The charge-assisted hydrogen-bonded organic framework (CAHOF) self-assembled from the conjugated acid of tetrakis(4-aminophenyl)methane and 2,6-naphthalenedisulfonate as a new class of recyclable Brønsted acid catalysts

• Svetlana A. Kuznetsova,
• Alexander S. Gak,
• Yulia V. Nelyubina,
• Vladimir A. Larionov,
• Han Li,
• Michael North,
• Vladimir P. Zhereb,
• Alexander F. Smol'yakov,
• Artem O. Dmitrienko,
• Michael G. Medvedev,
• Igor S. Gerasimov,
• Ashot S. Saghyan and
• Yuri N. Belokon

Beilstein J. Org. Chem. 2020, 16, 1124–1134, doi:10.3762/bjoc.16.99

• polymeric matrix and the low availability of the active sites to the substrates due to diffusion problems. Additionally, the self-association of catalytic centers on flexible polymeric chains may negatively influence the expected activity of the immobilized catalyst. Moreover, the degradation of cross

• structure as depicted in Scheme 1. A crystal of the compound was grown by diffusion of water into a solution of F-1 in DMSO. The results of the X-ray diffraction analysis are shown in Figure 1. The single crystal material of F-1 (F-1a phase) was in the monoclinic space group P21/c, with the lattice

Synthesis of esters of diaminotruxillic bis-amino acids by Pd-mediated photocycloaddition of analogs of the Kaede protein chromophore

• Esteban P. Urriolabeitia,
• Pablo Sánchez,
• Alexandra Pop,
• Cristian Silvestru,
• Eduardo Laga,
• Ana I. Jiménez and
• Carlos Cativiela

Beilstein J. Org. Chem. 2020, 16, 1111–1123, doi:10.3762/bjoc.16.98

• emitting diodes (LEDs) were purchased from Topbright. X-ray crystallography Single crystals of 2c and 4a of suitable quality for X-ray diffraction measurements were grown by slow diffusion of n-pentane into CH2Cl2 solutions of the crude product at –18 °C for several weeks. One selected single crystal was

Fabclavine diversity in Xenorhabdus bacteria

• Sebastian L. Wenski,
• Harun Cimen,
• Natalie Berghaus,
• Sebastian W. Fuchs,
• Selcuk Hazir and
• Helge B. Bode

Beilstein J. Org. Chem. 2020, 16, 956–965, doi:10.3762/bjoc.16.84

• this work, the inhibitory activity of the wild type and the promoter-exchange mutants (induced and non-induced) were analyzed against the human pathogens Escherichia coli, Staphylococcus aureus, Enterococcus faecalis, and Klebsiella pneumoniae by agar well-diffusion bioassays (Table 3). Briefly, cell

• : non-induced, ind: induced) in mm against the human pathogens Escherichia coli (a, ATCC 25922), Staphylococcus aureus (b, ATCC 29213), Enterococcus faecalis (c, ATCC 29212), and Klebsiella pneumoniae (d, ATCC 700603). The corresponding agar well-diffusion bioassays were performed three times, with ten

Towards triptycene functionalization and triptycene-linked porphyrin arrays

• Gemma M. Locke,
• Keith J. Flanagan and
• Mathias O. Senge

Beilstein J. Org. Chem. 2020, 16, 763–777, doi:10.3762/bjoc.16.70

• for C102H88N4O4Si2Zn, 1552.5636; found, 1552.5616. Crystal structure determinations Crystals were grown following the protocol developed by Hope by dissolving the compound in CH2Cl2 and layering with a MeOH for liquid–liquid diffusion [52]. Single crystal X-ray diffraction data for all compounds were

Synthesis of C₇₀-fragment buckybowls bearing alkoxy substituents

• Yumi Yakiyama,
• Shota Hishikawa and
• Hidehiro Sakurai

Beilstein J. Org. Chem. 2020, 16, 681–690, doi:10.3762/bjoc.16.66

• vapour diffusion method using CHCl3/hexane conditions. Figure 2 shows the crystal structure of 5a. The crystal was obtained as a racemic compound containing a pair of two enantiomers defined by bowl chirality [26], as a result of the rapid bowl inversion under the crystallization conditions. 5a formed a

Towards the total synthesis of chondrochloren A: synthesis of the (Z)-enamide fragment

• Jan Geldsetzer and
• Markus Kalesse

Beilstein J. Org. Chem. 2020, 16, 670–673, doi:10.3762/bjoc.16.64

• (Cmc5) by the groups of Höfle and Reichenbach in 2003 [12]. This PKS/NRPS-derived natural product shows only weak antibiotic effects in agar diffusion tests against Micrococcus luteus, Schizosaccharomyces pombe, Bacillus subtilis and Staphylococcus aureus [12]. The relative and absolute stereochemistry

Direct borylation of terrylene and quaterrylene

• Haruka Kano,
• Keiji Uehara,
• Kyohei Matsuo,
• Hironobu Hayashi,
• Hiroko Yamada and
• Naoki Aratani

Beilstein J. Org. Chem. 2020, 16, 621–627, doi:10.3762/bjoc.16.58

• singlet peaks at 8.58, 8.37 and 8.23 ppm due to aromatic protons. The structure of TB4 was unambiguously revealed by single crystal X-ray diffraction analysis (Figure 2). The crystals suitable for X-ray diffraction were obtained by vapor diffusion of hexane into a solution of TB4 in CH2Cl2. The terrylene

A systematic review on silica-, carbon-, and magnetic materials-supported copper species as efficient heterogeneous nanocatalysts in “click” reactions

• Pezhman Shiri and
• Jasem Aboonajmi

Beilstein J. Org. Chem. 2020, 16, 551–586, doi:10.3762/bjoc.16.52

• /mechanical stability, and good adsorption capacity. They also contain an ordered porous network that is appropriate for the free diffusion of reactants and reaction products [24]. In this regard, various functionalized SiO2 nanoparticles were employed in diverse organic reactions, including Suzuki–Miyaura

• thicker layers of Cu on Au nanoparticles. Other findings in this study were: a) copper leaching decreased using gold nanoparticles, b) increasing the dendron generation increased the diffusion resistance. As shown in Scheme 5, a silica nanomaterial was decorated with a novel copper complex of poly(N

Six-fold C–H borylation of hexa-peri-hexabenzocoronene

• Mai Nagase,
• Kenta Kato,
• Akiko Yagi,
• Yasutomo Segawa and
• Kenichiro Itami

Beilstein J. Org. Chem. 2020, 16, 391–397, doi:10.3762/bjoc.16.37

• subjected to X-ray crystallographic analysis. Orange single crystals were formed by the diffusion of pentane vapor to a 1,1,1-trichloroethane solution of 1 synthesized by the C–H borylation method. The crystal structure confirmed that the C–H borylation proceeded regioselectively at the least hindered C–H

Synthesis and circularly polarized luminescence properties of BINOL-derived bisbenzofuro[2,3-b:3’,2’-e]pyridines (BBZFPys)

• Ryo Takishima,
• Yuji Nishii,
• Tomoaki Hinoue,
• Yoshitane Imai and
• Masahiro Miura

Beilstein J. Org. Chem. 2020, 16, 325–336, doi:10.3762/bjoc.16.32

• /EtOAc 4:1) and GPC to give the title compound as pale yellow solid; (S)-4c (74.1 mg, 29% yield), (R)-4c (90.0 mg, 36% yield). Single crystals suitable for the X-ray analysis were obtained by hexane vapor diffusion into CHCl3 solution. Mp >300 °C; 1H NMR (400 MHz, CDCl3) δ 1.41 (s, 18H), 1.45 (s, 18H

Absolute configurations of talaromycones A and B, α-diversonolic ester, and aspergillusone B from endophytic Talaromyces sp. ECN211

• Ken-ichi Nakashima,
• Junko Tomida,
• Takao Hirai,
• Yoshiaki Kawamura and
• Makoto Inoue

Beilstein J. Org. Chem. 2020, 16, 290–296, doi:10.3762/bjoc.16.28

• carbonyl group at the C-7 position. However, the complete structure of 1 could not be determined by NMR spectroscopy due to a lack of HMBC correlations between the partial structures. Therefore, we crystalized 1 by vapor diffusion with benzene/n-hexane. Single-crystal X-ray diffraction using Cu radiation

• in good agreement with those of 1 (Figure 3b), the absolute configuration of 2 was also assigned to be R. Single crystals of α-diversonolic ester (3) were obtained as colorless prisms by vapor diffusion with acetone/n-hexane, and single-crystal X-ray diffractometry determined the structure shown in

The use of isoxazoline and isoxazole scaffolding in the design of novel thiourea and amide liquid-crystalline compounds

• Itamar L. Gonçalves,
• Rafaela R. da Rosa,
• Vera L. Eifler-Lima and
• Aloir A. Merlo

Beilstein J. Org. Chem. 2020, 16, 175–184, doi:10.3762/bjoc.16.20

• (18a, 18c and 20), confirming that a longitudinal diffusion is favored for this type of LC compounds [19]. For the amides an SmA mesophase was found in 19, 20, 22 and 24. The liquid crystal mesophase ranges for these amides are dependent on the 5-membered ring connecting the aryl groups. Thus, 19 and

• , isoxazoline derivatives induce the formation of an SmA mesophase by lateral diffusion, while isoxazole derivatives favor the formation of a nematic mesophase by longitudinal diffusion, along SmA mesophase [27]. In addition, for amide 19, a second smectic mesophase was identified by POM as the monotropic SmC

Halogen-bonding-induced diverse aggregation of 4,5-diiodo-1,2,3-triazolium salts with different anions

• Xingyu Xu,
• Shiqing Huang,
• Zengyu Zhang,
• Lei Cao and
• Xiaoyu Yan

Beilstein J. Org. Chem. 2020, 16, 78–87, doi:10.3762/bjoc.16.10

• good yield (Scheme 1). The product 2-I was characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometry. 2-I has a poor solubility in most organic solvents such as dichloromethane, trichloromethane, tetrahydrofuran, and ethanol. A single crystal of 2-I was obtained by slow diffusion of ether

• into dimethylformamide solution. Ion exchange of 2-I with AgBF4 afforded 2-BF4. In contrast, 2-BF4 was soluble in dichloromethane and trichloromethane. A single crystal of 2-BF4 was obtained by slow diffusion of ether into a dichloromethane solution. In a similar manner, 2-OAc and 2-TFA were obtained

• via removing the iodide anion by AgOAc and CF3COOAg. A single crystal of 2-OAc suitable for X-ray diffraction analysis was obtained by slow diffusion of n-pentane into a dichloromethane solution. A single crystal of 2-TFA suitable for X-ray diffraction analysis was obtained by slow evaporation of

A chiral self-sorting photoresponsive coordination cage based on overcrowded alkenes

• Constantin Stuckhardt,
• Diederik Roke,
• Wojciech Danowski,
• Edwin Otten,
• Sander J. Wezenberg and
• Ben L. Feringa

Beilstein J. Org. Chem. 2019, 15, 2767–2773, doi:10.3762/bjoc.15.268

• Supporting Information File 1, section 2). The measured diffusion coefficients (D = 8.7 × 10−10 m2 s−1 for Pd2(stable Z-1)4 and D = 7.9 × 10−10 m2 s−1 for cage Pd2(stable E-1)4 in CD3CN at 23 °C) can be translated into hydrodynamic radii of rH = 7.2 Å for Pd2(stable Z-1)4 and rH = 8.0 Å for Pd2(stable E-1)4

• crystal of Pd2(stable E-1)4 formed from a racemic mixture of ligand E-1 suitable for X-ray structure determination was grown by vapor diffusion of a 1:1 mixture of benzene and diethyl ether into a solution of the cage in a 1:1 mixture of acetonitrile and chloroform. The crystal structure shows cage

Probing of local polarity in poly(methyl methacrylate) with the charge transfer transition in Nile red

• Aydan Yadigarli,
• Qimeng Song,
• Sergey I. Druzhinin and
• Holger Schönherr

Beilstein J. Org. Chem. 2019, 15, 2552–2562, doi:10.3762/bjoc.15.248

• substrate-supported ultrathin films [13], the analysis of the photophysical properties of tracer dye molecules was found to be beneficial. In time-resolved fluorescence measurements and dye diffusion studies, the nanoenvironments in polymersomes could be assigned [1][12], solute transport be characterized

Self-assembled coordination thioether silver(I) macrocyclic complexes for homogeneous catalysis

• Zhen Cao,
• Aline Lacoudre,
• Cybille Rossy and
• Brigitte Bibal

Beilstein J. Org. Chem. 2019, 15, 2465–2472, doi:10.3762/bjoc.15.239

• for 1a, AgOTFA for 1b, AgNO3 for 1c and PPh3AgOTf for 1d. Crystallographic structures of silver complexes Single crystals of 1a, 1c and 1d suitable for X-ray diffraction analysis were grown from the slow diffusion of hexane into a solution of each complex in dichloromethane. Interestingly, each

• different 1H NMR spectra may account for the existence of several conformations for these constrained coordinated architectures, which still have a certain degree of freedom, that is required for further catalytic properties. Diffusion-ordered spectroscopy (DOSY) 1H NMR was also used on complexes 1a–d (5 mM

• ) in CDCl3 (Supporting Information File 1, Table S7). Each complex appeared as a unique species whose diffusion coefficient (D) can be fitted. So the presence of species with different coordination modes can be excluded. Unexpectedly, the diffusion constants of both complexes 1a and 1b were disparate

Photochromic diarylethene ligands featuring 2-(imidazol-2-yl)pyridine coordination site and their iron(II) complexes

• Andrey G. Lvov,
• Max Mörtel,
• Anton V. Yadykov,
• Frank W. Heinemann,
• Valerii Z. Shirinian and
• Marat M. Khusniyarov

Beilstein J. Org. Chem. 2019, 15, 2428–2437, doi:10.3762/bjoc.15.235

• . Crystals suitable for X-ray structure were obtained in a fritted U-shape tube by the slow diffusion of methanol solutions of in situ-prepared “Fe(H2B(pz)2)2“ and diarylethene 6. Unexpectedly, we have found that the structure of the product depends on the reaction time. Reproducible crystals isolated after

Reversible switching of arylazopyrazole within a metal–organic cage

• Anton I. Hanopolskyi,
• Soumen De,
• Michał J. Białek,
• Yael Diskin-Posner,
• Liat Avram,
• Moran Feller and
• Rafal Klajn

Beilstein J. Org. Chem. 2019, 15, 2398–2407, doi:10.3762/bjoc.15.232

• )22 prior to UV irradiation and, as expected, did not observe any shifts of 1’s signals. To further confirm the photoswitching-induced guest expulsion, we performed detailed diffusion-ordered spectroscopy (DOSY) measurements. A representative DOSY spectrum of (E-1)22 is shown in Figure 7, left. The

• spectrum indicates the presence of a single species (the diffusion coefficient for 1, D1 = 1.91 (±0.01) · 10−10 m2·s−1 (based on averaging Ha and Hd); the diffusion coefficient for 2, D2 = 1.85 (±0.01) · 10−10 m2·s−1 (based on H4); each diffusion measurement was repeated three times). In contrast, DOSY

• spectra recorded after UV irradiation exhibited two distinct sets of diffusion coefficients, associated with resonances of 1 and 2 (red and green shades in Figure 7, center). The average diffusion coefficients were determined as D1 = 3.44 (±0.04) · 10−10 m2·s−1 and D2 = 1.86 (±0.01) · 10−10 m2·s−1. The

Synthesis of a dihalogenated pyridinyl silicon rhodamine for mitochondrial imaging by a halogen dance rearrangement

• Jessica Matthias,
• Thines Kanagasundaram,
• Klaus Kopka and
• Carsten S. Kramer

Beilstein J. Org. Chem. 2019, 15, 2333–2343, doi:10.3762/bjoc.15.226

• . Lipophilic cations such as the phosphonium cation or rhodamines are known to accumulate selectively within the mitochondria, driven by the mitochondrial plasma membrane potential [39][40]. Thereby, the high lipophilicity facilitates the diffusion through the lipid bilayers of the cell and mitochondrial

Isolation of fungi using the diffusion chamber device FIND technology

• Benjamin Libor,
• Henrik Harms,
• Stefan Kehraus,
• Ekaterina Egereva,
• Max Crüsemann and
• Gabriele M. König

Beilstein J. Org. Chem. 2019, 15, 2191–2203, doi:10.3762/bjoc.15.216

• contamination by other microbes. These membranes, at the same time, permit diffusion of nutrients and growth factors from the environment through the feeding pores of the upper and lower plates. This way slow growing fungi or to date uncultured fungi can be isolated. To test the FIND technology, we used samples

• other 10 isolates grown on BMS medium were tested in disk diffusion assays using 50 µg of extract per disk. None of the extracts was active against the Gram-negative bacterium E. coli. Extracts of A. armoraciae, Auxarthron umbrinum, C. globosum, Chrysosporium sp. 831, C. allicinum, C. rosea, H. cf

• (Leica, Wetzlar, Germany) and micromorphology was examined with an Olympus BX51 polarizing microscope (Olympus, Shinjuku, Japan) by analysis of conidia and mycelium to support the bioinformatic suggestions. Fermentation, extraction and isolation For cultivation of the marine isolates from the diffusion

Multiple threading of a triple-calix[6]arene host

• Veronica Iuliano,
• Roberta Ciao,
• Emanuele Vignola,
• Carmen Talotta,
• Patrizia Iannece,
• Margherita De Rosa,
• Annunziata Soriente,
• Carmine Gaeta and
• Placido Neri

Beilstein J. Org. Chem. 2019, 15, 2092–2104, doi:10.3762/bjoc.15.207

• diffusion coefficient of 7.06 × 10−11 m2/s attributable to the 7+6 pseudo[2]rotaxane as TFPB− salt and significantly lower than that measured for the free triple-calix[6]arene host 6 of 3.02 × 10–10 m2/s. Through an 1H NMR quantitative analysis of a 1:1 mixture of 7+·TFPB– and 6 in CDCl3, using 1,1,2,2

Synthesis and anion binding properties of phthalimide-containing corona[6]arenes

• Meng-Di Gu,
• Yao Lu and
• Mei-Xiang Wang

Beilstein J. Org. Chem. 2019, 15, 1976–1983, doi:10.3762/bjoc.15.193

• -corona[6]arenes in the solid state, high quality single crystals of 3a were grown at room temperature from diffusion of diethyl ether vapor into the solution of 3a in acetonitrile. X-ray diffraction analysis revealed that the macrocycle 3a adopted an interesting conformation. As depicted in Figure 1, it

• ability of 3a to bind various anion species in gas phase. To our delight, host molecule 3a co-crystalized with n-Bu4NX (X = Cl, Br) from diffusion of diethyl ether vapor into ethyl acetate solution at ambient temperature to give single crystals of the host–guest complexes (n-Bu4NX)3-3a (X = Cl, Br). X-ray

Complexation of chiral amines by resorcin[4]arene sulfonic acids in polar media – circular dichroism and diffusion studies of chirality transfer and solvent dependence

• Bartosz Setner and
• Agnieszka Szumna

Beilstein J. Org. Chem. 2019, 15, 1913–1924, doi:10.3762/bjoc.15.187

• (ArgOMe)2 that may come from the differences in stability of the complexes. This qualitative observation is supported by DOSY measurements (Figure 4) [24]. DOSY measurements indicate that for [1(LysOMe)2]MeOH the two components of the complex exhibit noticeably different diffusion coefficients (D) with a

• lower value for 1 (3.6 × 10−10 m2 s−1, methanol-d4, 298 K) and slightly higher value for LysOMe (4.0 × 10−10 m2 s−1, methanol-d4, 298 K). This suggests that under such conditions [1(LysOMe)2]MeOH partially dissociates and the LysOMe component exhibits a diffusion coefficient that has a dynamically

• averaged value between complex 1(LysOMe)2 and free LysOMe. This interpretation is supported by an experiment with an excess of LysOMe (Figure 4e). In [LysOMe + 1(LysOMe)2]MeOH mixture the diffusion coefficient for the LysOMe component exhibits a considerably higher value than in [1(LysOMe)2]MeOH that

Norbornadiene-functionalized triazatriangulenium and trioxatriangulenium platforms

• Roland Löw,
• Talina Rusch,
• Tobias Moje,
• Fynn Röhricht,
• Olaf M. Magnussen and
• Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 1815–1821, doi:10.3762/bjoc.15.175

• smaller size of 6 and its correspondingly higher diffusion coefficient, which results in faster transport to the Au surface and accordingly enhanced surface coverages. Thus, even low decay rates of 1a may lead to sufficiently high concentrations of 6 for obtaining mixed adlayers. By varying the

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

• complex H1·G1 was obtained by vapor diffusion of isopropyl ether into acetone. As shown in Figure 4, G1 was encapsulated in the cavity of H1 to form a 1:1 complex, in which G1 is distorted by the dihedral angle between the pyridinium rings of 33.19°. There exist multiple CH···π interactions between the

• diffusion of isopropyl ether into a chloroform/acetone 1:1 (v/v) solution of the 1:1 mixture of H3 and G1, we only obtained a single crystal of H3 instead of the host–guest complex. The steric hindrance of the n-butoxy groups in H3 (Supporting Information File 1, Figure S90) might lead to weak complexation

• of H3 with the tested guests in solution. However, we obtained a single crystal of complex H5·G1 by vapor diffusion of isopropyl ether into an acetone solution. As shown in Figure 5, we found that G1 was encapsulated in the cavity of H5 to form a 1:1 complex, and the complex molecules are stacked