Kinetic resolution of racemic planar-chiral vinylcymantrenes by molybdenum-catalyzed asymmetric metathesis dimerization

• Haruna Imazu,
• Hitoshi Izu,
• Yasuhiro Ohki and
• Masamichi Ogasawara

Beilstein J. Org. Chem. 2026, 22, 568–574, doi:10.3762/bjoc.22.42

• benzene at the indicated temperature in the presence of an appropriate chiral Mo-precatalyst (10 mol %), which was generated in situ from the Mo-precursor, (pyrrolyl)2Mo(=CHCMe2Ph)(=N-C6H3-2,6-iPr2) [36], and an axially chiral biphenol ligand. The chiral Mo/(R)-L1 precatalyst [21] facilitated the

• , entry 5). On the other hand, the effects of lowering the temperature were minimal in the reactions using Mo/(R)-L3 (Table 1, entries 6 and 7). The optimized conditions as in entries 4 and 6 were applied to the AMD/KR reactions of rac-1b and 1c as well. The AMD/KR of rac-1b using Mo/(R)-L1 proceeded with

Experimental and DFT studies on the regioselective methanolysis of 5-azido-9-oxabicyclo[6.1.0]nonan-4-yl 4-nitrobenzoate isomers

• İlknur Polat,
• Selçuk Eşsiz and
• Emine Salamci

Beilstein J. Org. Chem. 2026, 22, 547–556, doi:10.3762/bjoc.22.40

• -(dimethylamino)pyridine (DMAP, 2 mg) were added and the mixture was stirred at room temperature for 24 hours. Then, the solution was cooled to 0 °C and 100 mL of 2 M HCl added and stirred for 5 min. The mixture was extracted with ethyl acetate (4 × 30 mL). The organic phase was washed with saturated NaHCO3 (2

• 0 °C. m-CPBA (77%, 0.73 g, 3.26 mmol) and NaHCO3 (0.282 g, 3.36 mmol) were added and the mixture was stirred at room temperature for 36 hours. Then, the solution was cooled to 0 °C and 100 mL of 3 M NaOH added, and stirring continued for 40 min. The mixture was extracted with CH2Cl2 (4 × 30 mL). The

• at room temperature to obtain colourless crystals, mp: 101–102 °C. Compound 11 was recrystallized from the same solvent mixture at 0 °C and obtained as slightly yellow crystals, mp: 117–119 °C. (1S*,2S*,5S*,6S*)-6-Acetoxy-2-azido-5-chlorocyclooctyl 4-nitrobenzoate (10): 1H NMR (400 MHz, CDCl3) δ 8.34

Melifoliox B, a novel phloroglucin derivative isolated from Melicope barbigera (Rutaceae) and synthesis of new oxidation products from melifoliones A and B

• Horst Weber,
• Kim-Thao Tran-Cong,
• Bernhard Mayer,
• Guido J. Reiss,
• Iryna S. Konovalova,
• Marc S. Appelhans,
• Kenneth R. Wood and
• Claus M. Passreiter

Beilstein J. Org. Chem. 2026, 22, 535–546, doi:10.3762/bjoc.22.39

• -toluenesulfonic acid at 80 °C in toluene afforded benzoxocin (7) as the only product. On the other hand, melifolione A (1) was completely decomposed under these conditions. Irradiation of 5 in methanol with UV-light (300 nm) for 3 days at room temperature gave melifolione B (2) with traces of melifolione A (1

• reagents were of analytical grade. Melting points were determined on a Büchi SMP 20. Microwave experiments were performed in sealed tubes on a CEM, model DISCOVER, power 300 Watt apparatus with a special temperature programme. Isolation of compound 4 Compound 4 was isolated from the VLC-fraction MB-IX-5-P1

• -trihydroxyacetophenone (3.7 g, 20 mmol), citral (3.2 g, 21 mmol) and pyridine (1.6 g, 20 mmol) was heated with stirring in a water bath at max. 60 °C for 8 h. After cooling to room temperature, the reaction mixture was diluted with 200 mL diethyl ether and extracted with 0.1 N H2SO4 (3 × 20 mL) to remove the pyridine

Get a better glimpse on sequential photoreactions of trisnorbornadienes with ¹⁹F NMR spectroscopy

• Julian Felix Maria Hebborn,
• Ben Eric Merten,
• Thomas Paululat and
• Heiko Ihmels

Beilstein J. Org. Chem. 2026, 22, 527–534, doi:10.3762/bjoc.22.38

• mass, indicating decomposition above this temperature (see Supporting Information File 1, Figure S3). The cycloreversion of trisquadricyclane 2f0,3 was also initiated in a ground-state reaction with magic blue (5), which has already been shown to be an effective catalyst for this reaction [46][47][48

• be considered an improved property, the energy density of this compound is lower than that of the parent compound 2b because of the higher molecular mass. The experimental results showed a decomposition of trisquadricyclane 2f0,3 at higher temperature, which is accompanied by significant loss of mass

• ]heptadien-2-yl)-1,3,2-dioxaborolane (1e, 501 mg, 2.30 mmol), Pd(PPh3)4 (66.5 mg, 57.5 µmol, 5 mol %), THF (5.0 mL), and aq. NaOH (5.7 mmol, 2.7 M, 2.1 mL) was stirred at 80 °C for 16 h under anaerobic conditions [22]. After cooling the emulsion to room temperature, EtOAc (15 mL) was added and the organic

Modern synthetic pathways towards eribulin and its subunits

• Sebastian Dominik Graf

Beilstein J. Org. Chem. 2026, 22, 495–526, doi:10.3762/bjoc.22.37

• products were fused together by the nucleophilic attack of deprotonated alkyne 265 to aldehyde 261 (Scheme 31). The obtained diastereomers 266 were oxidized to the respective ketone 267, and again, Noyori reduction was performed to access 268 [105]. Treatment with AgBF4 at elevated temperature induced a

Synthesis and uranyl(VI) extraction performance of a calix[4]pyrrole–tetrahydroxamic acid receptor

• Sara Karnib,
• Rana Baydoun,
• Wissam Zaidan,
• Nancy AlHaddad,
• Omar El Samad,
• Bilal Nsouli,
• Francine Cazier-Dennin and
• Pierre-Edouard Danjou

Beilstein J. Org. Chem. 2026, 22, 486–494, doi:10.3762/bjoc.22.36

• calixarene tetraethylacetate [53]. In the original procedure, KOH was added at −5 °C, and the mixture was stirred for 5 hours at this temperature, followed by 5 days of stirring at room temperature. In our hands, both the addition of KOH and stirring were performed entirely at room temperature, and 1H NMR

• experiments, parameters like temperature, shaking time and volume of uranyl solution used were kept constant. In a typical experiment, 20 mL of a 1 mM aqueous uranyl acetate solution was adjusted to the target pH and then added to solid PCP HA. The solution was shaken at a fixed temperature of 25 °C for 4 h

Structural reassignment of compound 968, an allosteric glutaminase inhibitor

• Lindsey A. Albertelli,
• Sainabou Jallow,
• Chun Li and
• Scott M. Ulrich

Beilstein J. Org. Chem. 2026, 22, 455–460, doi:10.3762/bjoc.22.33

• -dimethylaminobenzaldehyde 4-Dimethylaminobenzaldehyde (4.02 g, 26.9 mmol) was dissolved in 1,4-dioxane (52 mL) and NBS (5.01 g, 28.2 mmol) was added in small portions with stirring over 5 minutes. The reaction mixture was stirred at room temperature for 20 minutes then poured into 50 mL water. The mixture was diluted with

• × 0.124 × 0.064 mm3) and quality was selected from a representative sample of crystals of the same habit using an optical microscope, mounted onto a Mitegen MicroLoopsTM (MiTeGen, LLC., Ithaca, NY) and placed in a cold nitrogen stream of nitrogen. Low temperature (100 K) X-ray data were obtained on a

• solution of the test compound in DMSO or DMSO itself was added (1 µL), mixed by gently pipetting up and down, then incubated for seven minutes at room temperature. The glutaminase reaction was initiated by addition of 20 µL of a solution of glutamine (100 mM) and K2HPO4 (500 mM), then mixed by gently

A facile and practical method for the synthesis of trans-(±)-taxifolin and its derivatives via Darzens reaction

• Bo Peng,
• Panpan Yang,
• Maaz Khan,
• Xiaotong Lin,
• Jiang Wu,
• Peng Fu and
• Qingqing Wu

Beilstein J. Org. Chem. 2026, 22, 443–450, doi:10.3762/bjoc.22.31

• give protected acetophenone 1 in an excellent yield of 78%. Next, the reaction conditions for the following α-bromination of acetophenone 1 to intermediate 2 were screened (Table S1, Supporting Information File 1). The treatment of compound 1 with CuBr2 in EtOAc at either room temperature or 60 °C

• all the Lewis acids screened, ZnCl2 was associated with best yield of 90%. Overall, the optimal conditions for the Darzens reaction involved treatment of 2 (1.0 equiv) with 3a (1.2 equiv) in MeCN at room temperature, using t-BuOLi (1.2 equiv) as the base and ZnCl2 (0.1 equiv) as Lewis acid catalyst

• mmol, 1.0 equiv), 3 (1.2 equiv), t-BuOLi (1.2 equiv) and ZnCl2 (10 mol %) in CH3CN (4.5 mL), stirred at room temperature for 4–6 h, N2 atmosphere. aZnCl2 was not added and the reaction time was 15 h. Yields are isolated yields. Synthesis of trans-(±)-taxifolin and its derivatives via the approach

Synthesis and stereochemical analysis of dynamic planar chiral oxa[7]orthocyclophene

• Yukiho Hashimoto,
• Yuuya Kawasaki,
• Kazunobu Igawa and
• Katsuhiko Tomooka

Beilstein J. Org. Chem. 2026, 22, 436–442, doi:10.3762/bjoc.22.30

• at ambient temperature. The phenyl-substituted oxacyclophene showed more pronounced dynamic planar chirality than the iodo- and methyl-substituted derivatives. The planar chirality of the oxacyclophene was successfully transformed into central chirality by epoxidation without loss of enantiomeric

Synthesis and anti-cancer activity of naphthalimide–organylselanyl conjugates

• Rajkumar Ravi and
• Selvakumar Karuthapandi

Beilstein J. Org. Chem. 2026, 22, 416–435, doi:10.3762/bjoc.22.29

• mmol) was added, and the reaction mixture was refluxed for 48 h. The reaction progress was monitored by TLC upon completion of the reaction. The mixture was allowed to cool to room temperature, and the solvent was removed under reduced pressure. The obtained residue was dissolved in chloroform and

• ethanol, and the reaction mixture was refluxed for 8 hours. The progress of the reaction was monitored by TLC. After completion, the reaction mixture was cooled to room temperature and the solvent was removed under reduced pressure. The resulting residue was dissolved in 30 mL of chloroform and washed

• completion, the reaction mixture was allowed to cool to room temperature, and the resulting precipitate was filtered, washed with ethanol, and dried to afford bromo compound 12 as an off-white powder (1.5 g, 66%). mp: 125 °C; 1H NMR (400 MHz, CDCl3) δ 8.64 (d, J = 7.2 Hz, 1H), 8.56 (d, J = 8.6 Hz, 1H), 8.39

Cone p-aminocalix[4]arenes enriched with ‘clickable’ alkyne or azide functionalities

• Ilia Korniltsev,
• Vasily Bazhenov,
• Alexander Gorbunov,
• Dmitry Cheshkov,
• Stanislav Bezzubov,
• Vladimir Kovalev and
• Ivan Vatsouro

Beilstein J. Org. Chem. 2026, 22, 399–415, doi:10.3762/bjoc.22.28

• (to ≈1 M), reducing the content of acetic acid in the mixture (to 1 mol per mol of HNO3) and extending the room-temperature reaction time to 72 h. Yet, under these conditions, the desired calix[4]arene 11 was obtained in only 31% yield (Scheme 2), and further variations in reagent excess/concentration

• , the room-temperature nitration of the silylated p-tert-butylcalix[4]arene ether 8 using 2.5 equiv of HNO3 per calixarene aromatic unit resulted in di- or trinitrated macrocycles 12 and 14 as the major products, when ≈0.2 and ≈1 M nitric acid concentrations were used. Similarly, the wide-rim

• -temperature preparation of the tetrapropargyl ether 24 from its silylated precursor 21. Surprisingly, attempts to apply these conditions to a complete removal of TBS groups in the less sterically hindered propargyl ethers 22 and 23 failed, and large amounts of the starting materials (as well as the partially

Dialkylaminoalkylation of β-ketosulfones via ring-opening of 3-sulfonylpyrrolidines

• Evgeny M. Buev,
• Alexander V. Pavlushin,
• Vladimir S. Moshkin and
• Vyacheslav Y. Sosnovskikh

Beilstein J. Org. Chem. 2026, 22, 383–389, doi:10.3762/bjoc.22.26

• decided to increase the reaction temperature. Thus, refluxing the reagents in the PhMe/MTBE mixture (v/v 17/3, approximately 100 °C) for 4 h led to complete conversion of the ketosulfone and formation of 3-phenylsulfonyl-3-benzoyl-N-methylpyrrolidine (2a) in almost quantitative yield. Despite that [3 + 2

• temperature resulted in the formation of a complex mixture with only traces of product 5. Nevertheless, the sequence of the nucleophilic ring-cleavage of the pyrrolidine ammonium salt 3 with alcohol, amine or thiol and the subsequent reduction with LiAlH4 serves as a formal reductive cleavage of the N–C2 bond

Electrosynthetic access to unsymmetrical oxaza[8]helicenes with high chiral stability and strong circularly polarized luminescence (CPL)

• Tin Zar Aye,
• Rubal Sharma,
• Muthu Karuppasamy,
• Daiya Suzuki,
• Haruka Nakajima,
• Yoshitane Imai,
• Mitsuhiro Arisawa,
• Mohamed S. H. Salem and
• Shinobu Takizawa

Beilstein J. Org. Chem. 2026, 22, 372–382, doi:10.3762/bjoc.22.25

• Supporting Information File 1), we developed a one-pot electrochemical annulation between 3 and β-naphthol derivative 4. Using n-Bu4NPF6 as the electrolyte in CH2Cl2 at room temperature, this protocol furnished oxaza[8]helicenes 5 in good-to-moderate yields with >75% Faradaic efficiency, and no homo-coupling

• mol−1, respectively (Figure 3C and 3D), which leads to rapid enantiomerization within a few hours at room temperature and severely limits their applicability in chiroptical devices despite their favorable CD and CPL properties (vide infra). By comparison, the markedly higher (P/M) enantiomerization

• enantiomers at lower temperature and samples were stored at −20 °C before their chiroptical responses were evaluated. The optical purities of (P/M)-6a and (P/M)-6b measured samples were confirmed to be >97% ee, confirming the reliability of our results. However, this low enantiomerization barriers of oxaza[7

Ring contraction and ring expansion reactions in terpenoid biosynthesis and their application to total synthesis

• Nicolas Kratena,
• Nicolas Heinzig and
• Peter Gärtner

Beilstein J. Org. Chem. 2026, 22, 289–343, doi:10.3762/bjoc.22.21

Arene activation via π-bond localization: concepts and opportunities

• Paul Meiners,
• Julian J. Melder and
• Tobias Morack

Beilstein J. Org. Chem. 2026, 22, 257–273, doi:10.3762/bjoc.22.19

• Taube reported the now famous pentaammineosmium(II) η2-benzene complex: the first system to yield kinetically stable η2-arene complexes that resist ligand exchange at room temperature in solution (Figure 5) [48]. This breakthrough opened the door to the isolation of such complexes and their subsequent

• early example was reported by Stille and co-worker in 1978, who elegantly demonstrated the formation of an η3-benzyl–palladium complex via oxidative addition of Pd(0) to a benzyl halide (Scheme 5C) [73]. Detailed stereochemical and NMR analyses revealed a temperature- and solvent-dependent equilibrium

A mild and atom-efficient four-component cascade strategy for the construction of biologically relevant 4-hydroxyquinolin-2(1H)-one derivatives

• Dmitrii A. Grishin,
• Kseniia I. Sharkovskaia,
• Ilya G. Kolmakov,
• Daria A. Ipatova,
• Rostislav A. Petrov,
• Nikolai D. Dagaev,
• Dmitry A. Skvortsov,
• Maria G. Khrenova,
• Valeriy V. Andreychev,
• Sergei A. Evteev,
• Yan A. Ivanenkov,
• Roman L. Antipin,
• Olga А. Dontsova and
• Elena K. Beloglazkina

Beilstein J. Org. Chem. 2026, 22, 244–256, doi:10.3762/bjoc.22.18

• a related protocol operating at room temperature using the ionic liquid [Bmim]HSO4 as a catalyst, expanding the scope to include aliphatic aldehydes [38]. Later, in 2017, Esmayeel Abbaspour-Gilandeh et al. reported a modified variant of this transformation under solvent-free heating, catalyzed by

• the presence of catalytic DMF in ethanol (Scheme 3a) [40]. A small amount of ethanol ensured homogeneity of the reaction mixture, allowed gradual temperature increase, and prevented sudden charring. DMF, with its high boiling point, acted as a homogenizer by preventing solidification after ethanol

• with α,β-unsaturated esters, such as (E)-3-(3,4-dimethoxyphenyl)acrylic acid esters 3 (see Supporting Information File 1) exemplified by compound 4. Different solvents and catalysts, both acidic and basic, were screened at room temperature, including refluxing in pyridine with piperidine, but the

Configuration–packing synergy enabling integrated crystalline-state RTP and amorphous-state TADF

• Ruiyan Wang and
• Yunan Wu

Beilstein J. Org. Chem. 2026, 22, 224–236, doi:10.3762/bjoc.22.16

• analysis indicate that the HOMO and LUMO are localized on the carbazole and phthalimide fragments, respectively, affording a small singlet–triplet energy gap. In the solid state, compound 1 exhibits pronounced phase dependence: powder samples display room-temperature delayed emission with principal bands

• at 550/600 nm and a lifetime of ≈0.39 s that undergoes strong thermal quenching, diagnostic of room-temperature phosphorescence. In contrast, amorphous films show no RTP; their delayed component grows with temperature and shares the same peak position as the prompt emission, consistent with thermally

• activated delayed fluorescence (TADF). Correlating temperature-dependent lifetimes with phase characterization indicate that, in amorphous environments lacking ordered π–π stacking and rigid confinement, the small ΔEST promotes reverse intersystem crossing, yielding delayed fluorescence; whereas in powder

Synthesis of diaryl phosphates using phytic acid as a phosphorus source

• Kazuya Asao,
• Seika Matsumoto,
• Haruka Mori,
• Riku Yoshimura,
• Takeshi Sasaki,
• Naoya Hirata,
• Yasuyuki Hayakawa and
• Shin-ichi Kawaguchi

Beilstein J. Org. Chem. 2026, 22, 213–223, doi:10.3762/bjoc.22.15

• esters could be slightly improved by using a catalytic amount of 1-butylimidazole; however, in the present work, a catalyst was not employed to simplify the purification step. The reaction temperature in this process should have been set to 230 °C. However, at this temperature, a burnt black material was

• obtained in the reaction mixture owing to the side reaction of the inositol moiety of phytic acid, which decreased the isolated yields of diaryl phosphates. Therefore, the reaction temperature was set to 200 °C, and the reaction time was extended to 48 h. Figure 3 shows the reaction conditions and aromatic

• S2 in Supporting Information File 1, phytic acid decomposed immediately after the oil bath temperature increased to 200 °C and released phosphoric acid into the reaction mixture. We assume that two types of phytic acid degradation occurred. One is a simple hydrolysis of the phosphate ester bond, and

Base-promoted deacylation of 2-acetyl-2,5-dihydrothiophenes and their oxygen-mediated hydroxylation

• Vladimir G. Ilkin,
• Margarita Likhacheva,
• Igor V. Trushkov,
• Tetyana V. Beryozkina,
• Vera S. Berseneva,
• Vladimir T. Abaev,
• Wim Dehaen and
• Vasiliy A. Bakulev

Beilstein J. Org. Chem. 2026, 22, 192–204, doi:10.3762/bjoc.22.13

• products (Scheme 1D) or the deacetylated products (Scheme 1E) have been developed. Results and Discussion Dihydrothiophene 1a was selected as a model substrate for our optimization study (Table 1). Initially, this compound was treated in ethanolic solution (2 mL) at room temperature in air for 1 h in the

Improved synthesis and physicochemical characterization of the selective serotonin 2A receptor agonist 25CN-NBOH

• Adrian G. Rossebø,
• Hannah G. Kolberg,
• Anders E. Tønder,
• Louise Kjaerulff,
• Poul Erik Hansen,
• Karla A. Frydenvang,
• Jesper Østergaard and
• Jesper L. Kristensen

Beilstein J. Org. Chem. 2026, 22, 175–184, doi:10.3762/bjoc.22.11

• stable in aqueous solutions at room temperature. Furthermore, we show that an intramolecular hydrogen bond is present in solution, which presumably is a key contributor to the high membrane permeability. Collectively, this physical-chemical profiling of 25CN-NBOH provides guidance to researchers with

• evaluation has not been conducted. The most widely used form of 1 is the corresponding HCl salt (1·HCl) that in our experience is a crystalline, nonhygroscopic and free-flowing solid, and aqueous solutions thereof appear stable for weeks at room temperature. To substantiate these qualitative observations, we

• for 1.5 hours at room temperature. Subsequently, the reaction was cooled in an ice bath before NaBH4 (192 mg, 5.08 mmol, 2.03 equiv) was added in four portions over 15 minutes. The reaction was left to stir at that temperature for an additional 20 minutes before leaving it at room temperature for 35

A new synthesis of Tyrian purple (6,6’-dibromoindigo) and its corresponding sulfonate salts

• Holly Helmers,
• Mark Horton,
• Julie Concepcion,
• Jeffrey Bjorklund and
• Nicholas C. Boaz

Beilstein J. Org. Chem. 2026, 22, 167–174, doi:10.3762/bjoc.22.10

• microcrystalline solid, was observed to be bench-stable for several months when stored in a sealed glass scintillation vial under ambient atmosphere at room temperature. Using the mild Kornblum oxidation, 4-bromo-2-nitrobenzyl bromide (6) was converted into the desired 4-bromo-2-nitrobenzaldehyde (4). As shown in

Circumventing Mukaiyama oxidation: selective S–O bond formation via sulfenamide–alcohol coupling

• Guoling Huang,
• Huarui Zhu,
• Shuting Zhou,
• Wanlin Zheng,
• Fangpeng Liang,
• Zhibo Zhao,
• Yifei Chen and
• Xunbo Lu

Beilstein J. Org. Chem. 2026, 22, 158–166, doi:10.3762/bjoc.22.9

• efficiency of the S(=N)–O bond formation. Under the standard conditions (Table 1, entries 1–10), 1a (0.15 mmol) was treated in MeOH (2a, 1.0 mL, ca. 24.6 mmol; ca. 160 equiv relative to 1a) at room temperature. To improve the compatibility of the protocol with solid or high molecular weight alcohols, we

• moiety. PIDA-mediated approach versus the present NBS-mediated approach to sulfinimidate esters. Substrate scope of sulfenamides derived from various thiophenols and thiols. Reaction conditions: sulfenamide 1 (0.15 mmol), NBS (1.2 equiv), NaHCO3 (1.5 equiv), MeOH (1.5 mL), room temperature, 30 min

• . Yields are of isolated products. Substrate scope of sulfenamides derived from various amides. Reaction conditions: sulfenamide 1 (0.15 mmol), NBS (1.2 equiv), NaHCO3 (1.5 equiv), MeOH (1.5 mL), room temperature, 30 min. Yields are of isolated products. Substrate scope of reactions between sulfenamides 1a

Asymmetric Mannich reaction of aromatic imines with malonates in the presence of multifunctional catalysts

• Kadri Kriis,
• Harry Martõnov,
• Annette Miller,
• Mia Peterson,
• Ivar Järving and
• Tõnis Kanger

Beilstein J. Org. Chem. 2026, 22, 151–157, doi:10.3762/bjoc.22.8

• conversion of the starting imine within 3 hours at rt and in 5 hours at −20 °C. Decrease of the temperature increases the enantiomeric purity of the product (from 27% ee up to 52% ee) (Table 1, entries 1–3). The corresponding H-analogue of catalyst A was less selective (18% ee) (Table 1, entries 4 and 5

• stirred at room temperature until a suspension was formed (ca 5 min). After that, the reaction mixture was cooled to −20 °C. The malonic ester (0.171 mmol, 3.0 equiv) was added to the reaction vessel via syringe. The reaction was stirred at −20 °C for an appropriate time. The progress of the reaction was

Design and synthesis of an axially chiral platinum(II) complex and its CPL properties in PMMA matrix

• Daiki Tauchi,
• Sota Ogura,
• Misa Sakura,
• Kazunori Tsubaki and
• Masashi Hasegawa

Beilstein J. Org. Chem. 2026, 22, 143–150, doi:10.3762/bjoc.22.7

• solutions (1.0 × 10−5 M) and 1 wt % PMMA matrices were acquired using a JASCO FP-8550 spectrometer at room temperature, at excitation wavelength of 300 nm (both solution and PMMA matrix). CPL spectra of CH2Cl2 solutions (1.0 × 10−5 M) and 1 wt % PMMA matrices were measured with a JASCO CPL-300

• spectrofluoropolarimeter at room temperature, at a scattering angle of 0° upon excitation with unpolarized, monochromated incident light. Absolute PLQYs of solutions and powder samples were determined using a JASCO FP-8550 spectrometer with an integrating sphere (JASCO ILF-533, diameter 96 mm) at an excitation wavelength

• (112 mg, 0.0962 mmol) and trimethylsilylacetylene (0.40 mL, 2.9 mmol) was added degassed solution of Et3N (2.6 mL, 19 mmol) and toluene (5.2 mL) by argon bubbling. The reaction mixture was refluxed at 90 °C for 21 hours. After cooling to room temperature, the reaction mixture was filtered through

Symmetrical D–π–A–π–D indanone dyes: a new design for nonlinear optics and cyanide detection

• Ergin Keleş,
• Alberto Barsella,
• Nurgül Seferoğlu,
• Zeynel Seferoğlu and
• Burcu Aydıner

Beilstein J. Org. Chem. 2026, 22, 131–142, doi:10.3762/bjoc.22.6

• have higher polarizability values and dipole moments (μ) than 2c. TGA analysis Thermogravimetric analyses (TGA) were performed to determine the thermal stability of the dyes. The TGA method allows the determination of thermal and gravimetric changes in the material following temperature increases. Dyes

• , especially those with potential for use in optical systems, must be stable up to certain temperatures depending on the systems [34][35][36]. The percentage mass loss versus temperature graph is shown in Figure 8. The decomposition temperatures (Td) of the dyes are given in Table 5. Results show that the dyes