Substitution reactions in the acenaphthene analog of quino[7,8-h]quinoline and an unusual synthesis of the corresponding acenaphthylenes by tele-elimination

• Ekaterina V. Kolupaeva,
• Narek A. Dzhangiryan,
• Alexander F. Pozharskii,
• Oleg P. Demidov and
• Valery A. Ozeryanskii

Beilstein J. Org. Chem. 2024, 20, 243–253, doi:10.3762/bjoc.20.24

• in a 2:1 ratio leads to the formation of co-crystals, in which, as judged by the X-ray data, the supramolecular organization is again in action (Figure 4). Two molecules of the base are almost parallel to each other (the distance between the π-systems of two molecular planes is 3.551 Å with the

• -axis is shown). Selected images of the supramolecular organization of two molecules of base 5 held by 4,6-dichlororesorcinol in an almost parallel manner showing side view (а), view with the resorcinol molecule directed to the viewer (b), and view above the azaarene cycles showing their almost complete

Photochromic derivatives of indigo: historical overview of development, challenges and applications

• Gökhan Kaplan,
• Zeynel Seferoğlu and
• Daria V. Berdnikova

Beilstein J. Org. Chem. 2024, 20, 228–242, doi:10.3762/bjoc.20.23

• melting point of indigo is bifurcated intra- and intermolecular hydrogen bonding [11], and face-to-face π–π stacking of parallel aromatic rings (Figure 2) [12]. Single crystal X-ray diffraction analysis showed that the indigo molecule is almost planar and exists in the E-conformation. The central C=C bond

Electron-beam-promoted fullerene dimerization in nanotubes: insights from DFT computations

• Laura Abella,
• Gerard Novell-Leruth,
• Josep M. Ricart,
• Josep M. Poblet and
• Antonio Rodríguez-Fortea

Beilstein J. Org. Chem. 2024, 20, 92–100, doi:10.3762/bjoc.20.10

• slightly larger than 2 Å in all three cases. Finally, formation of dimer 1-Cs is exothermic for the radical cation profile, but moderately endothermic for the neutral dimer, as previously observed. As general trends, we find that the radical cation profiles are qualitatively parallel with some minimal

Preparing a liquid crystalline dispersion of carbon nanotubes with high aspect ratio

• Keiko Kojima,
• Nodoka Kosugi,
• Hirokuni Jintoku,
• Kazufumi Kobashi and
• Toshiya Okazaki

Beilstein J. Org. Chem. 2024, 20, 52–58, doi:10.3762/bjoc.20.7

• ][30]. If the DWCNTs align parallel to the long axis of the spindle droplet, it is referred to as a homogenous tactoid. Conversely, if the DWCNTs align from one pole to another, it is called a bipolar tactoid. Figure 3 illustrates the aspect ratio of the tactoids (R/r) as a function of the tactoid

• effect [15][33][34]. As a result, the volume fraction of DWCNTs at the edge increased. Notably, the widths of bundled DWCNTs at the edge were larger than in the inner region (Figure 5b,c). The direction of the bundled DWCNTs near the film surface were parallel to the shear direction in both regions. Due

• polarizers (white double arrows). Scale bars are 400 µm. (c) Polarized optical absorption spectra with different angles ranging from 0° (red) to 90° (blue). The sear direction and polarizer are parallel at 0°. (d) SEM image of the DWCNT film. Blue outlined arrows indicate the shear direction of bar-coating

Charge carrier transport in perylene-based and pyrene-based columnar liquid crystals

• Alessandro L. Alves,
• Simone V. Bernardino,
• Carlos H. Stadtlober,
• Edivandro Girotto,
• Giliandro Farias,
• Rodney M. do Nascimento,
• Sergio F. Curcio,
• Thiago Cazati,
• Marta E. R. Dotto,
• Juliana Eccher,
• Leonardo N. Furini,
• Hugo Gallardo,
• Harald Bock and
• Ivan H. Bechtold

Beilstein J. Org. Chem. 2023, 19, 1755–1765, doi:10.3762/bjoc.19.128

• the charge carrier mobility (parallel vs perpendicular to the columnar axis) of up to ten orders of magnitude [3][4][5][6][7]. In 1994, Adam and collaborators obtained a hole-mobility of up to 0.1 cm2 V−1 s−1 for a triphenylene-based columnar liquid crystal [8], motivating intense research activity to

Effects of the aldehyde-derived ring substituent on the properties of two new bioinspired trimethoxybenzoylhydrazones: methyl vs nitro groups

• Dayanne Martins,
• Roberta Lamosa,
• Talis Uelisson da Silva,
• Carolina B. P. Ligiero,
• Sérgio de Paula Machado,
• Daphne S. Cukierman and
• Nicolás A. Rey

Beilstein J. Org. Chem. 2023, 19, 1713–1727, doi:10.3762/bjoc.19.125

• antiparallel dimers (marked as *) sandwiched between two non-parallel molecules. The planes in hdz-NO2 present similar intermolecular interactions, but they grow as (101) planes. The columns also present the antiparallel dimers, but they are intercalated by antiparallel slipped molecules (Figure 2C). The

• spectrum of this precursor at pH 3.8 (dotted dark yellow curve). On the other hand, under similar arguments, the constituent at 284 nm is probably related to a TMP-based transition. In contrast, the intense component at 307 nm has no parallel in the spectra of precursors and was consequently attributed to

Benzoimidazolium-derived dimeric and hydride n-dopants for organic electron-transport materials: impact of substitution on structures, electrochemistry, and reactivity

• Swagat K. Mohapatra,
• Khaled Al Kurdi,
• Samik Jhulki,
• Georgii Bogdanov,
• John Bacsa,
• Maxwell Conte,
• Tatiana V. Timofeeva,
• Seth R. Marder and
• Stephen Barlow

Beilstein J. Org. Chem. 2023, 19, 1651–1663, doi:10.3762/bjoc.19.121

• endergonic dimer-to-SC ET; subsequent rapid cleavage of the odd-electron dimer cation affords the stable monomer cation and an odd-electron monomer, the latter then undergoing an exergonic ET to another SC molecule. The “ET-first” mechanism occurs in parallel with the “cleavage-first” mechanism for many of

Organic thermally activated delayed fluorescence material with strained benzoguanidine donor

• Alexander C. Brannan,
• Elvie F. P. Beaumont,
• Nguyen Le Phuoc,
• George F. S. Whitehead,
• Mikko Linnolahti and
• Alexander S. Romanov

Beilstein J. Org. Chem. 2023, 19, 1289–1298, doi:10.3762/bjoc.19.95

• benzoguanidine donor ligands around the central 4,6-dicyanobenzene core. Unlike the 4CzIPN compound, the 4BGIPN emitter can crystallize in a chiral P21 space group due to the parallel and antiparallel orientation of the benzoguanidine donors with respect to each other, lack of C2 rotational symmetry and extended

Selective and scalable oxygenation of heteroatoms using the elements of nature: air, water, and light

• Damiano Diprima,
• Hannes Gemoets,
• Stefano Bonciolini and
• Koen Van Aken

Beilstein J. Org. Chem. 2023, 19, 1146–1154, doi:10.3762/bjoc.19.82

• suppress the photochemical reaction while carrying out another light-induced transformation. Aromatic additives (Table 2): In parallel we observed the significant influence on the reaction rate when the substrate contained an aromatic moiety (e.g., the thioanisole oxidation is over 10 times faster than the

Eschenmoser coupling reactions starting from primary thioamides. When do they work and when not?

• Lukáš Marek,
• Jiří Váňa,
• Jan Svoboda and
• Jiří Hanusek

Beilstein J. Org. Chem. 2023, 19, 808–819, doi:10.3762/bjoc.19.61

• desirable ECR product 9a in 62% or 55% yield (entries 3 and 7 in Table 1) together with other decomposition products from which only thiobenzamide and benzonitrile were identified. In pure trimethyl phosphite (Table 1, entry 8) that acts simultaneously as polar solvent and mild thiophile, the parallel

• where triethylamine behaves as a much stronger base. A much weaker base – solid KHCO3 – is probably still strong enough to generate free imidothioates 6a,b''' which undergo parallel base-catalyzed elimination (minor route to nitriles) and intramolecular proton-transfer between the carbon and nitrogen to

Palladium-catalyzed enantioselective three-component synthesis of α-arylglycine derivatives from glyoxylic acid, sulfonamides and aryltrifluoroborates

• Bastian Jakob,
• Nico Schneider,
• Luca Gengenbach and
• Georg Manolikakes

Beilstein J. Org. Chem. 2023, 19, 719–726, doi:10.3762/bjoc.19.52

• situ generation of reactive imine species, we have disclosed iron- and bismuth-catalyzed three-component reactions for the synthesis of α-arylglycines [14][15][16], in which the arylboronic acid could be replaced with an electron-rich (hetero)arene as nucleophile. In parallel, we have developed

Synthesis, structure, and properties of switchable cross-conjugated 1,4-diaryl-1,3-butadiynes based on 1,8-bis(dimethylamino)naphthalene

• Semyon V. Tsybulin,
• Ekaterina A. Filatova,
• Alexander F. Pozharskii,
• Valery A. Ozeryanskii and
• Anna V. Gulevskaya

Beilstein J. Org. Chem. 2023, 19, 674–686, doi:10.3762/bjoc.19.49

• formally symmetrical structure of diynes 5, naphthalene rings A and B of molecules 5b and 5d differ in their structural parameters. At the same time, the monomer fragments of the nitro derivative 5e are identical. In the case of 5e, the naphthalene rings lie in parallel planes, while in crystals of 5b and

Combretastatins D series and analogues: from isolation, synthetic challenges and biological activities

• Jorge de Lima Neto and
• Paulo Henrique Menezes

Beilstein J. Org. Chem. 2023, 19, 399–427, doi:10.3762/bjoc.19.31

• convergent route by which it was possible to reach both, compound 2 and 1. Initially, the authors prepared the protected alcohol 66 from aldehyde 52 in a linear sequence (Scheme 12). In parallel, the monobenzylation of 3,4-dihydroxybenzaldehyde (67), followed by chain elongation using the Wittig reaction

• proved to be important for the selectivity of the reaction, where significant cleavage of the benzyl group resulted when ethanol was the solvent of choice. Subsequent ester hydrolysis gave compound 112 (Scheme 22) [55]. In parallel, a Still–Gennari olefination using aldehyde 52 lead to the cis-alkene 113

Strategies to access the [5-8] bicyclic core encountered in the sesquiterpene, diterpene and sesterterpene series

• Cécile Alleman,
• Charlène Gadais,
• Laurent Legentil and
• François-Hugues Porée

Beilstein J. Org. Chem. 2023, 19, 245–281, doi:10.3762/bjoc.19.23

• in α-position to the keto function. This terminal double bond prefigures the late RCM cyclization. trans-Hydrindanone 87 was isolated as a single diastereomer and possesses 5 out of the 10 stereogenic centers of nitidasin (93). In parallel, (−)-citronellene (88) was converted into derivative 89

Inclusion complexes of the steroid hormones 17β-estradiol and progesterone with β- and γ-cyclodextrin hosts: syntheses, X-ray structures, thermal analyses and API solubility enhancements

• Alexios I. Vicatos,
• Zakiena Hoossen and
• Mino R. Caira

Beilstein J. Org. Chem. 2022, 18, 1749–1762, doi:10.3762/bjoc.18.184

• host–guest complexation, as a consequence of a mutual-induced fit of host and guest molecules [39]. With reference to γ-CD·PRO, the asymmetric unit (ASU) comprises three pairs of glucose rings that generate three complete γ-CD molecules when rotation of these units around the four-fold axis parallel to

• to the cavities of the γ-CD molecules. The distinct packing arrangement of the repeat unit of the host molecules in γ-CD·PRO. The four-fold axis (blue line) runs through the centre of the channel, parallel to the c-axis. The water molecules are omitted for clarity. A stereoscopic view of γ-CD·PRO

Inline purification in continuous flow synthesis – opportunities and challenges

• Jorge García-Lacuna and
• Marcus Baumann

Beilstein J. Org. Chem. 2022, 18, 1720–1740, doi:10.3762/bjoc.18.182

• chromatography system which utilizes multiple columns in parallel with a series of valves to stagger the injection of crude material to each of the column lines. The columns are filled with a diethylaminopropyl-functionalized polymer, followed by an UV–vis detector to identify and separate the different peaks

Navigating and expanding the roadmap of natural product genome mining tools

• Friederike Biermann,
• Sebastian L. Wenski and
• Eric J. N. Helfrich

Beilstein J. Org. Chem. 2022, 18, 1656–1671, doi:10.3762/bjoc.18.178

• prediction but are no longer interpretable as a result of their high level of abstraction [73]. NeuRiPP, for instance, utilizes a parallel convolutional neural network to predict novel RiPP precursor genes independent of their RiPP family. The neural network is trained on a RiPP precursor training set that

Comparison of crystal structure and DFT calculations of triferrocenyl trithiophosphite’s conformance

• Ruslan P. Shekurov,
• Mikhail N. Khrizanforov,
• Ilya A. Bezkishko,
• Tatiana P. Gerasimova,
• Almaz A. Zagidullin,
• Daut R. Islamov and
• Vasili A. Miluykov

Beilstein J. Org. Chem. 2022, 18, 1499–1504, doi:10.3762/bjoc.18.157

• value is predicted for one of the gauche S–Fc bonds in the tgg conformer (−60°), whereas the second one is almost parallel to LEP (8°). The energy difference between the considered conformations is quite small, suggesting other factors playing a significant role. The highest energy predicted for the ggg

On drug discovery against infectious diseases and academic medicinal chemistry contributions

• Yves L. Janin

Beilstein J. Org. Chem. 2022, 18, 1355–1378, doi:10.3762/bjoc.18.141

• , parallel/combinatorial synthesis, multicomponent chemistry, metal-catalyzed coupling reactions as well as NMR, preparative/analytical liquid chromatography and mass spectrometry). – An improved understanding of molecular pharmacology along with in vitro or in vivo assays to detect various aspects of drug

Scope of tetrazolo[1,5-a]quinoxalines in CuAAC reactions for the synthesis of triazoloquinoxalines, imidazoloquinoxalines, and rhenium complexes thereof

• Laura Holzhauer,
• Chloé Liagre,
• Olaf Fuhr,
• Nicole Jung and
• Stefan Bräse

Beilstein J. Org. Chem. 2022, 18, 1088–1099, doi:10.3762/bjoc.18.111

• equivalents, no more triazole product could be isolated; the yield of the imidazole product was only slightly affected. In contrast, an increase in the alkyne amount led to a noticeable improvement of the yield from 10% up to 62%. In parallel, the imidazole formation decreased from 22% to 13% under the same

• '-c]quinoxaline (24) was reacted with alkynes under Cu(I) triflate catalysis (see Scheme 5), CuAAC and denitrogenative annulation were observed in parallel to form triazoloimidazoquinoxalines (TIQs) as the main product, which have not been described in the literature yet. It remains unclear if one of

First example of organocatalysis by cathodic N-heterocyclic carbene generation and accumulation using a divided electrochemical flow cell

• Daniele Rocco,
• Ana A. Folgueiras-Amador,
• Richard C. D. Brown and
• Marta Feroci

Beilstein J. Org. Chem. 2022, 18, 979–990, doi:10.3762/bjoc.18.98

• abbreviations for the multiplicity of the peaks are used: s (singlet), d (doublet), t (triplet), q (quartet) and m (multiplet). Parallel plate divided flow cell See Figure 3 for an expanded view of the electrochemical cell components. The details about the dimensions of each cell component are reported

• elsewhere [36]. General procedure for the synthesis of 1-butyl-3-methyl-1H-imidazole-2(3H)-thione Constant current electrolyzes (I = 134 mA) were carried out using a parallel plate divided cell. Anolyte (25 mL) and catholyte (20 mL) were separated through a Nafion® 438 membrane. The anode material was

• (s, 3H), 1.70–1.59 (m, 2H), 1.42–1.24 (m, 2H), 0.92 (t, J = 7.2 Hz, 3H) ppm; 13C NMR (CDCl3) δ 153.1, 111.3, 110.2, 43.5, 31.1, 30.5, 19.9, 13.6 ppm. General procedure for dimerization of trans cinnamaldehyde Constant current electrolyzes (I = 134 mA) were carried out using a parallel plate divided

Electrochemical and spectroscopic properties of twisted dibenzo[g,p]chrysene derivatives

• Tomoya Imai,
• Ryuhei Akasaka,
• Naruhiro Yoshida,
• Toru Amaya and
• Tetsuo Iwasawa

Beilstein J. Org. Chem. 2022, 18, 963–971, doi:10.3762/bjoc.18.96

• . Optimizations of DBC-H(56°)-1 and DBC-H(56°)-2 based on DFT calculations were performed by fixing the atoms, as described above [56]. The conformations of the MeO group in DBC-H(56°)-1 and DBC-H(56°)-2 are nearly perpendicular (98.3°) to and parallel (179.8°) to the benzene ring, respectively (Figure 3 and

• investigated by comparison of DBC-H(56°)-1 (perpendicular to the benzene ring, 98.3°) with DBC-H(56°)-2 (parallel to the benzene ring, 179.8°). Consequently, both the HOMO and LUMO levels of DBC-H(56°)-2 are higher than those of DBC-H(56°)-1 by −0.40 eV and −0.37 eV, respectively. This is likely attributed by

• the effect of conjugation for the orbital of an oxygen atom as shown in the schematic drawing in Figure 3. When the conformation of the MeO group is almost parallel to the benzene ring, the strong orbital interaction between the orbitals on the oxygen and adjacent carbon atoms is possible in HOMO (the

Efficient production of clerodane and ent-kaurane diterpenes through truncated artificial pathways in Escherichia coli

• Fang-Ru Li,
• Xiaoxu Lin,
• Qian Yang,
• Ning-Hua Tan and
• Liao-Bin Dong

Beilstein J. Org. Chem. 2022, 18, 881–888, doi:10.3762/bjoc.18.89

• tested the fermentation time course of DL10004 and DL10006. Based on the above established fermentation conditions, including the ratios of ISO/DMAA and the concentrations of glycerol and IPTG, we performed a sequence of parallel assays to determine the best fermentation length. Considering the inherent

Synthesis of novel alkynyl imidazopyridinyl selenides: copper-catalyzed tandem selenation of selenium with 2-arylimidazo[1,2-a]pyridines and terminal alkynes

• Mio Matsumura,
• Kaho Tsukada,
• Kiwa Sugimoto,
• Yuki Murata and
• Shuji Yasuike

Beilstein J. Org. Chem. 2022, 18, 863–871, doi:10.3762/bjoc.18.87

• torsion angle of 10.28°. 2-Phenylimidazo[1,2-a]pyridine moieties of neighboring molecules were arranged into slipped-parallel π-stacks with head-to-tail or head-to-head orientations. The distances between parallel mean planes were 3.427 and 3.428 Å (Figure 2b). To demonstrate the efficiency and to broaden

Site-selective reactions mediated by molecular containers

• Rui Wang and
• Yang Yu

Beilstein J. Org. Chem. 2022, 18, 309–324, doi:10.3762/bjoc.18.35

• (Figure 1c). This kind of unusual site-selectivity originated from the fixed orientation of the guest substrates confined to the cage host A before the reaction. Force-field calculations showed that the guest substrates 1 and 2 were parallel to each other with the double bond of 2 in close contact with