My maize and blue brick road to physical organic chemistry in materials

• Anne J. McNeil

Beilstein J. Org. Chem. 2016, 12, 229–238, doi:10.3762/bjoc.12.24

• , might be gelators. We searched the CSD for molecules containing a mercury atom (Hg2+) that was involved in an intermolecular cation–π interaction [28]. We identified molecule 2a, which exhibited 1D π–cation–π interactions in the solid state (Figure 3). Graduate student Kelsey (King) Carter synthesized

Synthesis of cyclic N¹-pentylinosine phosphate, a new structurally reduced cADPR analogue with calcium-mobilizing activity on PC12 cells

• Ahmed Mahal,
• Stefano D’Errico,
• Nicola Borbone,
• Brunella Pinto,
• Agnese Secondo,
• Valeria Costantino,
• Valentina Tedeschi,
• Giorgia Oliviero,
• Vincenzo Piccialli and
• Gennaro Piccialli

Beilstein J. Org. Chem. 2015, 11, 2689–2695, doi:10.3762/bjoc.11.289

• . 1H and 13C NMR experiments were performed using a Varian Mercury Plus 400 MHz spectrometer in CD3OD, D2O, CDCl3 and acetone-d6 solvents. Chemical shifts are reported in parts per million (δ) relative to residual solvents signals: CD2HOD 3.31, HOD 4.80, (CD3)(CD2H)CO 2.09 for 1H NMR and CD3OD 49.0 for

Exploring architectures displaying multimeric presentations of a trihydroxypiperidine iminosugar

• Camilla Matassini,
• Stefania Mirabella,
• Andrea Goti,
• Inmaculada Robina,
• Antonio J. Moreno-Vargas and
• Francesca Cardona

Beilstein J. Org. Chem. 2015, 11, 2631–2640, doi:10.3762/bjoc.11.282

• plates (Merck F254). Column chromatographies were carried out on Silica Gel 60 (32–63 μm) or on silica gel (230–400 mesh, Merck). Yields refer to spectroscopically and analytically pure compounds unless otherwise stated. 1H NMR spectra were recorded on a Varian Mercury-400 or on a Varian INOVA 400

Effective ascorbate-free and photolatent click reactions in water using a photoreducible copper(II)-ethylenediamine precatalyst

• Redouane Beniazza,
• Natalia Bayo,
• Florian Molton,
• Carole Duboc,
• Stéphane Massip,
• Nathan McClenaghan,
• Dominique Lastécouères and
• Jean-Marc Vincent

Beilstein J. Org. Chem. 2015, 11, 1950–1959, doi:10.3762/bjoc.11.211

• mercury lamp (type TLC = thin-layer chromatography, 365 nm), or by a 23 W fluorescent bulb, or by ambient/sunlight. In water, a much poorer hydrogen atom donating solvent, the photoreduction of 1 proved inefficient. Interestingly, EPR studies revealed that complex 1 could nonetheless be effectively

Polythiophene and oligothiophene systems modified by TTF electroactive units for organic electronics

• Alexander L. Kanibolotsky,
• Neil J. Findlay and
• Peter J. Skabara

Beilstein J. Org. Chem. 2015, 11, 1749–1766, doi:10.3762/bjoc.11.191

• required for this, 4,6-dibromothieno[3,4-d][1,3]dithiole-2-one (15b), can be efficiently obtained by brominating compound 15a, which in turn is synthesised by mercury(II) acetate assisted transchalcogenation reaction from the corresponding thione 17. Unsubstituted thieno[3,4-d][1,3]dithiole-2-thione (17

A facile synthetic route to benzimidazolium salts bearing bulky aromatic N-substituents

• Gabriele Grieco,
• Olivier Blacque and
• Heinz Berke

Beilstein J. Org. Chem. 2015, 11, 1656–1666, doi:10.3762/bjoc.11.182

• } NMR data were recorded on a Varian Gemini-300, a Varian Mercury 200 or Bruker DRX 500 spectrometer using 5 mm diameter NMR tubes. Chemical shifts are expressed in parts per million (ppm). 1H and 13C{1H} NMR spectra were referenced to the residual proton or 13C resonances of the deuterated solvent

Selected synthetic strategies to cyclophanes

• Sambasivarao Kotha,
• Mukesh E. Shirbhate and
• Gopalkrushna T. Waghule

Beilstein J. Org. Chem. 2015, 11, 1274–1331, doi:10.3762/bjoc.11.142

The synthesis of active pharmaceutical ingredients (APIs) using continuous flow chemistry

• Marcus Baumann and
• Ian R. Baxendale

Beilstein J. Org. Chem. 2015, 11, 1194–1219, doi:10.3762/bjoc.11.134

• -polymer tubing wrapped around a cooled medium pressure mercury lamp was used to efficiently generate and react the singlet oxygen in the presence of tetraphenylporphyrin (TPP) as a photosensitizer. Upon exiting the photoreactor, the reaction stream was acidified by combining with a stream of TFA in order

Cathodic hydrodimerization of nitroolefins

• Michael Weßling and
• Hans J. Schäfer

Beilstein J. Org. Chem. 2015, 11, 1163–1174, doi:10.3762/bjoc.11.131

• 85% to 92% yield at a mercury pool cathode and with slightly lower yields at a graphite cathode [5][6][7][8]. The current controlled reduction of alkyl- and aryl-substituted nitroalkenes in acidic medium affords mixtures of ketones and oximes in yields of 39% to 72% [9] and 55% to 91% [10

• the cathode material mercury against the environmentally benign graphite. At a graphite cathode the nitroolefin 1 could be hydrodimerized to the dimer 2. With 60% the yield is lower than in the reduction at the Hg cathode, where 88% of the dimer were obtained. Possibly higher yields can be obtained

• with other graphite varieties or other nontoxic cathode materials. But in principle the mercury cathode can be replaced by a graphite cathode. Structure of the hydrodimers All products show for the nitro group characteristic asymmetrical and symmetrical vibrations at 1530–1560 cm−1 and 1350–1360 cm−1

New tris- and pentakis-fused donors containing extended tetrathiafulvalenes: New positive electrode materials for rechargeable batteries

• Shintaro Iwamoto,
• Yuu Inatomi,
• Daisuke Ogi,
• Satoshi Shibayama,
• Yukiko Murakami,
• Minami Kato,
• Kazuyuki Takahashi,
• Kazuyoshi Tanaka,
• Nobuhiko Hojo and
• Yohji Misaki

Beilstein J. Org. Chem. 2015, 11, 1136–1147, doi:10.3762/bjoc.11.128

• undesired byproducts. The homo-coupling reaction using 11 might give 12 in a good yield, however, toxic and expensive mercury(II) acetate has to be used for the synthesis of 11. Thus, the cross-coupling reaction is useful for saving 11. The Horner–Wadsworth–Emmons reaction of 12 with 2 equiv of aldehydes

A new and convenient synthetic way to 2-substituted thieno[2,3-b]indoles

• Roman A. Irgashev,
• Arseny A. Karmatsky,
• Gennady L. Rusinov and
• Valery N. Charushin

Beilstein J. Org. Chem. 2015, 11, 1000–1007, doi:10.3762/bjoc.11.112

• , 1871, 1909, 1936, 1969, 2332, 2736, 2889, 2936, 2974, 2989, 3075, 3058 cm−1; Anal. calcd for C18H14N2O2S: C, 67.06; H, 4.38; N, 8.69; found: C, 66.98; H, 4.35; N, 8.72. Natural and synthetic derivatives of thieno[2,3-b]indole. Mercury [34] representation of the X-ray crystal structure of 12a. Thermal

Synthesis and characterization of the cyanobenzene-ethylenedithio-TTF donor

• Sandrina Oliveira,
• Dulce Belo,
• Isabel C. Santos,
• Sandra Rabaça and
• Manuel Almeida

Beilstein J. Org. Chem. 2015, 11, 951–956, doi:10.3762/bjoc.11.106

• anisotropic thermal parameters whereas H-atoms were placed in idealised positions and allowed to refine riding on the parent C atom. Molecular graphics were prepared using MERCURY 1.4.2 [29]. General procedure for the synthesis of 3 In freshly destilled triethyl phosphite (10 mL), 2-thioxobenzo[d][1,3

Mechanical stability of bivalent transition metal complexes analyzed by single-molecule force spectroscopy

• Manuel Gensler,
• Christian Eidamshaus,
• Maurice Taszarek,
• Hans-Ulrich Reissig and
• Jürgen P. Rabe

Beilstein J. Org. Chem. 2015, 11, 817–827, doi:10.3762/bjoc.11.91

• Si3N4 cantilevers (Olympus Biolever, 60 µm short cantilever: k = 0.03 N/M, 100 µm long cantilever: k = 0.006 N/m, Olympus Corp., Tokyo, Japan) were cleaned by UV/O3 treatment [53] (Penray low-pressure mercury discharge tube, UVP, Upland, CA) and treated as gold supports above. SMF measurements were

Sequence-specific RNA cleavage by PNA conjugates of the metal-free artificial ribonuclease tris(2-aminobenzimidazole)

• Friederike Danneberg,
• Alice Ghidini,
• Plamena Dogandzhiyski,
• Elisabeth Kalden,
• Roger Strömberg and
• Michael W. Göbel

Beilstein J. Org. Chem. 2015, 11, 493–498, doi:10.3762/bjoc.11.55

• required an HgO induced cyclization step, a mercury free variant is described herein. Keywords: antisense; fluorescence correlation spectroscopy; guanidine; miRNA 20a; peptide nucleic acids; Introduction Sequence specific artificial ribonucleases are an attractive research target for several reasons. On

• of toxic mercury(II) oxide for the formation of the benzimidazole moieties (Scheme 1) is a disadvantage of this synthesis especially with regard to future biological applications of the final product. Furthermore, conditions for these reactions are rather harsh and the yields may differ considerably

• . Here we report a new and mercury-free synthesis of tris(2-aminobenzimidazole) and its conjugation to PNA oligomers. In addition, the results of cleaving experiments with three different RNA substrates are presented. Results and Discussion Alternative reagents to convert thioureas into guanidines

Bis(vinylenedithio)tetrathiafulvalene analogues of BEDT-TTF

• Erdal Ertas,
• İlknur Demirtas and
• Turan Ozturk

Beilstein J. Org. Chem. 2015, 11, 403–415, doi:10.3762/bjoc.11.46

• of the side products 16–19 can be taken as evidence for the proposed reaction mechanism. The thione sulfur atoms of 11a–d and 13a–c were converted into their corresponding oxo forms 26a–d and 27a–c, respectively, using mercury acetate (Scheme 4) [46][53][54]. These were then subjected to cross

• lead to side products during the coupling reaction, performed using triethyl phosphite, and the reaction for conversion of the thione group to a keto group with mercury acetate and acetic acid, they were protected by reaction with methoxyethoxymethylchloride (CH3OCH2CH2OCH2Cl, MEMCl) to obtain 62. The

• which with P4S10 in acidic and basic conditions produced 1,4-dithiin 75 (75%) and thiophene 76 (57%) rings, respectively. They were then converted into their corresponding oxo forms 77 (65%) and 78 (77%), respectively, with mercury acetate and subjected to the coupling reaction with triethyl phosphite

Stereoselective cathodic synthesis of 8-substituted (1R,3R,4S)-menthylamines

• Carolin Edinger,
• Jörn Kulisch and
• Siegfried R. Waldvogel

Beilstein J. Org. Chem. 2015, 11, 294–301, doi:10.3762/bjoc.11.34

• Discussion Exploratory work Our previous studies revealed that menthone oxime can be electrochemically reduced on either mercury pool or lead cathode (see Scheme 4) [26]. Under optimized reaction conditions, the use of a mercury pool cathode renders compound 3 in 86% yield with a diastereomeric ratio (dr) 3a

• that the reduction of the non-substituted menthone oxime was most effective on mercury or lead as cathodic material [26], we were prompted to study the influence of such cathodes onto yield and stereoselectivity in the conversion of 7a (see Scheme 6). The results clearly indicate that lead represents

• the superior cathode for this application. Compared to mercury, the use of a lead cathode renders significantly higher yields (93% vs 19%). Furthermore, an improved dr of 8:1 in favor of the desired isomer 8a is obtained (compare dr = 6:1 obtained at Hg). Both results clearly demonstrate the positive

Cross-dehydrogenative coupling for the intermolecular C–O bond formation

• Igor B. Krylov,
• Vera A. Vil’ and
• Alexander O. Terent’ev

Beilstein J. Org. Chem. 2015, 11, 92–146, doi:10.3762/bjoc.11.13

• under irradiation of its alcoholic solutions with a mercury lamp in an oxygen atmosphere; esters were obtained in higher yields in the presence of catalytic amounts of HCl [172]. The formation of primary and secondary alcohol esters was observed after the ozonolysis of a mixture of aldehyde and alcohol

Synthesis and characterization of a new photoinduced switchable β-cyclodextrin dimer

• Florian Hamon,
• Claire Blaszkiewicz,
• Marie Buchotte,
• Estelle Banaszak-Léonard,
• Hervé Bricout,
• Sébastien Tilloy,
• Eric Monflier,
• Christine Cézard,
• Laurent Bouteiller,
• Christophe Len and
• Florence Djedaini-Pilard

Beilstein J. Org. Chem. 2014, 10, 2874–2885, doi:10.3762/bjoc.10.304

• /ethyl acetate. Ratios are specified in each case in the experimental section. Products were illuminated under UV light (λ = 254 nm) followed by charring with vanillin/H2SO4. UV analyses were performed on a UV–vis Cary VARIAN spectrophotometer coupled with an optic fiber. A 6 Watt mercury lamp was used

Design and synthesis of novel bis-annulated caged polycycles via ring-closing metathesis: pushpakenediol

• Sambasivarao Kotha and
• Mirtunjay Kumar Dipak

Beilstein J. Org. Chem. 2014, 10, 2664–2670, doi:10.3762/bjoc.10.280

• carried out by means of Chem Draw 3D and the structure was visualized with the Mercury software (Figure 3). We turned our attention toward the next target, i.e., the symmetrical heptacyclic diol 27, by adopting the ring-rearrangement metathesis (RRM) protocol [42]. To this end, hexacyclic diones 23 [28

Electrocarboxylation: towards sustainable and efficient synthesis of valuable carboxylic acids

• Roman Matthessen,
• Jan Fransaer,
• Koen Binnemans and
• Dirk E. De Vos

Beilstein J. Org. Chem. 2014, 10, 2484–2500, doi:10.3762/bjoc.10.260

• [41][42]. Hydrogen formation can be limited by usage of cathode materials with high hydrogen overvoltage like lead and mercury, or more environmentally friendly tantalum and zinc [43]. In order to minimize other side reactions a cation exchange membrane (CEM) is necessary, allowing different

• -butadiene in a two-compartment cell with a mercury cathode and a platinum anode, giving a mixture of mono- and dicarboxylic acids. CO2 bubbling through a catholyte solution of 1 wt % water in DMF, saturated with butadiene, yielded up to 50% of 3-hexenedioic acid [45], a result which unfortunately was

• generated at the anode, cathodes with high hydrogen overpotential, like mercury and lead, are necessary to minimize current loss through hydrogen gas formation [41][42]. The counter ion seems to have a significant influence on the fate of the cathodically formed CO2•− radical anion. For carboxylation of a

Second generation silver(I)-mediated imidazole base pairs

• Susanne Hensel,
• Nicole Megger,
• Kristina Schweizer and
• Jens Müller

Beilstein J. Org. Chem. 2014, 10, 2139–2144, doi:10.3762/bjoc.10.221

• (Figure 1). This contrasts the situation in a duplex with thyminate–Hg(II)–thyminate base pairs (Scheme 1, bottom) [31][32]. As a result of the keto groups on the thymine residues, the mercury(II) ions included in this type of metal-mediated base pair are clearly shielded from outside access [31]. In an

Photo, thermal and chemical degradation of riboflavin

• Muhammad Ali Sheraz,
• Sadia Hafeez Kazi,
• Sofia Ahmed,
• Zubair Anwar and
• Iqbal Ahmad

Beilstein J. Org. Chem. 2014, 10, 1999–2012, doi:10.3762/bjoc.10.208

• (medium pressure mercury vapor lamp, 125 W), i.e., 2.19 ± 0.12 × 1018 quanta s−1 as compared to the visible sources (high pressure mercury vapor fluorescent lamp, 125 W and tungsten lamp, 150 W), i.e., 1.14 ± 0.10 × 1017 and 1.06 ± 0.11 × 1016 quanta s−1, respectively [24][26]. Previously it was reported

• photodegradation of RF in aqueous solution. log k–pH profiles for the photolysis of RF in aqueous solution using UV light (∆) and visible light (○). UV lamp emission at 313 and 366 nm (125 W medium pressure mercury vapor lamp, 2.19 ± 0.12 × 1018 quanta s−1), Visible lamp emission at 405 and 435 nm (Philips HPL N

• 125 W high pressure mercury vapor fluorescent lamp, 1.14 ± 0.10 × 1017 quanta s−1). Reproduced with permission from [24]. Copyright 2004 Elsevier. log k–pH profiles for the photolysis of FMF (10−4 M) in alkaline solution under aerobic (○) and anaerobic (∆) conditions irradiated for 1 h at 25 ± 1 °C

Copolymerization and terpolymerization of carbon dioxide/propylene oxide/phthalic anhydride using a (salen)Co(III) complex tethering four quaternary ammonium salts

• Jong Yeob Jeon,
• Seong Chan Eo,
• Jobi Kodiyan Varghese and
• Bun Yeoul Lee

Beilstein J. Org. Chem. 2014, 10, 1787–1795, doi:10.3762/bjoc.10.187

• over CaH2 and then vacuum-transferred to a reservoir. PA was purchased from Aldrich and purified by recrystallization in ethyl acetate. 1H NMR (400 MHz) and 13C NMR (100 MHz) spectra were recorded on a Varian Mercury Plus 400 instrument. Gel permeation chromatography (GPC) was performed in THF at 40 °C

Bifunctional dendrons for multiple carbohydrate presentation via carbonyl chemistry

• Davide Bini,
• Francesco Nicotra and
• Laura Cipolla

Beilstein J. Org. Chem. 2014, 10, 1686–1691, doi:10.3762/bjoc.10.177

• performed on silica gel 230–400 mesh (Merck). Routine 1H and 13C NMR spectra were recorded on a Varian Mercury instrument at 400 MHz (1H) and 100.57 MHz (13C). Chemical shifts are reported in parts per million downfield from TMS as an internal standard, J values are given in Hz. Mass spectra were recorded

An experimental and theoretical NMR study of NH-benzimidazoles in solution and in the solid state: proton transfer and tautomerism

• Carla I. Nieto,
• Pilar Cabildo,
• M. Ángeles García,
• Rosa M. Claramunt,
• Ibon Alkorta and
• José Elguero

Beilstein J. Org. Chem. 2014, 10, 1620–1629, doi:10.3762/bjoc.10.168

• of programs. The five studied compounds. Trimers A (left) and B (right) of 1. The tautomerism of 1H-benzimidazole. The 13C CPMAS NMR spectrum of 3. The two independent molecules of 3 drawn with the Mercury program [26]. The evolution of the spectrum of 1 with temperature in HMPA-d18. Calculated and