Plasma membrane imaging with a fluorescent benzothiadiazole derivative

• Pedro H. P. R. Carvalho,
• Jose R. Correa,
• Karen L. R. Paiva,
• Daniel F. S. Machado,
• Jackson D. Scholten and
• Brenno A. D. Neto

Beilstein J. Org. Chem. 2019, 15, 2644–2654, doi:10.3762/bjoc.15.257

• continuum model (PCM) in which the solute molecule is enclosed in a cavity embedded in a continuum dielectric medium. The optimized geometries of the ground state (S0) in the calculated solvents were then used for the single point TD-DFT calculation using density functionals of different flavors to assess

Small anion-assisted electrochemical potential splitting in a new series of bistriarylamine derivatives: organic mixed valency across a urea bridge and zwitterionization

• Keishiro Tahara,
• Tetsufumi Nakakita,
• Alyona A. Starikova,
• Takashi Ikeda,
• Masaaki Abe and
• Jun-ichi Kikuchi

Beilstein J. Org. Chem. 2019, 15, 2277–2286, doi:10.3762/bjoc.15.220

• band shape and electronic coupling factor of 1+.a Supporting Information Supporting Information File 298: Copies of 1H NMR spectra of new compounds, DFT calculation data, and electrochemical data. Acknowledgements This work was supported in part by JSPS KAKENHI 18K04890 and JP16H06514 in Coordination

Click chemistry towards thermally reversible photochromic 4,5-bisthiazolyl-1,2,3-triazoles

• Chenxia Zhang,
• Kaori Morinaka,
• Mahmut Kose,
• Takashi Ubukata and
• Yasushi Yokoyama

Beilstein J. Org. Chem. 2019, 15, 2161–2169, doi:10.3762/bjoc.15.213

• acetate and toluene. Analysis processes of the thermal back reactions of 1o, 2o and 3o. DFT and TD DFT calculation results of 1c, 2c and 3c and 1H NMR, IR and mass spectra of new compounds. Supporting Information File 434: Additional experimental data and spectra. Acknowledgements This work was supported

Complexation of 2,6-helic[6]arene and its derivatives with 1,1′-dimethyl-4,4′-bipyridinium salts and protonated 4,4'-bipyridinium salts: an acid–base controllable complexation

• Jing Li,
• Qiang Shi,
• Ying Han and
• Chuan-Feng Chen

Beilstein J. Org. Chem. 2019, 15, 1795–1804, doi:10.3762/bjoc.15.173

• main reason for the formation of the stable complex H5·G1. DFT calculation of host–guest complexes To further investigate the complexation mode and structural characteristics of the host–guest complexes, DFT calculations were carried out at the B3LYP/6-31G level of theory for complex H4·G1 (Supporting

• solvents at 298 K. Supporting Information Supporting Information File 499: Experimental, NMR spectra, mass spectra, determination of association constants, X-ray single crystal data and DFT calculation data. Supporting Information File 500: CIF file for H1·G1. Supporting Information File 501: CIF file for

Synthesis, photophysical and electrochemical properties of pyridine, pyrazine and triazine-based (D–π–)₂A fluorescent dyes

• Keiichi Imato,
• Toshiaki Enoki,
• Koji Uenaka and
• Yousuke Ooyama

Beilstein J. Org. Chem. 2019, 15, 1712–1721, doi:10.3762/bjoc.15.167

• , OUK-2 and OUJ-2, respectively, estimated from DFT calculation at the B3LYP/6-31G(d,p) level of theory [47]), Δf is the orientation polarizability, ε is the static dielectric constant, and n is the refractive index of the solvent. The Lippert–Mataga plots (Figure 3) for the three dyes show high

• molecular structures and the molecular orbitals of the three dyes were calculated using the DFT at the B3LYP/6-31G(d,p) level of theory [47]. The results of the DFT calculation for the three dyes indicated that the HOMO is mostly localized on the two (diphenylamino)carbazole moieties containing the

• ), which are in good agreement with the experimental results from the photoabsorption and fluorescence spectral analyses (Figure 2) and the cyclic voltammetry (Figure 5). Thus, the experimental results and the DFT calculation strongly demonstrated that the bathochromic shift of the ICT-based

Mechanochemical amorphization of chitin: impact of apparatus material on performance and contamination

• Thomas Di Nardo and
• Audrey Moores

Beilstein J. Org. Chem. 2019, 15, 1217–1225, doi:10.3762/bjoc.15.119

• systematic study of the effects of a number of medium parameters onto a model reaction, namely the amorphization of chitin where interchain stabilization is greater than 250 kJ/mol based on density functional theory (DFT) calculation [58]. We explored the role of the material of the jar and the ball, ball

Insertion of [1.1.1]propellane into aromatic disulfides

• Robin M. Bär,
• Gregor Heinrich,
• Martin Nieger,
• Olaf Fuhr and
• Stefan Bräse

Beilstein J. Org. Chem. 2019, 15, 1172–1180, doi:10.3762/bjoc.15.114

• the 4-methoxybenzenethiyl radical is either formed faster and/or reacts more rapidly with 1 than the corresponding benzenethiyl radical. The calculated BDE (DFT calculation) of 10e is slightly lower with 49.0 kcal/mol compared to 10a with 54.5 kcal/mol [32]. This difference hints towards the faster

Degenerative xanthate transfer to olefins under visible-light photocatalysis

• Atsushi Kaga,
• Xiangyang Wu,
• Joel Yi Jie Lim,
• Hirohito Hayashi,
• Yunpeng Lu,
• Edwin K. L. Yeow and
• Shunsuke Chiba

Beilstein J. Org. Chem. 2018, 14, 3047–3058, doi:10.3762/bjoc.14.283

• feasible. In contrast, the triplet energy ET of xanthate 1a was estimated as 57.5 kcal/mol by DFT calculation, that is close to those of photocatalysts 7 and 8 (ET = 60.1 kcal/mol [50]), indicating that the process could be initiated by the triplet sensitization pathway [51][52]. This assumption is in

1,8-Bis(dimethylamino)naphthyl-2-ketimines: Inside vs outside protonation

• A. S. Antonov,
• A. F. Pozharskii,
• P. M. Tolstoy,
• A. Filarowski and
• O. V. Khoroshilova

Beilstein J. Org. Chem. 2018, 14, 2940–2948, doi:10.3762/bjoc.14.273

• contribution of the N−H···O IHB to the stabilisation of the E-forms of 5a–7a appears to be small: in the 1H NMR spectra, the NHa signal is shifted to the low field by less than 1 ppm in comparison with Z-4a (Figure 1) [9]; in a DFT calculation, the mutual orientation of C=NH and the OMe groups is not optimal

Unprecedented nucleophile-promoted 1,7-S or Se shift reactions under Pummerer reaction conditions of 4-alkenyl-3-sulfinylmethylpyrroles

• Takashi Go,
• Akane Morimatsu,
• Hiroaki Wasada,
• Genzoh Tanabe,
• Osamu Muraoka,
• Yoshiharu Sawada and
• Mitsuhiro Yoshimatsu

Beilstein J. Org. Chem. 2018, 14, 2722–2729, doi:10.3762/bjoc.14.250

• . Proposed mechanism. Crossover experiment. Lewis acid-catalysed cyclization of diols. Sequential process of sulfanyl-1,6-diyne 1 to 4H-pyrrolo[3,4-g]oxazine 25g. Screening the reaction conditions for the Pummerer reactions. DFT Calculation of the two pathways: from 14 to 15x or from 14 to 21x. Supporting

Determining the predominant tautomeric structure of iodine-based group-transfer reagents by ¹⁷O NMR spectroscopy

• Nico Santschi,
• Cody Ross Pitts,
• Benson J. Jelier and
• René Verel

Beilstein J. Org. Chem. 2018, 14, 2289–2294, doi:10.3762/bjoc.14.203

• residual value (Table 1). Conceivably, this may be due to intermolecular hydrogen bonding with the solvent or other alcohol molecules in the concentrated solution. In fact, including a methanol solvent molecule as a hydrogen-bond donor in the DFT calculation will shift the δcalc in the right direction for

Selective formation of a zwitterion adduct and bicarbonate salt in the efficient CO₂ fixation by N-benzyl cyclic guanidine under dry and wet conditions

• Yoshiaki Yoshida,
• Naoto Aoyagi and
• Takeshi Endo

Beilstein J. Org. Chem. 2018, 14, 2204–2211, doi:10.3762/bjoc.14.194

• characterized in detail by elemental analysis, FTIR-ATR, solid-state NMR, TGA, and DFT calculation. These analytical results obviously revealed the formation of a zwitterion adduct and bicarbonate salt from N-benzyl cyclic guanidine and CO2. Especially, the zwitterion adduct of the monocyclic guanidine

• geometrical structures of 2 and 3 were computed with DFT calculation (Figure 5). In the calculated geometry for 2, the bond length between CO2 and imine nitrogen was 1.548 Å and the bent angle of O–C–O bond was 135.76°. These bond length and angle were fairly similar to that of the zwitterion adduct between

• from 1 under dry (in anhydrous CH3CN) and wet (in CH3CN containing an equimolar amount of water for 1) conditions, respectively. Both of 2 and 3 were isolated as white solids and their structures were characterized in detail by elemental analysis, FTIR-ATR, solid-state NMR, TGA, and DFT calculation

DFT calculations on the mechanism of copper-catalysed tandem arylation–cyclisation reactions of alkynes and diaryliodonium salts

• Tamás Károly Stenczel,
• Ádám Sinai,
• Zoltán Novák and
• András Stirling

Beilstein J. Org. Chem. 2018, 14, 1743–1749, doi:10.3762/bjoc.14.148

• the basis of the mechanism the origin of the stereoselectivity is ascribed to the interaction of the Cu ion with the oxazoline oxygen driving the ring-closure step selectively. Keywords: catalysis; DFT calculation; iodonium salts; reaction mechanism; tandem arylation–cyclisation; Introduction

Design, synthesis and structure of novel G-2 melamine-based dendrimers incorporating 4-(n-octyloxy)aniline as a peripheral unit

• Cristina Morar,
• Pedro Lameiras,
• Attila Bende,
• Gabriel Katona,
• Emese Gál and
• Mircea Darabantu

Beilstein J. Org. Chem. 2018, 14, 1704–1722, doi:10.3762/bjoc.14.145

• direction to the other five, caused, probably, by the propeller orientation (Figure 1) of the three covalent junctions around the benzene core. In contrast, the energetic minimum of the ionic analogue 7b could be accessed in a gradual approach only. Thus, we had to start from a preliminary DFT calculation

• the G-1 dendritic branches to the m-trivalent core. Conclusion Starting from 4-(n-octyloxy)aniline, the five-step orthogonal convergent synthesis of a new seven terms series of G-2 melamine based-dendrimers was achieved in overall yields ranging between 29 and 79%. By means of DFT calculation in

Hypervalent organoiodine compounds: from reagents to valuable building blocks in synthesis

• Gwendal Grelier,
• Benjamin Darses and
• Philippe Dauban

Beilstein J. Org. Chem. 2018, 14, 1508–1528, doi:10.3762/bjoc.14.128

• supported by DFT calculation have led to propose that the rate-determining step of the process would be the ligand exchange between TFA and the O-enolate (Scheme 41) [79]. The resulting cationic intermediate 88 could rapidly evolve through a [3,3] rearrangement. Even though the C-enolate 89 is more stable

Stereoselective nucleophilic addition reactions to cyclic N-acyliminium ions using the indirect cation pool method: Elucidation of stereoselectivity by spectroscopic conformational analysis and DFT calculations

• Koichi Mitsudo,
• Junya Yamamoto,
• Tomoya Akagi,
• Atsuhiro Yamashita,
• Masahiro Haisa,
• Kazuki Yoshioka,
• Hiroki Mandai,
• Koji Ueoka,
• Christian Hempel,
• Jun-ichi Yoshida and
• Seiji Suga

Beilstein J. Org. Chem. 2018, 14, 1192–1202, doi:10.3762/bjoc.14.100

• selectivity has not been clear, it is probably due to steric repulsion between the phenyl and Boc groups. A distortion of the Boc group in C5 was also suggested by DFT calculation (see Supporting Information File 1). The reaction of 6-methyl-substituted N-acyliminium cation C6 bearing a methyl group, which is

Two novel blue phosphorescent host materials containing phenothiazine-5,5-dioxide structure derivatives

• Feng-Ming Xie,
• Qingdong Ou,
• Qiang Zhang,
• Jiang-Kun Zhang,
• Guo-Liang Dai,
• Xin Zhao and
• Huai-Xin Wei

Beilstein J. Org. Chem. 2018, 14, 869–874, doi:10.3762/bjoc.14.73

• phenyl ring. The LUMOs are mostly localized on the phenothiazine-5,5-dioxide, based on the DFT calculation. There is a small degree of spatial overlap between the HOMO and LUMO in these two molecules. The separated HOMO and LUMO resulted from the strong electron-donating nature of the carbazole unit and

D–A–D-type orange-light emitting thermally activated delayed fluorescence (TADF) materials based on a fluorenone unit: simulation, photoluminescence and electroluminescence studies

• Lin Gan,
• Xianglong Li,
• Xinyi Cai,
• Kunkun Liu,
• Wei Li and
• Shi-Jian Su

Beilstein J. Org. Chem. 2018, 14, 672–681, doi:10.3762/bjoc.14.55

• , but also a weaker oscillator strength from its local excited (LE) states. It could be considered that 2 has a better configuration, which is advantageous to intramolecular charge transfer compared with 1, which coincides with the conclusion from DFT calculation. The PL spectra of the materials in

• solution. However, the PL spectrum of 2 is slightly blue-shifted from its PL spectrum in toluene, while 1:CBP shows alike spectra with 1 in toluene. It could be considered as the solid-state solvation effect [21], as 2 and 1 have different dipole moment of 1.814 D and 3.501 D, respectively from DFT

• calculation, owing to their different configurations. The doped film 2:CBP shows a typical TADF behavior as shown in Figure 4b, according to the time-resolved transient photoluminescence decay measurement. The proportion of delayed fluorescence increases rapidly with improved temperature from 77 to 250 K and

The selective electrochemical fluorination of S-alkyl benzothioate and its derivatives

• Shunsuke Kuribayashi,
• Tomoyuki Kurioka,
• Shinsuke Inagi,
• Ho-Jung Lu,
• Biing-Jiun Uang and
• Toshio Fuchigami

Beilstein J. Org. Chem. 2018, 14, 389–396, doi:10.3762/bjoc.14.27

• these compounds have rather high oxidation potentials. DFT calculation of 1a indicated that the highest occupied molecular orbital (HOMO) is located at the sulfur atom (Figure 2). Although sulfur atoms are easily oxidized, the oxidation potential of 1a was found to be extremely high, that is due to the

• both the sulfur atom and the α-phenyl group, which was suggested by DFT calculation (Figure 3). However, regardless of the discharging sites, the same cationic intermediate is generated through two-electron oxidation and deprotonation (in α position to both the sulfur atom and phenyl group), which

• forms the α-fluorinated product 2h selectively. In contrast, the electron transfer of 1i seems to take place mainly from the β-phenyl group as indicated by DFT calculation (Figure 3). As shown in Scheme 1, an electron transfer from the β-phenyl group in 1i followed by deprotonation and an additional

A permutation approach to the assignment of the configuration to diastereomeric tetrads by comparison of experimental and ab initio calculated differences in NMR data

• Przemysław J. Boratyński

Beilstein J. Org. Chem. 2017, 13, 2478–2485, doi:10.3762/bjoc.13.245

• from DFT calculation. Then, chemical shift listings are arranged into 24 different arrays corresponding to all permutations. For example data of experimental compounds a, b, c, and d are arranged to computed data for RR, RS, SR, and SS isomers in permutation 1, respectively, RS, RR, SR, and SS in

• are more likely to be accurately modeled by DFT calculation. Reinforcing computational methods by extending the basis set to 6-311G++(2d,2p) for both optimization and NMR calculation steps, as well as applying the MPW1PW91 functional (compounds 1–3) did not affect the comparison significantly. However

• the algorithm a permutation with a highest rank is identified. The major limitation is how accurately the experiment is predicted by the DFT calculation. This is, however, a central problem and any data processing will fail in cases where the computed data do not agree with the experiment

Synthesis and photophysical properties of novel benzophospholo[3,2-b]indole derivatives

• Mio Matsumura,
• Mizuki Yamada,
• Atsuya Muranaka,
• Misae Kanai,
• Naoki Kakusawa,
• Daisuke Hashizume,
• Masanobu Uchiyama and
• Shuji Yasuike

Beilstein J. Org. Chem. 2017, 13, 2304–2309, doi:10.3762/bjoc.13.226

• tetracyclic moieties are planar. The benzophosphole-fused indoles, such as phosphine oxide, phospholium salt, and borane complex, exhibited strong photoluminescence in dichloromethane (Φ = 67–75%). Keywords: benzophospholo[3,2-b]indole; DFT calculation; molecular structure; phosphole derivatives

Self-optimisation and model-based design of experiments for developing a C–H activation flow process

• Alexander Echtermeyer,
• Yehia Amar,
• Jacek Zakrzewski and
• Alexei Lapkin

Beilstein J. Org. Chem. 2017, 13, 150–163, doi:10.3762/bjoc.13.18

• difference between initial guess and final value is significant, which might be caused be the simplifications employed for computing the guesses and the uncertainty of the DFT calculation in the exponentially amplified van’t Hoff equation. The 95% confidence intervals for the parameters of reaction j = 0 are

Protonated paramagnetic redox forms of di-o-quinone bridged with p-phenylene-extended TTF: A EPR spectroscopy study

• Nikolay O. Chalkov,
• Vladimir K. Cherkasov,
• Gleb A. Abakumov,
• Andrey G. Starikov and
• Viacheslav A. Kuropatov

Beilstein J. Org. Chem. 2016, 12, 2450–2456, doi:10.3762/bjoc.12.238

• paramagnetic redox forms of quinone 1 display a rather large spin density on the central p-phenylene fragment. Such delocalization is accessible if the dihedral angle between the p-phenylene and o-semiquinone rings is close to zero. This is in a good agreement with the DFT calculation data at the UB3LYP/6-311

Star-shaped and linear π-conjugated oligomers consisting of a tetrathienoanthracene core and multiple diketopyrrolopyrrole arms for organic solar cells

• Hideaki Komiyama,
• Chihaya Adachi and
• Takuma Yasuda

Beilstein J. Org. Chem. 2016, 12, 1459–1466, doi:10.3762/bjoc.12.142

• consistent with the increment in the oscillator strength revealed by the DFT calculation results. The ICT absorption peaks are slightly red-shifted and broadened in the solid thin films as compared to those in the chloroform solutions, which can be ascribed to molecular aggregation in the condensed solid

Molecular weight control in organochromium olefin polymerization catalysis by hemilabile ligand–metal interactions

• Stefan Mark,
• Hubert Wadepohl and
• Markus Enders

Beilstein J. Org. Chem. 2016, 12, 1372–1379, doi:10.3762/bjoc.12.131

• -ray diffraction data could be obtained from the active form of chromium polymerization catalysts [61][62][63]. However, DFT calculation is well suitable for studying such interactions. By such methods it is not only possible to estimate the binding energy but also to compare it with that of ethylene