Binding mode and free energy prediction of fisetin/β-cyclodextrin inclusion complexes

• Bodee Nutho,
• Wasinee Khuntawee,
• Chompoonut Rungnim,
• Piamsook Pongsawasdi,
• Peter Wolschann,
• Alfred Karpfen,
• Nawee Kungwan and
• Thanyada Rungrotmongkol

Beilstein J. Org. Chem. 2014, 10, 2789–2799, doi:10.3762/bjoc.10.296

• definition of the A- and B-rings (chromone and phenyl subunits). The atomic labels and the torsional angle (τ) between both aromatic rings are given. (A) Chemical structure of β-CD and (B) its truncated cone shape. Docked structures of the four possible inclusion complexes between fisetin and β-CD, where

Synthesis of nanodiamond derivatives carrying amino functions and quantification by a modified Kaiser test

• Gerald Jarre,
• Steffen Heyer,
• Elisabeth Memmel,
• Thomas Meinhardt and
• Anke Krueger

Beilstein J. Org. Chem. 2014, 10, 2729–2737, doi:10.3762/bjoc.10.288

• 0.15 mmol g−1 for the Diels–Alder reaction of the non-functionalized ortho-quinodimethane [11] proves that a significantly increased grafting is observed using the pyrazine derivative. So far, the reported cycloaddition reactions of ortho-quinodimethanes leading to the grafting of aromatic rings by

Cyclodextrin-grafted polymers functionalized with phosphanes: a new tool for aqueous organometallic catalysis

• Jonathan Potier,
• Stéphane Menuel,
• David Mathiron,
• Véronique Bonnet,
• Frédéric Hapiot and
• Eric Monflier

Beilstein J. Org. Chem. 2014, 10, 2642–2648, doi:10.3762/bjoc.10.276

• isolated in 55% yield as white crystals. The meta-sulfonation on the aromatic rings was confirmed by NMR. The COSY spectrum (Supporting Information File 1) was especially indicative of the meta-substitution. Indeed, H4 (Scheme 1) did not correlate with any other proton and appeared as an upfield shifted

Selenium halide-induced bridge formation in [2.2]paracyclophanes

• Laura G. Sarbu,
• Henning Hopf,
• Peter G. Jones and
• Lucian M. Birsa

Beilstein J. Org. Chem. 2014, 10, 2550–2555, doi:10.3762/bjoc.10.266

• neglected so far. Functional groups in pseudo-geminally substituted [2.2]paracyclophanes often undergo highly specific reactions. This is due to the rigid framework and the short distance between the two aromatic rings within the [2.2]paracyclophane unit. Thus, unsaturated cyclophane bis(esters) undergo

New highlights of the syntheses of pyrrolo[1,2-a]quinoxalin-4-ones

• Emilian Georgescu,
• Alina Nicolescu,
• Florentina Georgescu,
• Florina Teodorescu,
• Daniela Marinescu,
• Ana-Maria Macsim and
• Calin Deleanu

Beilstein J. Org. Chem. 2014, 10, 2377–2387, doi:10.3762/bjoc.10.248

• , quartet, 7.2 Hz, CH2), 5.50 (2H, bs, CH2), 7.19–7.33 (8H, m, aromatic rings), 7.68 (1H, d, 1.6 Hz, H-3), 7.72–7.73 (1H, m, H-9), 8.24 (1H, d, 1.6 Hz, H-1). The individual chemical shifts, multiplicities and coupling constants for the 7.19–7.33 multiplet were obtained from undecoupled HSQC as follows: 7.21

• Hz, CH2-3), 4.45 (2H, quartet, 7.2 Hz, CH2-1), 6.13 (2H, bs, CH2), 7.25–7.32 (8H, m, aromatic rings), 7.78 (1H, s, H-2), 8.88 (1H, d, 8.2 Hz, H-8). The individual chemical shifts, multiplicities and coupling constants for the 7.25–7.32 multiplet were obtained from undecoupled HSQC as follows: 7.240

• -dicarboxylate (4h). 0.33 g (42%) white crystals. FTIR (νmax, cm–1): 1748, 1710, 1663, 1523, 1412, 1370, 1270, 1246, 1198, 1153, 1074; 1H NMR (CDCl3) δ 3.90 (3H, s, CH3-2), 4.05 (3H, s, CH3-3), 5.47 (2H, bs, CH2), 7.22–7.33 (8H, m, aromatic rings), 7.72–7.74 (1H, m, H-9), 8.19 (1H, s, H-1). The individual

Photorelease of phosphates: Mild methods for protecting phosphate derivatives

• Sanjeewa N. Senadheera,
• Abraham L. Yousef and
• Richard S. Givens

Beilstein J. Org. Chem. 2014, 10, 2038–2054, doi:10.3762/bjoc.10.212

• energy of the naphthyl ketone platform or the disruption of both aromatic rings for the 1,5 substituted analog 27 whereas only one ring is involved for the 1,4 substituted derivative [19]. Both of the contributing components of the 2,6 pattern, 2-naphthol (ET = 60.2 kcal/mol) and 2-acetylnaphthalene (ET

• rearrangement processes for pHP. Wan’s alternative suggestion that a disruption of both aromatic rings' π-conjugation would be less favorable than only one ring’s disruption has merit. For this to be a determining factor, the disruption would have to occur prior to or during the product determining formation of

Influence of perylenediimide–pyrene supramolecular interactions on the stability of DNA-based hybrids: Importance of electrostatic complementarity

• Christian B. Winiger,
• Simon M. Langenegger,
• Oleg Khorev and
• Robert Häner

Beilstein J. Org. Chem. 2014, 10, 1589–1595, doi:10.3762/bjoc.10.164

• are strongly dependent on the electron density and distribution of the partners [2][9][13][14][15][16]. In particular, the interaction between electron-rich (donor) and electron-deficient (acceptor) aromatic rings results in stable aggregates [17][18][19][20][21][22]. In the DNA duplex, the

Homochiral BINOL-based macrocycles with π-electron-rich, electron-withdrawing or extended spacing units as receptors for C₆₀

• Marco Caricato,
• Silvia Díez González,
• Idoia Arandia Ariño and
• Dario Pasini

Beilstein J. Org. Chem. 2014, 10, 1308–1316, doi:10.3762/bjoc.10.132

• made chiral by substituting one of the nitrogen atoms, and the enantioselective complexation of chiral higher fullerenes (C84) has been demonstrated [22]. Complexes of C60 and C70 with large, calix-type macrocycles formed by π-electron deficient pyridine aromatic rings bridged by a nitrogen heteroatom

Site-selective covalent functionalization at interior carbon atoms and on the rim of circumtrindene, a C₃₆H₁₂ open geodesic polyarene

• Hee Yeon Cho,
• Ronald B. M. Ansems and
• Lawrence T. Scott

Beilstein J. Org. Chem. 2014, 10, 956–968, doi:10.3762/bjoc.10.94

• nuclei that are positioned over the faces of aromatic rings. In planar PAHs, the π-orbitals are perpendicular to the σ-bonds, the electrons are distributed equally on the two faces of the aromatic system, and the ring currents on the two faces are equivalent. When curvature is built into molecules

Direct and indirect single electron transfer (SET)-photochemical approaches for the preparation of novel phthalimide and naphthalimide-based lariat-type crown ethers

• Dae Won Cho,
• Patrick S. Mariano and
• Ung Chan Yoon

Beilstein J. Org. Chem. 2014, 10, 514–527, doi:10.3762/bjoc.10.47

• results in a close facial approach of the benzamide aromatic rings in 60, which results in intramolecular exciplex formation (Scheme 16). Conclusion Direct and indirect approaches, which rely on the use of SET-promoted photocyclization reactions of α-silyl ether-terminated, polydonor-linked, imides (e.g

The Flögel-three-component reaction with dicarboxylic acids – an approach to bis(β-alkoxy-β-ketoenamides) for the synthesis of complex pyridine and pyrimidine derivatives

• Mrinal K. Bera,
• Moisés Domínguez,
• Paul Hommes and
• Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2014, 10, 394–404, doi:10.3762/bjoc.10.37

• aromatic rings. Flögel-three-component reaction of lithiated alkoxyallenes, nitriles and carboxylic acids providing β-alkoxy-β-ketoenamides 1 – versatile precursors for the synthesis of functionalized N-heteroaromatics 2–6. Synthesis of bis(β-ketoenamides) 13–15 by three-component reactions of lithiated

The regioselective synthesis of spirooxindolo pyrrolidines and pyrrolizidines via three-component reactions of acrylamides and aroylacrylic acids with isatins and α-amino acids

• Tatyana L. Pavlovskaya,
• Fedor G. Yaremenko,
• Victoria V. Lipson,
• Svetlana V. Shishkina,
• Oleg V. Shishkin,
• Vladimir I. Musatov and
• Alexander S. Karpenko

Beilstein J. Org. Chem. 2014, 10, 117–126, doi:10.3762/bjoc.10.8

• C9–C10 endocyclic bond (the C10–C9–C14–O4 torsion angle is 10.2(4)°). Such an orientation of this substituent creates conditions for appearance of intramolecular stacking interactions between the aromatic rings of the indole fragment and the aryl substituent (angle between planes of aromatic rings is

Studies on the interaction of isocyanides with imines: reaction scope and mechanistic variations

• Ouldouz Ghashghaei,
• Consiglia Annamaria Manna,
• Esther Vicente-García,
• Marc Revés and
• Rodolfo Lavilla

Beilstein J. Org. Chem. 2014, 10, 12–17, doi:10.3762/bjoc.10.3

• it may stabilize the nitrilium intermediate precluding further addition events and leading to the aminoamides 7 after the final aqueous treatment. Furthermore, we have detected indole 6 arising from the cyclization of electron-rich aromatic rings linked to the imine nitrogen upon the electrophilic

Efficient synthesis of dihydropyrimidinones via a three-component Biginelli-type reaction of urea, alkylaldehyde and arylaldehyde

• Haijun Qu,
• Xuejian Li,
• Fan Mo and
• Xufeng Lin

Beilstein J. Org. Chem. 2013, 9, 2846–2851, doi:10.3762/bjoc.9.320

• –13). Electron-withdrawing as well as electron-donating groups on aromatic rings were tolerated, although the latter gave slightly reduced yields. It is noted that a halogen group on the aromatic ring was well tolerated to give the desired products, which can participate in subsequent transformations

Gold(I)-catalyzed domino cyclization for the synthesis of polyaromatic heterocycles

• Mathieu Morin,
• Patrick Levesque and
• Louis Barriault

Beilstein J. Org. Chem. 2013, 9, 2625–2628, doi:10.3762/bjoc.9.297

• charge build-up at the cationic cyclization transition state. Substituted aromatic compounds have a fundamental importance in organic and medicinal chemistry as well as in materials. Although there are many methods to functionalize aromatic rings, one can recognize that the above transformation

• represents an attractive and complementary approach for the synthesis of substituted aromatic rings. Taking advantage of the high regiospecificity of [L1AuNCMe][SbF6] associated with alkyne activation, we examined the scope of the reaction using various substituted alkynes (Scheme 3). Gold(I)-catalyzed

Oxidative 3,3,3-trifluoropropylation of arylaldehydes

• Akari Ikeda,
• Masaaki Omote,
• Shiho Nomura,
• Miyuu Tanaka,
• Atsushi Tarui,
• Kazuyuki Sato and
• Akira Ando

Beilstein J. Org. Chem. 2013, 9, 2417–2421, doi:10.3762/bjoc.9.279

• aldehydes in the presence of fluoride anion [29]. Recently, Prakash et al. [30] reported the synthesis of β-trifluoromethylstyrenes through a Heck coupling reaction of aryl iodides with 1-iodo-3,3,3-trifluoropropane, allowing a direct introduction of 3,3,3-trifluoropropenyl groups to aromatic rings

Synthesis of enantiopure sugar-decorated six-armed triptycene derivatives

• Paola Bonaccorsi,
• Maria Luisa Di Gioia,
• Antonella Leggio,
• Lucio Minuti,
• Teresa Papalia,
• Carlo Siciliano,
• Andrea Temperini and
• Anna Barattucci

Beilstein J. Org. Chem. 2013, 9, 2410–2416, doi:10.3762/bjoc.9.278

• the preparation of sugar-decorated triptycene derivatives. We also reasoned on the opportunity to link a significant number of carbohydrate moieties to the triptycene platform. For this reason we chose to multi-functionalize the three aromatic rings fused to the bicyclo[2.2.2]octatriene system

Synthesis of axially chiral gold complexes and their applications in asymmetric catalyses

• Yin-wei Sun,
• Qin Xu and
• Min Shi

Beilstein J. Org. Chem. 2013, 9, 2224–2232, doi:10.3762/bjoc.9.261

• structures clearly revealed the presence of a weak gold–π interaction between the Au atom and the aromatic rings in these gold complexes. Because of the gold–π interaction, the C–N bond could not rotate freely, giving two diastereomeric rotamers (S)-15a and (S)-15b. Slaughter and co-workers have also found

Regioselective 1,4-trifluoromethylation of α,β-unsaturated ketones via a S-(trifluoromethyl)diphenylsulfonium salts/copper system

• Satoshi Okusu,
• Yutaka Sugita,
• Etsuko Tokunaga and
• Norio Shibata

Beilstein J. Org. Chem. 2013, 9, 2189–2193, doi:10.3762/bjoc.9.257

• , aromatic rings substituted with either electron-donating or -withdrawing substituents, such as methyl, methoxy, fluoro and chloro were tolerated (Table 2, entries 2–4). A heteroaromatic, furanyl-substituted enone was compatible with the same reaction conditions (Table 2, entry 6). We next examined

• substrates differing in the nature of the β-aryl substituents under the same reaction conditions. A series of compounds with aromatic rings substituted with either electron-donating or -withdrawing substituents, such as methyl, methoxy, fluoro and chloro were also acceptable. Furthermore, the β-alkyl

Structure of 1,5-benzodiazepinones in the solid state and in solution: Effect of the fluorination in the six-membered ring

• Marta Pérez-Torralba,
• Rosa M. Claramunt,
• M. Ángeles García,
• Concepción López,
• M. Carmen Torralba,
• M. Rosario Torres,
• Ibon Alkorta and
• José Elguero

Beilstein J. Org. Chem. 2013, 9, 2156–2167, doi:10.3762/bjoc.9.253

• of a molecule and the F6 of a neighboring one (distance 2.875(2) Å) giving rise to a zigzag chain in the [10-1] direction (Figure 4). These chains are stacked by a partial π–π overlapping between the aromatic rings with a shortest distance of 3.19(1) Å. Compound 2 crystallizes in the triclinic P–1

• aromatic rings, with a shortest distance of 3.35(1) Å. The so formed double chains are isolated because of the above-mentioned steric reasons. We compared the geometries of compounds 3 (TUPSAZ) [8][10] and 5 (EFARUA) [8][9][10] (Figure 2) with those determined in the present work, 1 and 2. To describe the

Asymmetric allylic alkylation of Morita–Baylis–Hillman carbonates with α-fluoro-β-keto esters

• Lin Yan,
• Zhiqiang Han,
• Bo Zhu,
• Caiyun Yang,
• Choon-Hong Tan and
• Zhiyong Jiang

Beilstein J. Org. Chem. 2013, 9, 1853–1857, doi:10.3762/bjoc.9.216

• diastereoselectivities. MBH carbonates (Table 2, 2b–k) with electron-withdrawing groups appended on the aromatic rings were more active than those (Table 2, 2l–m) with electron-neutral and donating groups. Excellent ee values with moderate dr values were obtained when the phenyl groups of MBH carbonates were replaced

Anodic coupling of carboxylic acids to electron-rich double bonds: A surprising non-Kolbe pathway to lactones

• Robert J. Perkins,
• Hai-Chao Xu,
• John M. Campbell and
• Kevin D. Moeller

Beilstein J. Org. Chem. 2013, 9, 1630–1636, doi:10.3762/bjoc.9.186

• acid and an electron-rich olefin. Examples in the literature of the coupling of carboxylic acids to aromatic rings, though limited in scope, were also encouraging [16][17][18][19][20]. There are three mechanistic possibilities which would allow for a successful reaction. First, if the carboxy radical

Palladium(II)-catalyzed Heck reaction of aryl halides and arylboronic acids with olefins under mild conditions

• Tanveer Mahamadali Shaikh and
• Fung-E Hong

Beilstein J. Org. Chem. 2013, 9, 1578–1588, doi:10.3762/bjoc.9.180

• -donating group on the aromatic ring of olefin did not affect the reactivity and yield of product. The reactions led to the formation of excellent yields of the corresponding products 3e and 3f in 90% and 95% yields, respectively (Table 2, entries 7 and 8). As known, aromatic rings having substituents such

Exploration of an epoxidation–ring-opening strategy for the synthesis of lyconadin A and discovery of an unexpected Payne rearrangement

• Brad M. Loertscher,
• Yu Zhang and
• Steven L. Castle

Beilstein J. Org. Chem. 2013, 9, 1179–1184, doi:10.3762/bjoc.9.132

• ]undecanes fused to aromatic rings [11]. Then, we devised an annulation protocol inspired by the work of Donohoe and co-workers [12][13] that provided access to substituted pyridones of the type found in 1 from thioester precursors [14]. Based on these encouraging results, we decided to target lyconadin A

Interplay of ortho- with spiro-cyclisation during iminyl radical closures onto arenes and heteroarenes

• Roy T. McBurney and
• John C. Walton

Beilstein J. Org. Chem. 2013, 9, 1083–1092, doi:10.3762/bjoc.9.120

• indicating that the “default” ring closure mode for iminyl radicals is ortho-cyclisation onto suitably situated aromatic rings. The exception to this rule was spiro-cyclisation onto benzofuran and benzothiophene rings at low temperatures. Even for these acceptors, however, thermodynamic control ensured that