Tandem Hock and Friedel–Crafts reactions allowing an expedient synthesis of a cyclolignan-type scaffold

• Viktoria A. Ikonnikova,
• Cristina Cheibas,
• Oscar Gayraud,
• Alexandra E. Bosnidou,
• Nicolas Casaretto,
• Gilles Frison and
• Bastien Nay

Beilstein J. Org. Chem. 2024, 20, 162–169, doi:10.3762/bjoc.20.15

• benzyl moiety on the substrate resulted in tandem Friedel–Crafts reactions to form the 1-aryltetraline products. These compounds share a close analogy to the cyclolignan natural products. Experimental observations and a DFT study support the involvement of an aldehyde intermediate during the Friedel

A new oxidatively stable ligand for the chiral functionalization of amino acids in Ni(II)–Schiff base complexes

• Alena V. Dmitrieva,
• Oleg A. Levitskiy,
• Yuri K. Grishin and
• Tatiana V. Magdesieva

Beilstein J. Org. Chem. 2023, 19, 566–574, doi:10.3762/bjoc.19.41

• heating of its MeOH/HCl solution at 60 °C under conditions similar to the ones previously reported for (RCysNi)L4 [42] (see Supporting Information File 1 for details). The corresponding amino acid was obtained, along with the L7 ligand which was recovered in ca. 70% yield and then reused. DFT study The

2,4-Bis(arylethynyl)-9-chloro-5,6,7,8-tetrahydroacridines: synthesis and photophysical properties

• Najeh Tka,
• Mohamed Adnene Hadj Ayed,
• Mourad Ben Braiek,
• Mahjoub Jabli,
• Noureddine Chaaben,
• Kamel Alimi,
• Stefan Jopp and
• Peter Langer

Beilstein J. Org. Chem. 2021, 17, 1629–1640, doi:10.3762/bjoc.17.115

• Dr. Mourad Chemek for the execution of the DFT study. Funding Financial support from the Deutscher Akademischer Austausch Dienst (DAAD) (scholarship for Najeh TKA) is gratefully acknowledged.

Ring-closing metathesis of prochiral oxaenediynes to racemic 4-alkenyl-2-alkynyl-3,6-dihydro-2H-pyrans

• Viola Kolaříková,
• Markéta Rybáčková,
• Martin Svoboda and
• Jaroslav Kvíčala

Beilstein J. Org. Chem. 2020, 16, 2757–2768, doi:10.3762/bjoc.16.226

• ]. The reaction at rt in dichloromethane gave the target product 14 in a moderate 45% isolated yield as a mixture of two diastereoisomers (Scheme 14). Pure diastereoisomers were obtained by column chromatography in 24% and 17% yield, respectively. DFT study of the Diels–Alder reaction of compounds 12b

• obtained two diastereoisomers, we decided to perform a short DFT study of the Diels–Alder reaction between dihydropyran 12b and maleimide 13. We started the study with the optimization of the starting compound. While the optimization of the rigid maleimide 13 was straightforward, 18 conformations had to be

Vicinal difluorination as a C=C surrogate: an analog of piperine with enhanced solubility, photostability, and acetylcholinesterase inhibitory activity

• Yuvixza Lizarme-Salas,
• Alexandra Daryl Ariawan,
• Ranjala Ratnayake,
• Hendrik Luesch,
• Angela Finch and
• Luke Hunter

Beilstein J. Org. Chem. 2020, 16, 2663–2670, doi:10.3762/bjoc.16.216

• . This was achieved by performing a DFT study in the Gaussian software, using the M06-2X level of theory with the 6-311+G(d,p) basis set, parameters similar to those employed by Linclau and co-workers for their studies of vicinal difluoro systems [22]. A set of starting structures of 2 was generated by

Pauson–Khand reaction of fluorinated compounds

• Jorge Escorihuela,
• Daniel M. Sedgwick,
• Alberto Llobat,
• Mercedes Medio-Simón,
• Pablo Barrio and
• Santos Fustero

Beilstein J. Org. Chem. 2020, 16, 1662–1682, doi:10.3762/bjoc.16.138

• substituents such as dimethylaminium, trifluoromethyl, and acetyl favored the β-regioisomer (71B). The 4-fluorine substituted diarylalkynes had a very weak EWG effect yielding an equimolar mixture of both regioisomers. The experimental results were confirmed by a DFT study of the NBO charges of the α-alkyne

Effect of ring size on photoisomerization properties of stiff stilbene macrocycles

• Sandra Olsson,
• Óscar Benito Pérez,
• Magnus Blom and
• Adolf Gogoll

Beilstein J. Org. Chem. 2019, 15, 2408–2418, doi:10.3762/bjoc.15.233

• a six carbon chain) showed some degree of isomerization when irradiated. DFT calculations of the energy differences between the E- and Z-isomers show the same trend as the experimental results. Interestingly the DFT study highlights that the energy difference between the E- and Z-isomers of even the

Different reactivity of phosphorylallenes under the action of Brønsted or Lewis acids: a crucial role of involvement of the P=O group in intra- or intermolecular interactions at the formation of cationic intermediates

• Stanislav V. Lozovskiy,
• Alexander Yu. Ivanov and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2019, 15, 1491–1504, doi:10.3762/bjoc.15.151

• arenes toluene and xylenes (Table 3, entries 2–5). We carried out a DFT study [at the B3LYP/6-311+G(2d,2p) level of theory] for the observed AlCl3-involved reactions (Scheme 9, Scheme 10, Table 4 and Supporting Information File 1 for details of DFT calculations). First, the thermochemistry (ΔG of

Mechanochemistry of supramolecules

• Anima Bose and
• Prasenjit Mal

Beilstein J. Org. Chem. 2019, 15, 881–900, doi:10.3762/bjoc.15.86

• –tert-butylcalix[4]azulene through mortar and pestle grinding of the host and the guest. The structure of the complex was obtained from DFT study. Formation of a 2:2 complex between the supramolecular catalyst and the reagent in the transition state of the [2 + 2]-cycloaddition reaction of 1,2-di

Catalysis of linear alkene metathesis by Grubbs-type ruthenium alkylidene complexes containing hemilabile α,α-diphenyl-(monosubstituted-pyridin-2-yl)methanolato ligands

• Tegene T. Tole,
• Johan H. L. Jordaan and
• Hermanus C. M. Vosloo

Beilstein J. Org. Chem. 2019, 15, 194–209, doi:10.3762/bjoc.15.19

• for 80 °C, at 420 min. It also showed higher TOF at 60, 90 and 100 °C at 420 min. According to a DFT study by Getty et al. [19] the more positively charged the Ru, the slower the initiation rate of the catalyst. The calculated Mulliken atomic charge of Ru in 7 (0.934) is less positive than in 8 (0.976

• , precatalyst 6 showed a low initiation rate. This is also in agreement with the DFT study of Getty et al. [19], i.e., precatalyst 6 (0.988) has more positive Mulliken’s atomic charge on Ru than both 7 (0.934) and 8 (0.976). Its high activity at 110 °C with 69% selectivity is, however, remarkable for linear

Generation of 1,2-oxathiolium ions from (arysulfonyl)- and (arylsulfinyl)allenes in Brønsted acids. NMR and DFT study of these cations and their reactions

• Stanislav V. Lozovskiy,
• Alexander Yu. Ivanov,
• Olesya V. Khoroshilova and
• Aleksander V. Vasilyev

Beilstein J. Org. Chem. 2018, 14, 2897–2906, doi:10.3762/bjoc.14.268

The influence of the cationic carbenes on the initiation kinetics of ruthenium-based metathesis catalysts; a DFT study

• Magdalena Jawiczuk,
• Angelika Janaszkiewicz and
• Bartosz Trzaskowski

Beilstein J. Org. Chem. 2018, 14, 2872–2880, doi:10.3762/bjoc.14.266

Calixazulenes: azulene-based calixarene analogues – an overview and recent supramolecular complexation studies

• Paris E. Georghiou,
• Shofiur Rahman,
• Abdullah Alodhayb,
• Hidetaka Nishimura,
• Jaehyun Lee,
• Atsushi Wakamiya and
• Lawrence T. Scott

Beilstein J. Org. Chem. 2018, 14, 2488–2494, doi:10.3762/bjoc.14.225

• supramolecular binding study recently concluded with OPC4A. These results and a corresponding DFT study are reported herein. Results and Discussion The convenient synthesis of the precursor for OPC4A 5, namely 5,7-diphenylazulene, which is normally a difficult target molecule, was previously described from a

A challenging redox neutral Cp*Co(III)-catalysed alkylation of acetanilides with 3-buten-2-one: synthesis and key insights into the mechanism through DFT calculations

• Andrew Kenny,
• Alba Pisarello,
• Arron Bird,
• Paula G. Chirila,
• Alex Hamilton and
• Christopher J. Whiteoak

Beilstein J. Org. Chem. 2018, 14, 2366–2374, doi:10.3762/bjoc.14.212

• -neutral alternative, obviating the requirement for addition of terminal oxidant (Scheme 1c). Herein, our results from this study will be reported and the difficulties of this translation will be explained through a DFT study of the mechanism, which will also be directly compared with the use of benzamides

• Information File 330: Experimental details and analytical data of new compounds including their original 1H and 13C and COSY spectra and data for all structures obtained from the DFT study. Acknowledgements The authors would like to thank the Department of Biosciences and Chemistry at Sheffield Hallam

Are boat transition states likely to occur in Cope rearrangements? A DFT study of the biogenesis of germacranes

• José Enrique Barquera-Lozada and
• Gabriel Cuevas

Beilstein J. Org. Chem. 2017, 13, 1969–1976, doi:10.3762/bjoc.13.192

DMAP-assisted sulfonylation as an efficient step for the methylation of primary amine motifs on solid support

• Johnny N. Naoum,
• Koushik Chandra,
• Dorit Shemesh,
• R. Benny Gerber,
• Chaim Gilon and
• Mattan Hurevich

Beilstein J. Org. Chem. 2017, 13, 806–816, doi:10.3762/bjoc.13.81

• nucleophilic addition type mechanism, a DFT study was performed. In this study, the effect of collidine and DMAP on the formation of sulfonylamide was evaluated by calculating the energy differences between the reactants and their corresponding intermediates (Figure 4). The calculations include the chlorine

• , namely 1.28 eV. Figure 4b shows the energy diagram for the reaction of o-NBS-Cl with DMAP. The energy difference in this case is much lower, namely only 0.15 eV. The DFT study shows that the energy barrier of the o-NBS-DMAP intermediate is low compared to that of the o-NBS-collidine intermediate. These

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

• of the reaction slugs (by a flow UV cell) and the protocol for GC sampling. A schematic depiction of the experimental system is shown in Figure 2. Physical model generation and refinement The initial model structure and parameters were taken from the earlier published DFT study of the reaction [18

Synthesis of the C8’-epimeric thymine pyranosyl amino acid core of amipurimycin

• Pramod R. Markad,
• Navanath Kumbhar and
• Dilip D. Dhavale

Beilstein J. Org. Chem. 2016, 12, 1765–1771, doi:10.3762/bjoc.12.165

• this regard are in progress. Antifungal antibiotic amipurimycin (1). Conformational analysis of 13 and 14. Geometrically optimized conformation of 12 and 13 respectively by DFT study. Retrosynthesis of 2. Synthesis of 1,3-anhydrosugar 12 and 13. Formation of 2,7-dioxabicyclo[3.2.1]octane 12/13

Pyridylidene ligand facilitates gold-catalyzed oxidative C–H arylation of heterocycles

• Kazuhiro Hata,
• Hideto Ito,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2015, 11, 2737–2746, doi:10.3762/bjoc.11.295

• as a DFT study, indicated unusual stability of gold(III) species stabilized by strong electron donation from the 2-pyridylidene ligand. Thus, the gold(I)-to-gold(III) oxidation process is thought to be facilitated by the highly electron-donating 2-pyridylidene ligand. Keywords: carbene ligand; C–H

Computational study of productive and non-productive cycles in fluoroalkene metathesis

• Markéta Rybáčková,
• Jan Hošek,
• Ondřej Šimůnek,
• Viola Kolaříková and
• Jaroslav Kvíčala

Beilstein J. Org. Chem. 2015, 11, 2150–2157, doi:10.3762/bjoc.11.232

• Marketa Rybackova Jan Hosek Ondrej Simunek Viola Kolarikova Jaroslav Kvicala Department of Organic Chemistry, University of Chemistry and Technology, Technická 5, 166 28 Prague 6, Czech Republic 10.3762/bjoc.11.232 Abstract A detailed DFT study of the mechanism of metathesis of fluoroethene, 1

Mechanism, kinetics and selectivity of selenocyclization of 5-alkenylhydantoins: an experimental and computational study

• Biljana M. Šmit,
• Radoslav Z. Pavlović,
• Dejan A. Milenković and
• Zoran S. Marković

Beilstein J. Org. Chem. 2015, 11, 1865–1875, doi:10.3762/bjoc.11.200

• to the formation of fused bicyclic hydantoins, a computational (DFT) study was carried out. The mechanism of the reaction of 5-alkenylhydantoins with phenylselenyl chloride was examined using the reaction with model substrate 1. The proposed five-step mechanism, starting with an electrophilic

Fe(II)/Et₃N-Relay-catalyzed domino reaction of isoxazoles with imidazolium salts in the synthesis of methyl 4-imidazolylpyrrole-2-carboxylates, its ylide and betaine derivatives

• Ekaterina E. Galenko,
• Olesya A. Tomashenko,
• Alexander F. Khlebnikov,
• Mikhail S. Novikov and
• Taras L. Panikorovskii

Beilstein J. Org. Chem. 2015, 11, 1732–1740, doi:10.3762/bjoc.11.189

• (Scheme 4). Ylide 2a was hydrolyzed with a lower yield due to the high solubility of the salt 14a in water. Betaines 6 can, in principle, exist in tautomeric equilibrium with the corresponding carboxy-substituted ylides 4 and N-heterocyclic carbenes 5. The results of the DFT study of the relative

An unusually stable chlorophosphite: What makes BIFOP–Cl so robust against hydrolysis?

• Roberto Blanco Trillo,
• Jörg M. Neudörfl and
• Bernd Goldfuss

Beilstein J. Org. Chem. 2015, 11, 313–322, doi:10.3762/bjoc.11.36

• . A DFT study of the hydrolysis in BIFOP–Cl verifies a higher repulsive interaction to water and a decreased leaving tendency of the chloride nucleofuge, which is caused by the fenchane units. This high stability of BIFOP–Cl against nucleophiles supports its application as a chiral ligand, for example

Comparing kinetic profiles between bifunctional and binary type of Zn(salen)-based catalysts for organic carbonate formation

• Carmen Martín and
• Arjan W. Kleij

Beilstein J. Org. Chem. 2014, 10, 1817–1825, doi:10.3762/bjoc.10.191

• ) complexes in conjunction with NBu4I for CO2/epoxide coupling reactions [26][27][28][29], proposing for this process the monometallic mechanism depicted in Scheme 2 [26]. Furthermore, a detailed DFT study for this transformation was reported supporting this proposed mechanism [36]. In the catalytic cycle of

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

• can be further advanced by kinetic studies and the isolation and characterization of key intermediates. Keywords: alkyne; azide; Click; copper; CuAAC; DFT study; Huisgen–Meldal–Sharpless cycloaddition; kinetics; reaction mechanism; Introduction In 1893, Michael discovered a reaction between dimethyl

• ) complexes as calculated in a DFT study by Ahlquist and Fokin [125] (transition states with Cu–Cu distances of 2.54 Å for L = X = chloride and 2.64 Å for L = acetylide). They tested copper(I) acetate in the CuAAC model reaction of benzyl azide with phenylacetylene and reported an excellent performance of