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Search for "π-stacking" in Full Text gives 207 result(s) in Beilstein Journal of Organic Chemistry. Showing first 200.

Efficient synthesis of pyrazolopyridines containing a chromane backbone through domino reaction

  • Razieh Navari,
  • Saeed Balalaie,
  • Saber Mehrparvar,
  • Fatemeh Darvish,
  • Frank Rominger,
  • Fatima Hamdan and
  • Sattar Mirzaie

Beilstein J. Org. Chem. 2019, 15, 874–880, doi:10.3762/bjoc.15.85

Graphical Abstract
  • of the product (Figure 2). Meanwhile, via hydrogen bridges and the solvent molecules (water and ethanol) the molecules build pairs with π–π stacking of the aromatic systems. To examine the scope and generality of our reaction, other (arylhydrazono)methyl-4H-chromen-4-ones were synthesized and their
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Published 11 Apr 2019

Coordination chemistry and photoswitching of dinuclear macrocyclic cadmium-, nickel-, and zinc complexes containing azobenzene carboxylato co-ligands

  • Jennifer Klose,
  • Tobias Severin,
  • Peter Hahn,
  • Alexander Jeremies,
  • Jens Bergmann,
  • Daniel Fuhrmann,
  • Jan Griebel,
  • Bernd Abel and
  • Berthold Kersting

Beilstein J. Org. Chem. 2019, 15, 840–851, doi:10.3762/bjoc.15.81

Graphical Abstract
  • lengths reveal no anomalies and are similar to those in [Zn2L(μ-OAc)]+. There are no π–π stacking interactions between the azobenzene moieties. However, the [Zn2L(μ-azo-OH)]+ and [Zn2L(μ-azo-O)] complexes are connected by a OH···O hydrogen bond of length 2.46 Å (O3a···O3b, not shown in Figure 4). [Zn2L(μ
  • , respectively. These values compare well with those in 3' and other [Zn2L(μ-carboxylato)]+ complexes. The [Zn2L(μ-azo-NMe2)]+ complexes in 5 assemble in pairs (Figure 5) most likely via π···π stacking interactions, as manifested by the distance of 3.34 Å between the planes through the azobenzene moieties. [Cd2L
  • radius of Cd2+. The Cd···Cd distance is at 3.399 Å. Virtually the same values are observed in [Cd2L(μ-OAc)]+ [10]. As in 5 π–π stacking of the azo-carboxylato co-ligands occurs (Figure 7). The shortest distance between two carbon atoms of adjacent benzene rings is at 3.41 Å. [Ni2L(μ-Azo-NMe2)]ClO4·xEtOH
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Published 03 Apr 2019

Synthesis of functionalized diazocines for application as building blocks in photo- and mechanoresponsive materials

  • Widukind Moormann,
  • Daniel Langbehn and
  • Rainer Herges

Beilstein J. Org. Chem. 2019, 15, 727–732, doi:10.3762/bjoc.15.68

Graphical Abstract
  • functionalized compounds are rare [19][20][21][22][23]. In contrary to azobenzenes, diazocines 1 are stable in their cis configuration. The bent cis isomer is less prone to π–π stacking which is known to reduce the switching efficiency (Figure 1a) [19][24]. The reverse stability of the cis and trans isomers in
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Published 20 Mar 2019

Targeting the Pseudomonas quinolone signal quorum sensing system for the discovery of novel anti-infective pathoblockers

  • Christian Schütz and
  • Martin Empting

Beilstein J. Org. Chem. 2018, 14, 2627–2645, doi:10.3762/bjoc.14.241

Graphical Abstract
  • (His71) sidechain via π-stacking. For the thiophene-containing fragment 26 a π–π interaction of the sulfur with Phe195 can be observed. In vitro evaluation was performed using a combined PqsDE assay due to the aforementioned instability of 2-ABA-CoA which in this scenario is generated in situ from
  • protein [79]. Indicated key interactions are π-stacking of Y258 with the phenoxy moiety in the tail region and a hydrogen bond formed between the Q194 side chain and the carboxamide in the linker area. Furthermore the benzimidazole core shows hydrophobic contacts with isoleucins 149 and 236. More
  • Y258M P. aeruginosa mutant strain. The importance of the phenoxy substitutent was further supported by a congener of M64 that lacks this motif and therefore is unable to be involved in π-stacking resulting in a nine-fold increased IC50 value compared to M64. Even though there is no specific interaction
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Published 15 Oct 2018

Evaluation of dispersion type metal···π arene interaction in arylbismuth compounds – an experimental and theoretical study

  • Ana-Maria Preda,
  • Małgorzata Krasowska,
  • Lydia Wrobel,
  • Philipp Kitschke,
  • Phil C. Andrews,
  • Jonathan G. MacLellan,
  • Lutz Mertens,
  • Marcus Korb,
  • Tobias Rüffer,
  • Heinrich Lang,
  • Alexander A. Auer and
  • Michael Mehring

Beilstein J. Org. Chem. 2018, 14, 2125–2145, doi:10.3762/bjoc.14.187

Graphical Abstract
  • Grimme [54] and Iverson et al. [55] on the unreflected use of terms such as C–H···π, or π···π stacking previously. In most cases, these interactions rely on London dispersion forces rather than special types of bonding due to the π system. Crystal structures In all of the presented compounds, the
  • ···π arene type dimers and selected π-stacking dimers were computed at the DLPNO-CCSD(T)/cc-pVQZ (cc-pwCVQZ-PP for Bi) level of theory with TightPNO settings (see Figures 12, 14, and 16). Local energy decomposition analysis was performed in order to obtain the dispersion energy contributions to the
  • interaction energies. The dispersion energies of the specific dimers were then visualized as DED plots and are shown in Figures 12, 14, and 16. The structures and interaction energies of all studied π-stacking dimers are given in Supporting Information File 1 (see Figures S12–S14 and Table S4 in Supporting
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Published 15 Aug 2018

Functionalization of graphene: does the organic chemistry matter?

  • Artur Kasprzak,
  • Agnieszka Zuchowska and
  • Magdalena Poplawska

Beilstein J. Org. Chem. 2018, 14, 2018–2026, doi:10.3762/bjoc.14.177

Graphical Abstract
  • , was assigned to the stretching vibrations of the alkyl chain (commonly observed at up to 2980 cm−1); this absorption band corresponds to the N–H stretching vibrations of NH3+. The further reaction with amphotericin B, which is a compound containing unsaturated bonds, was most plausibly a result of π–π
  • stacking. As mentioned above in the discussion of reaction mechanisms, water molecules significantly lower the reaction rates for the desired nucleophiles. Importantly, water molecules also influence the hydrolysis of the activated carboxyl groups (Figure 2, step d and Figure 3, step f). Water should
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Published 02 Aug 2018

A self-assembled photoresponsive gel consisting of chiral nanofibers

  • Lei Zou,
  • Dan Han,
  • Zhiyi Yuan,
  • Dongdong Chang and
  • Xiang Ma

Beilstein J. Org. Chem. 2018, 14, 1994–2001, doi:10.3762/bjoc.14.174

Graphical Abstract
  • by three-dimensional networks through self-assembly have drawn significant attention in the past decades. They are normally fabricated by means of noncovalent intermolecular interactions [3], such as π–π stacking, hydrogen bonding, van der Waals forces, hydrophobic, electrostatic, host–guest and
  • construct optically controlled systems [17][30][32][33][34][35]. This moiety is also frequently employed as a building block because of its strong π–π stacking in nonpolar solvents. Herein, a novel compound 3 containing both chiral L-glutamic lipid and azobenzene was designed and synthesized (Scheme 1). It
  • and π–π stacking in DMSO. However, beautiful acicular fibers could be detected on the surface treated with a chloroform solution, and a dendritic network was observed on the sample made from benzene solution (Figure S9, Supporting Information File 1). The photoresponsiveness of compound 3 was also
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Published 01 Aug 2018

Synthesis of new p-tert-butylcalix[4]arene-based polyammonium triazolyl amphiphiles and their binding with nucleoside phosphates

  • Vladimir A. Burilov,
  • Guzaliya A. Fatikhova,
  • Mariya N. Dokuchaeva,
  • Ramil I. Nugmanov,
  • Diana A. Mironova,
  • Pavel V. Dorovatovskii,
  • Victor N. Khrustalev,
  • Svetlana E. Solovieva and
  • Igor S. Antipin

Beilstein J. Org. Chem. 2018, 14, 1980–1993, doi:10.3762/bjoc.14.173

Graphical Abstract
  • nucleotides must possess selectivity towards these anions. From this point of view, nucleotide receptors based on polyammonium cations are of great demand because the electrostatic interactions of such polyammonium systems and negatively charged phosphates are strong. Hydrogen bonding [8] and π-stacking
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Published 31 Jul 2018

A pyridinium/anilinium [2]catenane that operates as an acid–base driven optical switch

  • Sarah J. Vella and
  • Stephen J. Loeb

Beilstein J. Org. Chem. 2018, 14, 1908–1916, doi:10.3762/bjoc.14.165

Graphical Abstract
  • the crown ether. In addition, π-stacking interactions induce upfield shifts for protons p, q, v and w from 8.48 ppm in 74+ to 8.24 ppm for [8DB24C8]6+. Protons o, x, n and y do not shift appreciably because the crown ether does not extend far enough to interact with these protons. In contrast, the
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Published 25 Jul 2018

Synthesis of 9-arylalkynyl- and 9-aryl-substituted benzo[b]quinolizinium derivatives by Palladium-mediated cross-coupling reactions

  • Siva Sankar Murthy Bandaru,
  • Darinka Dzubiel,
  • Heiko Ihmels,
  • Mohebodin Karbasiyoun,
  • Mohamed M. A. Mahmoud and
  • Carola Schulzke

Beilstein J. Org. Chem. 2018, 14, 1871–1884, doi:10.3762/bjoc.14.161

Graphical Abstract
  • quadruplex DNA, the derivatives 2a–d show a typical titration signature for ligands that bind to the quadruplex by terminal π-stacking [14]; however, in analogy to the binding to duplex DNA the derivatives 2b–d form aggregates along the DNA backbone at large ligand–DNA ratio, i.e., at the beginning of the
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Published 23 Jul 2018

Efficient catenane synthesis by cucurbit[6]uril-mediated azide–alkyne cycloaddition

  • Antony Wing Hung Ng,
  • Chi-Chung Yee,
  • Kai Wang and
  • Ho Yu Au-Yeung

Beilstein J. Org. Chem. 2018, 14, 1846–1853, doi:10.3762/bjoc.14.158

Graphical Abstract
  • –ligand coordination, charge transfer, π-stacking and hydrophobic interactions, for the later interlocking of additional macrocycles to give higher-order [n]catenanes. The new building blocks were synthesized following similar procedures as previously described [24]. Catenane synthesis by CBAAC Synthesis
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Published 20 Jul 2018

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

Graphical Abstract
  • previously reported nanosystems as polymeric nanoparticles. In covalent series, G-1 dendron D-N

    NH itself (as unexpected reference) self-assembled into nanospheres with a high D value (694 nm). We ascribed this packing ability to three basic π stacking interactions [72] associating stratified parallel

  • , 8 and 9; the red arrow indicates the nano-particles that aggregate. D is the average diameter of nanospheres. Proposed π-stacking interactions in compounds D-N

    NH and 5–7a. Convergent versus divergent three steps (a–c) synthesis of central building blocks C1 and C3. Synthesis of G-1 dendrons D-Cl

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Published 09 Jul 2018

Steric “attraction”: not by dispersion alone

  • Ganna Gryn’ova and
  • Clémence Corminboeuf

Beilstein J. Org. Chem. 2018, 14, 1482–1490, doi:10.3762/bjoc.14.125

Graphical Abstract
  • cages [10]. Intermolecular interactions in hydrocarbons are also subject to significant dispersion contribution. In the unsaturated systems, from benzene dimer to higher acenes and, ultimately, graphenes, dispersion is increasingly the key force behind the π–π stacking interactions [11]. Large and flat
  • electrostatic contribution to it [25]. For example, “dispersion dominates and electrostatics commands” is the ‘punch line’ of the 2017 computational study on the σ–σ, σ–π and π–π stacking interactions between benzene, cyclohexane and some of their fluorinated derivatives [26]. The authors show that while
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Published 19 Jun 2018

Recent advances in phosphorescent platinum complexes for organic light-emitting diodes

  • Cristina Cebrián and
  • Matteo Mauro

Beilstein J. Org. Chem. 2018, 14, 1459–1481, doi:10.3762/bjoc.14.124

Graphical Abstract
  • including formation of metallophilic d8···d8 interactions and/or π–π stacking of the coordinating ligands [67][92] as well as excited-state interactions such as formation of excimers [93][94]. Although they may be usefully employed to shift both absorption and emission spectra
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Published 18 Jun 2018

Enantioselective phase-transfer catalyzed alkylation of 1-methyl-7-methoxy-2-tetralone: an effective route to dezocine

  • Ruipeng Li,
  • Zhenren Liu,
  • Liang Chen,
  • Jing Pan and
  • Weicheng Zhou

Beilstein J. Org. Chem. 2018, 14, 1421–1427, doi:10.3762/bjoc.14.119

Graphical Abstract
  • , then two additional interaction forces in the complex are produced on the same plane, including: 1) the carbonyl of 2 makes a hydrogen bond with the hydroxy group of C7; 2) the phenyl group of 2 forms a face-to-face π-stacking interaction with the benzyl moiety of C7. The complex of 2 with C7 goes to
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Published 11 Jun 2018

Are dispersion corrections accurate outside equilibrium? A case study on benzene

  • Tim Gould,
  • Erin R. Johnson and
  • Sherif Abdulkader Tawfik

Beilstein J. Org. Chem. 2018, 14, 1181–1191, doi:10.3762/bjoc.14.99

Graphical Abstract
  • been increasing interest in utilizing non-covalent π-stacking for synthetic catalysis – and it is notable that most structures shown in a recent review on the topic feature rings that interact at distances greater than the potential minimum [26]. Benzene dimers also feature in the S22 benchmark set [21
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Published 23 May 2018

An overview of recent advances in duplex DNA recognition by small molecules

  • Sayantan Bhaduri,
  • Nihar Ranjan and
  • Dev P. Arya

Beilstein J. Org. Chem. 2018, 14, 1051–1086, doi:10.3762/bjoc.14.93

Graphical Abstract
  • heterocyclic rings such as furan 62 and 63 [126], thiophene 64 [127] and pyridine 65 (Figure 11) [128]. These conjugates exhibit potent antibacterial and antiprotozoal activity with much reduced toxicity. It was further concluded that π-stacking, H-bonding with the floor of the minor groove along with
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Published 16 May 2018

An uracil-linked hydroxyflavone probe for the recognition of ATP

  • Márton Bojtár,
  • Péter Zoltán Janzsó-Berend,
  • Dávid Mester,
  • Dóra Hessz,
  • Mihály Kállay,
  • Miklós Kubinyi and
  • István Bitter

Beilstein J. Org. Chem. 2018, 14, 747–755, doi:10.3762/bjoc.14.63

Graphical Abstract
  • recognition sites [16][18][19][33], or Zn-dipicolylamine complexes [21][23][24] attracting the negatively charged phosphate units of ATP and by π-stacking between the fluorophores of the sensors and the adenine moiety of ATP [29]. In aqueous solutions at physiological pH, the tetra-charged anionic ATP
  • , 4’-dimethylaminohydroxyflavone) was utilized by Pivovarenko and co-workers in ATP sensing in aqueous solution and in mitochondria [34][44]. DMHF was found to form 1:1 and 1:2 complexes with ATP. The two components were held together by π-stacking and by electrostatic interactions of the positively
  • [45], however, none of them are the result of rational design. Base pairing is a well-known phenomenon in the double helix structure of DNA since the work of Watson and Crick. It is also known that the cohesion of the double strand is provided by the efficient π-stacking interaction [46]. Adding
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Published 03 Apr 2018

Recent advances on organic blue thermally activated delayed fluorescence (TADF) emitters for organic light-emitting diodes (OLEDs)

  • Thanh-Tuân Bui,
  • Fabrice Goubard,
  • Malika Ibrahim-Ouali,
  • Didier Gigmes and
  • Frédéric Dumur

Beilstein J. Org. Chem. 2018, 14, 282–308, doi:10.3762/bjoc.14.18

Graphical Abstract
  • luminance of 100 cd/m2, slightly red-shifted compared to the emission observed for doped OLEDs. Clearly, the specific design of D6 and its highly twisted structure efficiently weakened the π–π-stacking interactions, providing a general design rule for the elaboration of TADF emitters insensitive to the
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Published 30 Jan 2018

Fluorogenic PNA probes

  • Tirayut Vilaivan

Beilstein J. Org. Chem. 2018, 14, 253–281, doi:10.3762/bjoc.14.17

Graphical Abstract
  • of the TO label to DNA or RNA duplexes were occasionally observed, this could be suppressed by using a shorter linker (as in FIT PNA probes, vide infra) or by combination with a second dye, such as pyrene, that can interact with TO by π-stacking. Such a combination in a short PNA probe has been used
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Published 29 Jan 2018

Synthesis and supramolecular properties of regioisomers of mononaphthylallyl derivatives of γ-cyclodextrin

  • Markéta Bláhová,
  • Sergey K. Filippov,
  • Lubomír Kováčik,
  • Jiří Horský,
  • Simona Hybelbauerová,
  • Zdenka Syrová,
  • Tomáš Křížek and
  • Jindřich Jindřich

Beilstein J. Org. Chem. 2017, 13, 2509–2520, doi:10.3762/bjoc.13.248

Graphical Abstract
  • the shape of peaks, but also in the value of the chemical shifts. For both regioisomers the concentration dependence of chemical shifts in aromatic and allyl areas indicates intermolecular association such as inclusion of the naphthylallyl moiety into the cavity of γ-CD or π stacking of naphthyls. The
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Published 27 Nov 2017

One-pot syntheses of blue-luminescent 4-aryl-1H-benzo[f]isoindole-1,3(2H)-diones by T3P® activation of 3-arylpropiolic acids

  • Melanie Denißen,
  • Alexander Kraus,
  • Guido J. Reiss and
  • Thomas J. J. Müller

Beilstein J. Org. Chem. 2017, 13, 2340–2351, doi:10.3762/bjoc.13.231

Graphical Abstract
  • 5 (left) and a centrosymmetric dimer formation by π–π interactions (right) (ellipsoids are drawn at the 40% probability level). The ORTEP-type plot of the asymmetric unit of the crystal structure 6 (top) and π-stacking interactions (bottom) (ellipsoids are drawn at the 40% probability level
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Published 03 Nov 2017

Complexation of molecular clips containing fragments of diphenylglycoluril and benzocrown ethers with paraquat and its derivatives

  • Leonid S. Kikot',
  • Catherine Yu. Kulygina,
  • Alexander Yu. Lyapunov,
  • Svetlana V. Shishkina,
  • Roman I. Zubatyuk,
  • Tatiana Yu. Bogaschenko and
  • Tatiana I. Kirichenko

Beilstein J. Org. Chem. 2017, 13, 2056–2067, doi:10.3762/bjoc.13.203

Graphical Abstract
  • π–π stacking and C–H∙∙∙X (X = N, O, F ...) interactions. The stability of inclusion complexes based on molecular clips and paraquat derivatives depends on two factors: 1) the value of the positive charge on the dipyridinium fragment of paraquat derivatives, the distribution of which is well
  • paraquat, the following moieties may be involved: the glycoluril fragment (hydrogen bonds involving the oxygen atoms of the carbonyl groups), the catechol part of the crown ether fragments (π–π stacking interactions) and the polyether chains of benzocrown ethers (C–H···О interactions). The first two
  • complexation constant of the clip 6 with paraquat (7), which was: lgK = 1.46 ± 0.01 (−ΔG = 1.96 ± 0.02 kcal/mol). The complex of clip 6 with paraquat (7) may be stabilized through π–π stacking interactions of the electron-deficient aromatic rings of paraquat and the electron donating veratrol fragments of the
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Published 04 Oct 2017

Mechanochemical synthesis of small organic molecules

  • Tapas Kumar Achar,
  • Anima Bose and
  • Prasenjit Mal

Beilstein J. Org. Chem. 2017, 13, 1907–1931, doi:10.3762/bjoc.13.186

Graphical Abstract
  • solvent-free mechanomilling [50]. By varying the electron density on the aromatic aldehydes, it was observed that electron deficient aldehydes provided a better yield with excellent stereo selectivity over electron rich systems. The observed result suggests that a π–π stacking interaction between electron
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Published 11 Sep 2017

Sugar-based micro/mesoporous hypercross-linked polymers with in situ embedded silver nanoparticles for catalytic reduction

  • Qing Yin,
  • Qi Chen,
  • Li-Can Lu and
  • Bao-Hang Han

Beilstein J. Org. Chem. 2017, 13, 1212–1221, doi:10.3762/bjoc.13.120

Graphical Abstract
  • described as the Langmuir–Freundlich isotherm [47]. The polymer matrix has higher adsorption capacity for 4-NP due to π–π stacking interactions, which can encourage 4-NP molecules to enter the polymer channel to form the adsorbed species [54]. At the same time, the hydrogen atom is introduced onto the
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Published 22 Jun 2017
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