component reaction, leading to the formation of Diels–Alder

• –Alder products were isolated from the reaction mixtures. In the present study, we carried out similar three-component reactions under significantly milder conditions (room temperature), and the main or only [4 + 2]-cycloaddition products in most cases were carbocyclic ones. Results and Discussion

• in a high yield in the presence of ʟ-proline could be explained by the efficient crotonic condensation of formaldehyde and acetylacetone (1), followed by the addition of the second equivalent of diketone 1 to the highly reactive methylidene intermediate. The mild reaction conditions (room temperature

Synthesis of disulfides and 3-sulfenylchromones from sodium sulfinates catalyzed by TBAI

• Zhenlei Zhang,
• Ying Wang,
• Xingxing Pan,
• Manqi Zhang,
• Wei Zhao,
• Meng Li and
• Hao Zhang

Beilstein J. Org. Chem. 2025, 21, 253–261, doi:10.3762/bjoc.21.17

• reaction temperature resulted in a significant decrease in the yield (Table 1, entry 16) and at 80 °C no desired product, but only thiosulfonate was formed (Table 1, entry 17). The reaction did not proceed in the absence of acid or catalyst (Table 1, entries 18 and 19). Compared to TBAI, other iodized

• reacted with 3aa to form 4a and HI. However, under high-temperature conditions, C also reacted with HI to yield D and E. The latter was then oxidized to form 2a, while D was regenerated to A by reaction with HI. Hypoiodous acid underwent a reaction to complete the cycle of iodide ions by decomposing to

Effect of substitution position of aryl groups on the thermal back reactivity of aza-diarylethene photoswitches and prediction by density functional theory

• Misato Suganuma,
• Daichi Kitagawa,
• Shota Hamatani and
• Seiya Kobatake

Beilstein J. Org. Chem. 2025, 21, 242–252, doi:10.3762/bjoc.21.16

• which the photogenerated isomers are thermally unstable at room temperature and return to the initial isomers not only by photoreaction but also by the thermal back reaction, are utilized for eyeglass lenses [43], security inks [44], and real-time holograms [45]. Especially, it is important to control

• to N1(c)–N4(c), which is due to the localization of the π conjugation in the central part of the molecular skeleton as reported in inverse-type diarylethenes [64]. Figure 1c and the video (Supporting Information File 2) show the photochromic behavior of N4 at room temperature in n-hexane. It was

• and the rate constants (k) of the thermal back reactions at various temperatures were determined (Figure 2b,e and Supporting Information File 1, Figure S3 and Tables S1–S6). Figure 2c and 2f, and Figure S4 in Supporting Information File 1 show the temperature dependence of k (Eyring plots) for

Visible-light-promoted radical cyclisation of unactivated alkenes in benzimidazoles: synthesis of difluoromethyl- and aryldifluoromethyl-substituted polycyclic imidazoles

• Yujun Pang,
• Jinglan Yan,
• Nawaf Al-Maharik,
• Qian Zhang,
• Zeguo Fang and
• Dong Li

Beilstein J. Org. Chem. 2025, 21, 234–241, doi:10.3762/bjoc.21.15

• reaction (Table 1). Employing PIDA as the promoter, THF as the solvent, and 72 W white LED as the light source, the desired product 3a formed in 85% isolated yield at room temperature (Table 1, entry 1). We found that the hypervalent iodine reagent was of significant importance for the present

• . Reaction conditions: 1 (0.2 mmol), 2 (1.4 mmol), and PIDA (0.8 mmol) in solvent (2 mL) irradiated with 72 W white LEDs at room temperature for 12 h under a N2 atmosphere. Yields refer to isolated yield. aα,α-Difluorobenzeneacetic acid (2 equiv) was used. Control experiments and plausible mechanism

Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• and a catalytic amount of triethylamine were used in dichloromethane with careful control of the reaction temperature at 15 °C (Table S2, Supporting Information File 1). With the 2,3-diaminobenzofuran 11 in hand as the designed cyclization precursor, we explored the construction of the left

Heteroannulations of cyanoacetamide-based MCR scaffolds utilizing formamide

• Marios Zingiridis,
• Danae Papachristodoulou,
• Despoina Menegaki,
• Konstantinos G. Froudas and
• Constantinos G. Neochoritis

Beilstein J. Org. Chem. 2025, 21, 217–225, doi:10.3762/bjoc.21.13

• temperature and severe weather patterns – a result of human-induced greenhouse gas emissions. The principle of net-zero revolves around the idea of using Earth’s carbon resources at a rate that does not exceed their natural replenishment. In 2015, the United Nations introduced the Sustainable Development

Nickel-catalyzed cross-coupling of 2-fluorobenzofurans with arylboronic acids via aromatic C–F bond activation

• Takeshi Fujita,
• Haruna Yabuki,
• Ryutaro Morioka,
• Kohei Fuchibe and
• Junji Ichikawa

Beilstein J. Org. Chem. 2025, 21, 146–154, doi:10.3762/bjoc.21.8

• approach to complex molecule synthesis. Despite considerable efforts to develop various catalytic systems, the activation of aromatic C–F bonds often requires high temperatures [1][2][3][4][5][6][7]. Therefore, methods for activating aromatic C–F bonds at ambient temperature remain underdeveloped. We have

• (Scheme 1c). In this study, we demonstrate nickel-catalyzed defluorinative cross-coupling [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37] of 2-fluorobenzofurans 1 with arylboronic acids 2 at ambient temperature, with nickelacyclopropanes E serving as crucial intermediates for the

• catalyst, PCy3 (20 mol %) as a ligand, and K2CO3 (2.0 equiv) as a base, the desired arylated naphthofuran 3bb was obtained in 75% yield (Table 1, entry 1). Reducing the reaction temperature improved the yield of 3bb, reaching a quantitative yield when the reaction was performed at room temperature (Table 1

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

• cascade reaction for the preparation of α-alkoxy-N-alkyltriazoles 44 that was developed starting from aliphatic aldehydes, alcohols, TMSN3 as azide source and alkynes (Scheme 33) [52]. The reaction occurs under mild conditions in acetonitrile at room temperature but is inhibited when using aromatic

Recent advances in organocatalytic atroposelective reactions

• Henrich Szabados and
• Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

Hot shape transformation: the role of PSar dehydration in stomatocyte morphogenesis

• Remi Peters,
• Levy A. Charleston,
• Karinan van Eck,
• Teun van Berlo and
• Daniela A. Wilson

Beilstein J. Org. Chem. 2025, 21, 47–54, doi:10.3762/bjoc.21.5

• , as temperature is a factor in the van ‘t Hoff formula for osmotic pressure [21]. Additionally, dehydration strengthens polysarcosine chains interactions [16], potentially rendering the membrane too rigid for shape transformation. This means that the heating of the vesicles made with polysarcosine

• addition water – this process was facilitated by the glass-transition temperature (Tg) of the polymer, marking the transition from a fluid to a glassy state. To replicate this methodology, it is important that the Tg of PSar-PBLG is high enough to freeze the different morphologies by water addition. The Tg

• the thermogram unveiled a peak during the initial heating cycle, spanning from 40 °C to 90 °C (Supporting Information File 1, Figure S18). This peak corresponds with the dehydration temperature of polysarcosine, suggesting its role in facilitating subsequent shape manipulation [16]. The assembly of

Facile one-pot reduction of β-nitrostyrenes to phenethylamines using sodium borohydride and copper(II) chloride

• Laura D’Andrea and
• Simon Jademyr

Beilstein J. Org. Chem. 2025, 21, 39–46, doi:10.3762/bjoc.21.4

• structures both prior to and following the production of the target compounds. The application of mild heating is crucial to reach full conversion of the starting materials in the times indicated in Table 1. However, conversion to the desired products is also achievable at room temperature over 18 hour

• stirring with minor yield loss. Increasing the heating temperature up to 110 °C does not lead to increased product yields (for more information on the optimization process, see Supporting Information File 1, page S19). The use of diethylenetriamine (DETA) was also investigated to evaluate its impact on the

• CuCl2 2 M solution were added dropwise but rapidly to the vessel. The reaction was monitored by TLC and refluxed at 80 °C in either oil bath or heating mantle for the time indicated in Table 1. General workup procedure of the amino products (1b–8b): Once cooled to room temperature, a 35% solution of

Emerging trends in the optimization of organic synthesis through high-throughput tools and machine learning

• Pablo Quijano Velasco,
• Kedar Hippalgaonkar and
• Balamurugan Ramalingam

Beilstein J. Org. Chem. 2025, 21, 10–38, doi:10.3762/bjoc.21.3

• adoption of HTE under batch conditions for optimizing chemical synthesis. However, several challenges arise when MTP are used as reaction vessels. First, the independent control of variables such as reaction time, temperature, and pressure within individual wells is not possible due to the inherent design

• constraints of parallel reactors that share the same MTP. In addition, challenges arise when standard MTP-based reaction vessels are used at a temperature near the solvent's boiling point, as this labware is not enclosed or able to cool the top of the reaction vessel to facilitate reflux conditions. Although

• some research groups have developed custom tools to enable high-temperature reactions, these reactors are currently not commercially available. For an in-depth discussion on the limitations of batch reactors for HTE, we refer the readers to a review by Taylor et al. on chemical reaction optimization [5

Synthesis, structure and π-expansion of tris(4,5-dehydro-2,3:6,7-dibenzotropone)

• Yongming Xiong,
• Xue Lin Ma,
• Shilong Su and
• Qian Miao

Beilstein J. Org. Chem. 2025, 21, 1–7, doi:10.3762/bjoc.21.1

• room temperature yielded partially fused nanographene 3 (20%), with formation of six C–C bonds giving four six-membered rings and two five-membered rings. Performing this reaction at a higher temperature led to a lower yield of compound 3 and the formation of byproducts with lower Rf values on thin

• , such as increasing the amount of DDQ or elevating the reaction temperature in the Scholl reaction of 10, only resulted in complex mixtures. Further attempts to subject 3 to the Scholl reaction conditions did not yield further cyclized products but led to the decomposition of the starting material

Synthesis, characterization, and photophysical properties of novel 9‑phenyl-9-phosphafluorene oxide derivatives

• Shuxian Qiu,
• Duan Dong,
• Jiahui Li,
• Huiting Wen,
• Jinpeng Li,
• Yu Yang,
• Shengxian Zhai and
• Xingyuan Gao

Beilstein J. Org. Chem. 2024, 20, 3299–3305, doi:10.3762/bjoc.20.274

• fully elucidated by single-crystal X-ray crystallography, which was performed on a Bruker APEX-II CCD diffractometer using graphite monochromated Mo Kα radiation at a temperature of 296 ± 2 K. Crystallographic data were deposited with the Cambridge Crystallographic Data Centre under accession number

• were conducted. UV−vis absorption spectra of 7 in toluene solution at room temperature are shown in Figure 2, and the corresponding data are included in Table 2. The spectra in Figure 2a exhibit two major absorption bands at ≈290 nm and ≈340 nm. The band at around 290 nm might be induced by π→π

• has insignificant effect on the molecular ground state of 7-H. The PL spectra of the PhFlOP-based compounds 7 in toluene at room temperature are shown in Figure 3, and the λem values are included in Table 2. Different emission wavelengths are observed due to the various substituents present in the

Reactivity of hypervalent iodine(III) reagents bearing a benzylamine with sulfenate salts

• Beatriz Dedeiras,
• Catarina S. Caldeira,
• José C. Cunha,
• Clara S. B. Gomes and
• M. Manuel B. Marques

Beilstein J. Org. Chem. 2024, 20, 3281–3289, doi:10.3762/bjoc.20.272

• conducted at room temperature for 20 hours, which resulted in a reduction of the yield for 5aa to 9% (Table 1, entry 5). This result might be due to the reactivity of this hypervalent iodine reagent. Indeed, we have previously observed that the transfer of the benzylamine moiety to carbon-based nucleophiles

• – room temperature. Scope of the primary amine electrophilic reaction of sulfenate salts. Reaction conditions: 4 (2 equiv), NaH (2.4 equiv), 2, degassed DMF (0.055 M). Isolated yields. rt – room temperature; NO – not observed. Electrophilic amination reaction in the presence of TEMPO. Reaction conditions

Efficient synthesis of fluorinated triphenylenes with enhanced arene–perfluoroarene interactions in columnar mesophases

• Yang Chen,
• Jiao He,
• Hang Lin,
• Hai-Feng Wang,
• Ping Hu,
• Bi-Qin Wang,
• Ke-Qing Zhao and
• Bertrand Donnio

Beilstein J. Org. Chem. 2024, 20, 3263–3273, doi:10.3762/bjoc.20.270

• substitution of the terminal phenyl ring with a pentafluorophenyl ring. Thus, as expected, they display a Colhex mesophase over large temperature ranges, with only small differences in the mesophase stability and transition temperatures. Furthermore, the presence of the terminal fluorophenyl group enables a

• , C10F8 (6F-BTPn), on the other. With only four alkoxy chains, these polar “Janus” mesogens [33][44] display a columnar hexagonal mesophase over broader temperature ranges and higher mesophase stability than the archetypical 2,3,6,7,10,11-hexa(alkoxy)triphenylene counterparts [48], whereas the

• compounds, Gnm, exhibit a rectangular columnar phase (Colrec) also over large temperature ranges from ambient up to 183 and 164 °C, respectively. The unsymmetrically alkoxy-substituted derivative, G48, also displays a Colrec over a similar temperature range. The compounds’ photophysical properties have also

Intramolecular C–H arylation of pyridine derivatives with a palladium catalyst for the synthesis of multiply fused heteroaromatic compounds

• Yuki Nakanishi,
• Shoichi Sugita,
• Kentaro Okano and
• Atsunori Mori

Beilstein J. Org. Chem. 2024, 20, 3256–3262, doi:10.3762/bjoc.20.269

• bromide in N,N-dimethylacetamide (DMA). Table 1 summarizes the results. The yield of the reaction improved as the temperature was increased from 90 °C to 130 °C (Table 1, entries 1–3). When the reaction was carried out at 150 °C, the yield decreased to 27%. A longer reaction period of 72 h at 130 °C also

• ), tetrabutylammonium bromide (31.7 mg, 0.098 mmol), Pd(OAc)2 (2.2 mg, 10 mol %), and triphenylphosphine (2.8 mg, 10 mol %). The mixture was dissolved in 3.1 mL of DMA and stirring was continued at 110 °C for 24 h. Then, water (3 mL) was added after cooling to room temperature. The product was extracted with

Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

• Sergio Torres-Oya and
• Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

• -catalyzed asymmetric inverse electron demand aza-Diels–Alder reaction of 1,3-diazadienes 21 and 3-vinylindoles 61 [47]. After a screening of reaction conditions, chiral phosphoric acid XIV was found to be the best organocatalyst, and by using dichloromethane as solvent at room temperature, 43 different

Discovery of ianthelliformisamines D–G from the sponge Suberea ianthelliformis and the total synthesis of ianthelliformisamine D

• Sasha Hayes,
• Yaoying Lu,
• Bernd H. A. Rehm and
• Rohan A. Davis

Beilstein J. Org. Chem. 2024, 20, 3205–3214, doi:10.3762/bjoc.20.266

• ; Pseudomonas; Suberea; total synthesis; Introduction The marine environment covers over two thirds of the earth’s surface and it encompasses a wide range of complex ecosystems that are highly variable in their physical attributes including pressure, salinity, temperature, and light availability. Both flora

• /CH2Cl2 at room temperature (17% yield). Subjecting the methoxylated benzaldehyde intermediate 9 to a Doebner–Knoevenagel condensation with malonic acid and pyridine afforded the brominated cinnamic acid analogue 10 in 54% yield [19]. Amidation chemistry using carbonyldiimidazole (CDI) [18] and the

• ground using a Fritsch Universal Cutting Mill Pulverisette 19. The ground marine sponge was extracted at room temperature using an Edwards Instrument Company Bioline orbital shaker set to 200 rpm. Solvents were removed from extracts with a Büchi R-144 rotary evaporator and from HPLC fractions using a

Synthesis of 2H-azirine-2,2-dicarboxylic acids and their derivatives

• Anastasiya V. Agafonova,
• Mikhail S. Novikov and
• Alexander F. Khlebnikov

Beilstein J. Org. Chem. 2024, 20, 3191–3197, doi:10.3762/bjoc.20.264

• not isomerize at room temperature, which is typical for highly sterically congested isoxazoles containing a 3-tert-butyl substituent [26]. The mechanism of such isomerizations of isoxazoles has been previously discussed using DFT calculations [25][26], which revealed the formation of an isoxazole–Fe

• complex, which facilitates the cleavage of the N–O bond and subsequent 1,3-cyclization, ultimately leading to the formation of 2H-azirine. Therefore, the isomerization of isoxazole 1j was carried out at a higher temperature, 82 °C, but after hydrolysis of the reaction mixture, instead of the expected

• azirine dicarboxylic acid 6j, oxazole-4-carboxylic acid 9 was isolated. Apparently, azirine 2j underwent ring opening at higher temperature to nitrile ylide 7, which after cyclization and hydrolysis gave acid 9 (Scheme 3) (cf., e.g. [23]). Next, given that the preparation of 2H-azirine-2-carboxamides from

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

• studies using methyl ester sulfoxonium ylide 1a and 2,2,2-trifuoroethyl(mesityl)iodonium triflate salt (2a), as model substrates (see also Table S1 in Supporting Information File 1). Combining these at room temperature in acetonitrile produced 3a in 8% 1H NMR yield (Table 1, entry 1). Repeating the

• was also not effective (Table 1, entry 7; 56% yield), extending the reaction time to 24 hours at room temperature gave 3a in 69% yield (Table 1, entry 8). Other chlorinated, ethereal or polar solvents were also tested under this prolonged reaction time, but none proved better than acetonitrile (Table

•  1, entries 9–12). We attempted to decrease the reaction time by increasing the temperature, but these changes resulted in decreased yields of 3a (Table 1, entries 13 and 14). Surprisingly, when using microwave (MW) heating at 70 ⁰C for 10 min in ACN, product 3a was formed in 74% yield (Table 1