Thiophene-based donor–acceptor co-oligomers by copper-catalyzed 1,3-dipolar cycloaddition

• Stefanie Potratz,
• Amaresh Mishra and
• Peter Bäuerle

Beilstein J. Org. Chem. 2012, 8, 683–692, doi:10.3762/bjoc.8.76

• columns of different diameters packed with silica gel, Merck 60 (40–63 µm). Gas chromatography (GC) was carried out using a Varian CP-3800 gas chromatograph. Helium 5.0 was used as the carrier gas; signals were examined by a flame-ionization detector (FID). Gas-chromatography–mass-spectrometry (GC–MS

Volatile organic compounds produced by the phytopathogenic bacterium Xanthomonas campestris pv. vesicatoria 85-10

• Teresa Weise,
• Marco Kai,
• Anja Gummesson,
• Armin Troeger,
• Stephan von Reuß,
• Silvia Piepenborn,
• Francine Kosterka,
• Martin Sklorz,
• Ralf Zimmermann,
• Wittko Francke and
• Birgit Piechulla

Beilstein J. Org. Chem. 2012, 8, 579–596, doi:10.3762/bjoc.8.65

• growth of X. c. pv. vesicatoria were trapped on Super-Q (100 mg, Alltech Associates, Deerfield, IL, USA). The collected volatiles were eluted three times with 500 μL dichloromethane and further analysed. Gas chromatography coupled with mass spectrometry (GC/MS) was carried out by linking a gas

Cyanoethylation of the glucans dextran and pullulan: Substitution pattern and formation of nanostructures and entrapment of magnetic nanoparticles

• Kathrin Fiege,
• Heinrich Lünsdorf,
• Sevil Atarijabarzadeh and
• Petra Mischnick

Beilstein J. Org. Chem. 2012, 8, 551–566, doi:10.3762/bjoc.8.63

• (version 2.3). Peaks were identified by gas chromatography/mass spectrometry (GLC–MS) analysis. Conditions: injector 250 °C, temperature program: 60 °C (1 min); 20 °C/min to 130 °C, 4 °C/min to 260 °C, 50 °C/min to 310 °C (10 min), splitless. GLC–MS: Agilent 6890 GC (ZB5-MS column, 30 m, inner diameter

Discovery of practical production processes for arylsulfur pentafluorides and their higher homologues, bis- and tris(sulfur pentafluorides): Beginning of a new era of “super-trifluoromethyl” arene chemistry and its industry

• Teruo Umemoto,
• Lloyd M. Garrick and
• Norimichi Saito

Beilstein J. Org. Chem. 2012, 8, 461–471, doi:10.3762/bjoc.8.53

• experiment was conducted with a NMR tube. The 19F NMR was measured by using an internal standard (p-chlorobenzotrifluoride) and the NMR tube was shaken between the measurements. Gas chromatography (GC) could not be used because of decomposition of arylsulfur chlorotetrafluorides in the GC column. When a few

The volatiles of pathogenic and nonpathogenic mycobacteria and related bacteria

• Thorben Nawrath,
• Georgies F. Mgode,
• Bart Weetjens,
• Stefan H. E. Kaufmann and
• Stefan Schulz

Beilstein J. Org. Chem. 2012, 8, 290–299, doi:10.3762/bjoc.8.31

• collected by using closed-loop stripping analysis (CLSA) and were analyzed by gas-chromatography–mass-spectrometry. A wide range of compounds was produced, although the absolute amount was small. Nevertheless, characteristic bouquets of compounds could be identified. Predominantly aromatic compounds and

• described previously [15][16]. The headspace extracts were analyzed by gas-chromatography–mass-spectrometry (GC–MS). Compound identification was performed by comparison of mass spectra and gas-chromatographic retention indices with those of authentic reference compounds and mass-spectra libraries [18

The application of a monolithic triphenylphosphine reagent for conducting Appel reactions in flow microreactors

• Kimberley A. Roper,
• Heiko Lange,
• Anastasios Polyzos,
• Malcolm B. Berry,
• Ian R. Baxendale and
• Steven V. Ley

Beilstein J. Org. Chem. 2011, 7, 1648–1655, doi:10.3762/bjoc.7.194

• neighbouring-group participation assisting in the formation of the active species 9 and 10 in pathway B [39][41][42]. Analysis by gas chromatography of chloride Appel reactions indicated that the relative proportion of chloroform was a lot lower than would be expected if both pathways were followed equally in

Translation of microwave methodology to continuous flow for the efficient synthesis of diaryl ethers via a base-mediated S_NAr reaction

• Charlotte Wiles and
• Paul Watts

Beilstein J. Org. Chem. 2011, 7, 1360–1371, doi:10.3762/bjoc.7.160

• samples by gas chromatography-flame ionisation detection (GC-FID) were performed on a Varian GC (430) with a CP-Sil 8 (30 m) column (Phenomenex, UK) and ultrahigh purity helium (99.9999%, Energas, UK) as the carrier gas. Reaction products were analysed by the following method; injector temperature 200 °C

Novel synthesis of pseudopeptides bearing a difluoromethyl group by Ugi reaction and desulfanylation

• Jingjing Wu,
• Hui Li and
• Song Cao

Beilstein J. Org. Chem. 2011, 7, 1070–1074, doi:10.3762/bjoc.7.123

• as standard. Gas chromatography-mass spectra (GC-MS) were recorded on HP 5973 MSD with 6890 GC. High resolution mass spectra (HRMS) were recorded under electron impact conditions using a MicroMass GCT CA 055 instrument and recorded on a MicroMass LCTTM spectrometer. Column chromatography was carried

Studies on Pd/NiFe₂O₄ catalyzed ligand-free Suzuki reaction in aqueous phase: synthesis of biaryls, terphenyls and polyaryls

• Sanjay R. Borhade and
• Suresh B. Waghmode

Beilstein J. Org. Chem. 2011, 7, 310–319, doi:10.3762/bjoc.7.41

• reflux condenser, were added the aryl halide (1 mmol), boronic acid (1.25 mmol), Na2CO3 (2 mmol), and Pd/NiFe2O4 (0.1 mol %) in 4 mL DMF/H2O (1:1), and the reaction mixture heated at the appropriate temperature and duration. The reaction was monitored by gas chromatography. After the reaction was

Synthesis of cationic dibenzosemibullvalene-based phase-transfer catalysts by di-π-methane rearrangements of pyrrolinium-annelated dibenzobarrelene derivatives

• Heiko Ihmels and
• Jia Luo

Beilstein J. Org. Chem. 2011, 7, 119–126, doi:10.3762/bjoc.7.17

• . Calcd for C26H32ClNO4 (458.0): C, 68.18; H, 7.04; N, 3.06. Found: C, 68.22; H, 7.14; N, 3.06. Phase-transfer catalyzed (PTC) alkylation reactions a) Analysis with gas chromatography: A biphasic mixture of the quaternary ammonium catalyst 3d or TBAC (0.05 mmol), phenylacetonitrile (5, 506 mg, 4.32 mmol

• ) and bromoethane (808 mg, 4.75 mmol) in toluene (0.85 ml) and aqueous KOH solution (4 ml, 60%) was stirred for 2 h at 20 °C. Water (10 ml) and toluene (10 ml) were added and the mixture was thoroughly shaken. After phase separation, the organic layer was analyzed by gas chromatography. Stationary Phase

The cross-metathesis of methyl oleate with cis-2-butene-1,4-diyl diacetate and the influence of protecting groups

• Arno Behr and
• Jessica Pérez Gomes

Beilstein J. Org. Chem. 2011, 7, 1–8, doi:10.3762/bjoc.7.1

• the reaction equilibrium towards the cross-metathesis products 3 and 4. The differences in metathesis activity of these investigated metathesis initiators are presented in Table 1. Both conversions of 1 and yields of the cross-metathesis products 3 and 4 were determined by gas chromatography with

• mixture was cooled to ambient temperature. Conversion and yield analyses were performed by gas chromatography. The metathesis products were isolated after removing toluene in vacuo by flash chromatography on silica gel with cyclohexane/ethyl acetate (from 10/1 to 1/2) as eluent, and subsequently

Functionalized copolyimide membranes for the separation of gaseous and liquid mixtures

• Nadine Schmeling,
• Roman Konietzny,
• Daniel Sieffert,
• Patrick Rölling and
• Claudia Staudt

Beilstein J. Org. Chem. 2010, 6, 789–800, doi:10.3762/bjoc.6.86

• selectivity can be calculated from Equation 6. In which xi is the mole fraction of the preferred permeating component i on the feed side and yi is the mole fraction of the preferred permeating component i on the permeate side, as measured by gas chromatography. Results and Discussion Material selection For

Solvent-free and time-efficient Suzuki–Miyaura reaction in a ball mill: the solid reagent system KF–Al₂O₃ under inspection

• Franziska Bernhardt,
• Ronald Trotzki,
• Tony Szuppa,
• Achim Stolle and
• Bernd Ondruschka

Beilstein J. Org. Chem. 2010, 6, No. 7, doi:10.3762/bjoc.6.7

• = 45 ml) of nearly the same weight were placed inside the ball mill. The purity of all the compounds was checked using capillary gas chromatography. Analyses of the reaction mixtures were carried out by GC-FID and GC-MSD. Conditions GC-FID: HP 5, 30 m × 0.32 mm × 0.25 µm, H2 – 12 psi, program: 50 °C

Acid- mediated reactions under microfluidic conditions: A new strategy for practical synthesis of biofunctional natural products

• Katsunori Tanaka and
• Koichi Fukase

Beilstein J. Org. Chem. 2009, 5, No. 40, doi:10.3762/bjoc.5.40

• based on gas chromatography analysis. Since the present pristane synthesis involves only one simple purification step by filtration with a silica gel pad, we believe that our protocol is superior to the hitherto known synthesis, which involves purification by tedious multiple distillation at the final

The development and evaluation of a continuous flow process for the lipase- mediated oxidation of alkenes

• Charlotte Wiles,
• Marcus J. Hammond and
• Paul Watts

Beilstein J. Org. Chem. 2009, 5, No. 27, doi:10.3762/bjoc.5.27

• obtained were consistent with the literature. The following abbreviations are used to report NMR spectroscopic data; s = singlet, d = doublet, t = triplet, br s = broad singlet, q = quartet, dd = double doublet, dt = doublet of triplets, m = multiplet and C0 = quaternary carbon. Analysis of samples by Gas

• Chromatography-Mass Spectrometry (GC-MS) were performed using a Varian GC (CP-3800) coupled to a Varian MS (2100T) with a CP-Sil 8 (30 m) column (Phenomenex, UK) and ultra high purity helium (99.9999%, Energas, UK) as the carrier gas. Reactions employing 1-methylcyclohexene (6), cyclohexene (10), styrene (9

An expedient synthesis of 5-n-alkylresorcinols and novel 5-n-alkylresorcinol haptens

• Kirsti Parikka and
• Kristiina Wähälä

Beilstein J. Org. Chem. 2009, 5, No. 22, doi:10.3762/bjoc.5.22

• , including human plasma [15], human and animal ileostomy fluids [16][17] and e.g. perirenal adipose tissue [18], has mainly been performed by gas chromatography-mass spectrometry (GC-MS) requiring time-consuming sample preparation such as extraction, derivatisation, chromatography, and special equipment

A biphasic oxidation of alcohols to aldehydes and ketones using a simplified packed- bed microreactor

• Andrew Bogdan and
• D. Tyler McQuade

Beilstein J. Org. Chem. 2009, 5, No. 17, doi:10.3762/bjoc.5.17

• constant at 220 and 250 °C, respectively. Cyclooctane was used as an internal standard to calculate reaction conversion and yield. Gas chromatography-mass spectrometry (GC/MS) analyses were performed using a Hewlett Packard HP 6890 Series Gas Chromatograph, a Hewlett Packard HP 5973 Mass Spectrometer

Synthesis of unsymmetrically substituted biaryls via sequential lithiation of dibromobiaryls using integrated microflow systems

• Aiichiro Nagaki,
• Naofumi Takabayashi,
• Yutaka Tomida and
• Jun-ichi Yoshida

Beilstein J. Org. Chem. 2009, 5, No. 16, doi:10.3762/bjoc.5.16

• . After stirring methanol was added, and the mixture was stirred for 10 min. Then, the solution was analyzed by gas chromatography (GC) to determine the yields of 2-bromobiphenyl (2, product derived from monolithiation) and biphenyl (3, product derived from dilithiation). As shown in Table 1, 2 was