Recent advances in Norrish–Yang cyclization and dicarbonyl photoredox reactions for natural product synthesis

• Peng-Xi Luo,
• Jin-Xuan Yang,
• Shao-Min Fu and
• Bo Liu

Beilstein J. Org. Chem. 2025, 21, 2315–2333, doi:10.3762/bjoc.21.177

• conformation of the substrates, thereby modulating their reactivities. Density functional theory calculations show that 22 prefers to proceed its annulation through TS22b (ΔΔG‡ = 0) to afford 23 rather than that via TS22a (ΔΔG‡ = 1.5 kcal/mol). In contrast, annulation of 30 undergoes through the low barrier

A chiral LC–MS strategy for stereochemical assignment of natural products sharing a 3-methylpent-4-en-2-ol moiety in their terminal structures

• Rei Suo,
• Raku Irie,
• Hinako Nakayama,
• Yuta Ishimaru,
• Yuya Akama,
• Masato Oikawa and
• Shiro Itoi

Beilstein J. Org. Chem. 2025, 21, 2243–2249, doi:10.3762/bjoc.21.171

• analysis, and computational methods have been widely used. For example, the absolute configuration of chaetomugilin B [19] was determined by X-ray crystallography, while that of capsulactone (1) was established through density functional theory (DFT)-based simulations of NMR chemical shifts and electronic

Electrochemical cyclization of alkynes to construct five-membered nitrogen-heterocyclic rings

• Lifen Peng,
• Ting Wang,
• Zhiwen Yuan,
• Bin Li,
• Zilong Tang,
• Xirong Liu,
• Hui Li,
• Guofang Jiang,
• Chunling Zeng,
• Henry N. C. Wong and
• Xiao-Shui Peng

Beilstein J. Org. Chem. 2025, 21, 2173–2201, doi:10.3762/bjoc.21.166

• mixture of propargyl alcohol 50 (0.7 mmol), NaN3 (2.8 mmol), n-Bu4NI (0.5 mmol) and MeCN (10 mL) under electrolysis (graphite rod as anode, stainless-steel plate as cathode, 11 mA) at rt for 10 h. According to the experimental results and density functional theory (DFT) calculations, a plausible mechanism

Understanding the origin of stereoselectivity in the photochemical denitrogenation of 2,3-diazabicyclo[2.2.1]heptene and its derivatives with non-adiabatic molecular dynamics

• Leticia A. Gomes and
• Steven A. Lopez

Beilstein J. Org. Chem. 2025, 21, 2007–2020, doi:10.3762/bjoc.21.156

• time-dependent density functional theory by computing the vertical excitation energy, oscillator strength, and nature of the electronic transition of 1, 3, and 5 with ωB97X-D [89]/aug-cc-pVTZ [90], SA(4)-CASSCF(8,9)/ANO-VDZP, and SA(4)-XMS-CASPT2 [91] (8,9)/ANO-S-VDZP levels of theory, as shown in

• couplings at each 0.5 fs timestep. Our results indicate that the retained stereochemistry of housane is generated in the ground state via thermal conversion from inverted housane/diradical. Computational Details Single reference methods We used density functional theory (DFT) to optimize the ground-state

• global minima of 1, 3, and 5. The molecular geometries were optimized using B3LYP/6-31(G) [102][103]. Time-dependent density functional theory (TD-DFT) was used to calculate the vertical excitation energies, wavelengths, and oscillator strength for the first 10 excited singlet states of 1, 3, and 5. The

Photochemical reduction of acylimidazolium salts

• Michael Jakob,
• Nick Bechler,
• Hassan Abdelwahab,
• Fabian Weber,
• Janos Wasternack,
• Leonardo Kleebauer,
• Jan P. Götze and
• Matthew N. Hopkinson

Beilstein J. Org. Chem. 2025, 21, 1973–1983, doi:10.3762/bjoc.21.153

• density functional theory (DFT) calculations were obtained. Results and Discussion Photoreduction of 2-benzoylimidazolium triflate with diisopropylethylamine Initial investigations To investigate the potential for the light-mediated reduction of acylazolium salts, compound 1 was prepared as a

• , however, did not reveal any significant change in the absorption profile. To gain further insight, time-dependent density functional theory (TD-DFT) calculations were carried out (for details of the computational studies, see Supporting Information File 1). In line with the UV–vis studies, comparison of

Thermodynamics and polarity-driven properties of fluorinated cyclopropanes

• Matheus P. Freitas

Beilstein J. Org. Chem. 2025, 21, 1742–1747, doi:10.3762/bjoc.21.137

• development of liquid crystals, ion carriers, and other technologies dependent on precise molecular properties. Computational Details The fluorinated cyclopropanes shown in Figure 1 were optimized using density functional theory (DFT) at the B3LYP-GD3BJ/6-311++G(d,p) level [20][21][22], which includes

Synthesis of optically active folded cyclic dimers and trimers

• Ena Kumamoto,
• Kana Ogawa,
• Kazunori Okamoto and
• Yasuhiro Morisaki

Beilstein J. Org. Chem. 2025, 21, 1603–1612, doi:10.3762/bjoc.21.124

• spectra were simulated by time-dependent density functional theory (TD-DFT) calculations (TD-MN15/6-31G(d)//MN15/6-31G(d). The calculated rotatory strengths of (Sp)-6 and (Sp)-7 were plotted with their observed CD spectra in Figure 3A and 3B, respectively, and the calculated CD spectra are shown in

Thermodynamic equilibrium between locally excited and charge transfer states in perylene–phenothiazine dyads

• Issei Fukunaga,
• Shunsuke Kobashi,
• Yuki Nagai,
• Hiroki Horita,
• Hiromitsu Maeda and
• Yoichi Kobayashi

Beilstein J. Org. Chem. 2025, 21, 1577–1586, doi:10.3762/bjoc.21.121

• synthesized and characterized (Figure 1). Their photophysical properties were comprehensively examined by steady-state and time-resolved emission and absorption spectroscopy. Furthermore, time-dependent density functional theory (TD-DFT) calculations were performed to support the experimental findings

• shown in Supporting Information File 1. Energy levels and steady-state optical properties Time-dependent density functional theory (TD-DFT) calculations were performed to gain insights into the electronic structures of Pe–PTZ derivatives at B3LYP/6-31+G(d,p) level of theory (Figure 2) [18]. The

pH-Controlled isomerization kinetics of ortho-disubstituted benzamidines: E/Z isomerism and axial chirality

• Ryota Kimura,
• Satoshi Ichikawa and
• Akira Katsuyama

Beilstein J. Org. Chem. 2025, 21, 1568–1576, doi:10.3762/bjoc.21.120

• hypothesis that the rotational barrier of the benzamidine changes upon protonation, density functional theory (DFT) calculations were performed for the C–N and C–N/C–C rotations of the molecular form and of the protonated 2-bromo-N,N,6-trimethylbenzimidamide as a model compound (Figure 2). Several transition

Azobenzene protonation as a tool for temperature sensing

• Antti Siiskonen,
• Sami Vesamäki and
• Arri Priimagi

Beilstein J. Org. Chem. 2025, 21, 1528–1534, doi:10.3762/bjoc.21.115

• -dichloroethane and highlight its potential for temperature sensing applications. Density functional theory calculations were performed to support our findings and to investigate the mechanisms of azobenzene–acid interactions, aiming to guide the design of azobenzene-based temperature sensors in future research

• molecule substantially enhances protonation, lowering ∆G° from −1.59 to −5.81 kcal/mol. Spectral changes upon protonation were also studied computationally using time-dependent density functional theory (TDDFT). Analysis of the molecular orbitals involved in the electronic transitions confirms that the

Wittig reaction of cyclobisbiphenylenecarbonyl

• Taito Moribe,
• Junichiro Hirano,
• Hideaki Takano,
• Hiroshi Shinokubo and
• Norihito Fukui

Beilstein J. Org. Chem. 2025, 21, 1454–1461, doi:10.3762/bjoc.21.107

• nucleophilic substitution of the thus generated alkoxide to form an oxygen-containing five-membered ring. At least, density functional theory (DFT) calculations support that the nucleophilic attack of methylenetriphenylphosphorane to the exo-methylene unit is slightly favorable over reaction with the carbonyl

High-pressure activation for the solvent- and catalyst-free syntheses of heterocycles, pharmaceuticals and esters

• Kelsey Plasse,
• Valerie Wright,
• Guoshu Xie,
• R. Bernadett Vlocskó,
• Alexander Lazarev and
• Béla Török

Beilstein J. Org. Chem. 2025, 21, 1374–1387, doi:10.3762/bjoc.21.102

• using density functional theory (DFT) with the Becke three-parameter exchange and Lee–Yang–Parr correlation (B3LYP) functional [49], along with the 6–311++G(d,p) basis set for gas-phase calculations of all compounds. After completing the molecular geometry optimizations, vibrational frequency

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

• Bartłomiej Pigulski

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

• reported by Feng and co-workers (Scheme 24) [110]. Precursor 181 was annealed on an Au(111) surface at 300 °C, resulting in PAH 182 with two embedded azulene subunits. Spin-polarized density functional theory calculations predicted that PAH 182 would exhibit an open-shell singlet ground state, as it

• of the diverse range of azulene-embedded nanographenes discussed in this review presents a significant challenge, as many of the original studies lack comprehensive data. In numerous cases, fluorescence characteristics were not thoroughly examined, and time-dependent density functional theory (TD-DFT

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

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

• chromatography with 30:70 EtOAc/hexanes. Product structures were confirmed by 1H and 13C NMR analysis and X-ray crystal structure analysis of 8a. Density functional theory (DFT) calculations DFT computations were conducted utilizing Gaussian 16W with the B3LYP functional and the 6-31G(d,p) basis set [21][22

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

• intensity borrowing from higher excited states, due to orbital overlap, does not explain the improved performance sufficiently, especially when comparing the oscillator strengths that can be determined using density functional theory (DFT) studies [19][20][21]. Moreover, when looking at di- or multiradicals

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

• experimentally in the solvatochromism study of fluorescence using solvents with diverse polarities (see Supporting Information File 1, Figure S9). Indeed, the density functional theory (DFT) calculation performed at WB97XD/Def2TZVP level of theory showed the lowest value for the HOMO–LUMO energy gap in compound

Substituent effects in N-acetylated phenylazopyrazole photoswitches

• Radek Tovtik,
• Dennis Marzin,
• Pia Weigel,
• Stefano Crespi and
• Nadja A. Simeth

Beilstein J. Org. Chem. 2025, 21, 830–838, doi:10.3762/bjoc.21.66

• often show higher quantum yields and increased thermal half-life of the metastable state. For the half-life, the choice of the heterocycle is crucial, as revealed through density functional theory (DFT) calculations, which showed that a 5-membered ring promotes the stability of the Z isomer [30]. Within

4-(1-Methylamino)ethylidene-1,5-disubstituted pyrrolidine-2,3-diones: synthesis, anti-inflammatory effect and in silico approaches

• Nguyen Tran Nguyen,
• Vo Viet Dai,
• Luc Van Meervelt,
• Do Thi Thao and
• Nguyen Minh Thong

Beilstein J. Org. Chem. 2025, 21, 817–829, doi:10.3762/bjoc.21.65

• , while density functional theory (DFT) calculations provided insights into their electronic properties, including reactivity and stability. This comprehensive approach, integrating synthesis, biological evaluation, and computational methods, highlights the potential of 4-(1-methylamino)ethylidene-1,5

• compounds and the reference drug dexamethasone (DEX) against the iNOS enzyme. The interactions between the ligands and the target enzyme were further visualized and analyzed using Discovery Studio software [47]. Density functional theory (DFT) method: The molecular structures of the tested compounds were

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

• , computational density functional theory calculations were performed focusing on the oxidative addition transition states (S,R)-TS8 and (S,S)-TS9 (Scheme 19b). The theoretical analysis revealed a notable energy difference between these diastereomeric transition states, with (S,R)-TS8 being 4.11 kcal/mol lower in

Unraveling aromaticity: the dual worlds of pyrazole, pyrazoline, and 3D carborane

• Zahra Noori,
• Miquel Solà,
• Clara Viñas,
• Francesc Teixidor and
• Jordi Poater

Beilstein J. Org. Chem. 2025, 21, 412–420, doi:10.3762/bjoc.21.29

• of aromaticity. Therefore, relying solely on NICS can be misleading, and other computational indicators, along with experimental or structural data, should be used to accurately assess aromaticity. Keywords: 3D aromaticity; carborane; density functional theory; NICS ambiguity; pyrazole

• calculations were performed with the Gaussian 16 package [64] by means of the B3LYP [65][66][67] hybrid density functional and the 6-311++G(d,p) basis set [68]. The geometry optimizations were carried out without symmetry constraints (Table S2 in Supporting Information File 1). Analytical Hessians were

The effect of neighbouring group participation and possible long range remote group participation in O-glycosylation

• Rituparna Das and
• Balaram Mukhopadhyay

Beilstein J. Org. Chem. 2025, 21, 369–406, doi:10.3762/bjoc.21.27

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

• simulated using Spartan’10 [26] on the PM6 level of theory [27]. Density-functional theory (DFT) calculations were computed utilizing the Gaussian program package, revision C.01 [28]. The geometry of the conformers was optimized on the B3LYP/6-311+G(2d,p) [29][30][31][32] level of theory with tight cutoffs

Synthesis and characterizations of highly luminescent 5-isopropoxybenzo[rst]pentaphene

• Islam S. Marae,
• Jingyun Tan,
• Rengo Yoshioka,
• Zakaria Ziadi,
• Eugene Khaskin,
• Serhii Vasylevskyi,
• Ryota Kabe,
• Xiushang Xu and
• Akimitsu Narita

Beilstein J. Org. Chem. 2025, 21, 270–276, doi:10.3762/bjoc.21.19

• optimized by density functional theory (DFT) calculations (Figure S2 in Supporting Information File 1). The optoelectronic properties of BPP-OiPr 3 and BPP-dione 4 were initially investigated by UV–vis absorption spectroscopy in comparison with BPP 2 (Figure 2a). BPP 2 and BPP-OiPr 3 displayed similar and

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

• analysis of the thermal back reaction revealed activation parameters, highlighting how the substitution position of the aryl group affects the thermal stability. Additionally, density functional theory calculations identified M06 and MPW1PW91 as the most accurate functionals for predicting the thermal back

• effective methods for predicting the thermal back reactivity, density functional theory (DFT) calculations can be considered [51][58][59][60][61][62]. For example, in previous studies on the thermal back reactivity of diarylbenzene that is an analogue of diarylethene, we found that the M06-2X level of