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

• characterization of all molecules is presented. A detailed assignment of the most relevant Raman bands obtained after vibrational analysis from the theoretical Raman spectrum obtained for the neutral state of m-1 is included in Table S7 of Supporting Information File 1. The most significant Raman feature for the

Metal-free double azide addition to strained alkynes of an octadehydrodibenzo[12]annulene derivative with electron-withdrawing substituents

• Naoki Takeda,
• Shuichi Akasaka,
• Susumu Kawauchi and
• Tsuyoshi Michinobu

Beilstein J. Org. Chem. 2024, 20, 2234–2241, doi:10.3762/bjoc.20.191

• was taken into account by the polarizable continuum model using the integral equation formalism (IEFPCM) [25] for DFT calculations. The optimized molecular structures were verified by vibrational analysis; equilibrium structures did not have imaginary frequencies and transition-state structures had

Novel route to enhance the thermo-optical performance of bicyclic diene photoswitches for solar thermal batteries

• Akanksha Ashok Sangolkar,
• Rama Krishna Kadiyam and
• Ravinder Pawar

Beilstein J. Org. Chem. 2024, 20, 1053–1068, doi:10.3762/bjoc.20.93

• method analogous to the previous studies [33][36]. The obtained TSs were re-optimized with PBE/6-311++G** level utilizing the Gaussian16 and vibrational analysis was performed at the same level of theory. The TS was confirmed as a first-order saddle point by the presence of a single imaginary frequency

Development of fluorinated benzils and bisbenzils as room-temperature phosphorescent molecules

• Shigeyuki Yamada,
• Takuya Higashida,
• Yizhou Wang,
• Masato Morita,
• Takuya Hosokai,
• Kaveendra Maduwantha,
• Kaveenga Rasika Koswattage and
• Tsutomu Konno

Beilstein J. Org. Chem. 2020, 16, 1154–1162, doi:10.3762/bjoc.16.102

• geometries of 1a and 1c were optimized at the CAM-B3LYP/6-31+G(d) level of theory. The absence of any imaginary frequency in the vibrational analysis proved that the calculated structures are the minima. Figure 3 shows the calculated Mulliken charge distributions of fluorinated 1a and nonfluorinated 1c. The

p-Pyridinyl oxime carbamates: synthesis, DNA binding, DNA photocleaving activity and theoretical photodegradation studies

• Panagiotis S. Gritzapis,
• Panayiotis C. Varras,
• Nikolaos-Panagiotis Andreou,
• Katerina R. Katsani,
• Konstantinos Dafnopoulos,
• George Psomas,
• Zisis V. Peitsinis,
• Alexandros E. Koumbis and
• Konstantina C. Fylaktakidou

Beilstein J. Org. Chem. 2020, 16, 337–350, doi:10.3762/bjoc.16.33

• . From there, dissociation of the N–O bond starts to take place and proceeds uphill through a transition state, T1(TS), the structure of which was optimized fully. Vibrational analysis gives a single imaginary frequency (−550.12 cm−1) which corresponds to the N–O bond stretching confirming that the

Cobalt-catalyzed C–H cyanations: Insights into the reaction mechanism and the role of London dispersion

• Eric Detmar,
• Valentin Müller,
• Daniel Zell,
• Lutz Ackermann and
• Martin Breugst

Beilstein J. Org. Chem. 2018, 14, 1537–1545, doi:10.3762/bjoc.14.130

• approach was used to accelerate the calculations [56][57]. For the analysis of the substituent effect, the B3LYP functional with Grimme’s dispersion correction D3 (Becke–Johnson damping) was employed together with the def2-SVP basis set for all non-metals and the def2-TZVP basis set for Co. Vibrational

• analysis verified that each structure was a minimum or transition state (iω < 30 cm−1 were tolerated). Thermal corrections were calculated from unscaled harmonic vibrational frequencies at the same levels of theory and refer to a standard state of 298.15 K and 1 mol L−1. Entropic contributions to the

Solvent-free copper-catalyzed click chemistry for the synthesis of N-heterocyclic hybrids based on quinoline and 1,2,3-triazole

• Martina Tireli,
• Silvija Maračić,
• Stipe Lukin,
• Marina Juribašić Kulcsár,
• Dijana Žilić,
• Mario Cetina,
• Ivan Halasz,
• Silvana Raić-Malić and
• Krunoslav Užarević

Beilstein J. Org. Chem. 2017, 13, 2352–2363, doi:10.3762/bjoc.13.232

• alkyne and triazole products are marked with red and blue asterisks, respectively. For detailed vibrational analysis of these compounds please refer to Table S1, Supporting Information File 1. In situ Raman monitoring of a) mechanochemical formation of triazole 5 using copper(II) acetate monohydrate as

Substitution effect and effect of axle’s flexibility at (pseudo-)rotaxanes

• Friedrich Malberg,
• Jan Gerit Brandenburg,
• Werner Reckien,
• Oldamur Hollóczki,
• Stefan Grimme and
• Barbara Kirchner

Beilstein J. Org. Chem. 2014, 10, 1299–1307, doi:10.3762/bjoc.10.131

• semiempirical methods. In our groups, we investigated the main binding motif for rotaxane systems of the Vögtle [27][28][29][30], Schalley- [29][30][31], and Leigh-type [27]. We performed an energetic and vibrational analysis for the twofold hydrogen bonds in order to understand the binding pattern [28]. A

Use of activated enol ethers in the synthesis of pyrazoles: reactions with hydrazine and a study of pyrazole tautomerism

• Denisa Tarabová,
• Stanislava Šoralová,
• Martin Breza,
• Marek Fronc,
• Wolfgang Holzer and
• Viktor Milata

Beilstein J. Org. Chem. 2014, 10, 752–760, doi:10.3762/bjoc.10.70

• Formalism Polarizable Continuum Model) model including the effect of the solution was applied to optimize the geometries in (m)ethanol and DMSO. The stability of the obtained structures was proven by vibrational analysis (no imaginary vibrations). NMR chemical shifts δ (in ppm) were evaluated from the

A new intermediate in the Prins reaction

• Shinichi Yamabe,
• Takeshi Fukuda and
• Shoko Yamazaki

Beilstein J. Org. Chem. 2013, 9, 476–485, doi:10.3762/bjoc.9.51

• TS geometries were optimized. They were characterized by vibrational analysis, which checked whether the obtained geometries have single imaginary frequencies (ν‡s). From the TSs, reaction paths were traced by the intrinsic reaction coordinate (IRC) method [30][31] to obtain the energy-minimum

SbCl₃-catalyzed one-pot synthesis of 4,4′-diaminotriarylmethanes under solvent-free conditions: Synthesis, characterization, and DFT studies

• Ghasem Rezanejade Bardajee

Beilstein J. Org. Chem. 2011, 7, 135–144, doi:10.3762/bjoc.7.19

• ′-diaminotriarylmethane derivatives in the presence of antimony trichloride as catalyst is described. Triarylmethane derivatives were prepared in good to excellent yields and characterized by elemental analysis, FTIR, 1H and 13C NMR spectroscopic techniques. The structural and vibrational analysis were investigated by

• performing theoretical calculations at the HF and DFT levels of theory by standard 6-31G*, 6-31G*/B3LYP, and B3LYP/cc-pVDZ methods and good agreement was obtained between experimental and theoretical results. Keywords: diaminotriarylmethane; SbCl3; solvent-free reactions; synthesis; vibrational analysis