Search Results - "Böhrer, Petra"

Formation of Organozincate Anions in LiCl-Mediated Zinc Insertion Reactions by Koszinowski, Konrad, Böhrer, Petra

“…Tetrahydrofuran solutions of the products formed in LiCl-mediated zinc insertion reactions into various organic halides RHal were analyzed by anion-mode…”
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Aggregation and Reactivity of Organozincate Anions Probed by Electrospray Mass Spectrometry by Koszinowski, Konrad, Böhrer, Petra

“…Electrospray ionization (ESI) of mixtures of organolithium compounds and zinc chloride in tetrahydrofuran produced manifold mono- and polynuclear organozincate…”
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Kinetics of α‑(2,6-Dimethylphenl)vinyllithium: How To Control Errors Caused by Inefficient Mixing with Pairs of Rapidly Competing Ketones by Knorr, Rudolf, Knittl, Monika, Behringer, Claudia, Ruhdorfer, Jakob, Böhrer, Petra

“…Kinetic studies are a suitable tool to disclose the role of tiny reagent fractions. The title compound 2 reacted in a kinetic reaction order of 0.5 (square…”
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Unusual traits of cis and trans-2,3-dibromo-1,1-dimethylindane on the way from 1,1-dimethylindene to 2-bromo-, 3-bromo-, and 2,3-dibromo-1,1-dimethylindene by Knorr, Rudolf, Stephenson, David S, Lattke, Ernst, Böhrer, Petra, Ruhdorfer, Jakob

“…Do not rely on the widely accepted rule that vicinal, sp(3)-positioned protons in cyclopentene moieties should always have more positive (3) J NMR coupling…”
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Total Synthesis of Flustramine C via Dimethylallyl Rearrangement by Lindel, Thomas, Bräuchle, Laura, Golz, Gregor, Böhrer, Petra

“…The marine natural product flustramine C from the bryozoan Flustra foliacea was synthesized in five steps and 38% yield starting from N b-methyltryptamine. The…”
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Carbenoid Chain Reactions:  Substitutions by Organolithium Compounds at Unactivated 1-Chloro-1-alkenes by Knorr, Rudolf, Pires, Claudio, Behringer, Claudia, Menke, Thomas, Freudenreich, Johannes, Rossmann, Eva C, Böhrer, Petra

“…The deceptively simple “cross-coupling” reactions Alk2CCA−Cl + RLi → Alk2CCA−R + LiCl (A = H, D, or Cl) occur via an alkylidenecarbenoid chain mechanism in…”
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"Conducted Tour" Migration of Li+ during the cis/trans Stereoinversion of [alpha]-Arylvinyllithiums by Knorr, Rudolf, Behringer, Claudia, Ruhdorfer, Jakob, vonRoman, Ulrich, Lattke, Ernst, Bohrer, Petra

“…A "conducted tour" migration keeps a mobile client on a profitable route even though an occasional side-step may seem attractive. A stereochemical…”
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Highly syn selective addition of aqueous HBr to hydrophobically shielded arylalkynes by Knorr, Rudolf, Rossmann, Eva C., Knittl, Monika, Böhrer, Petra

“…Hydrophobically shielded alkynes HCC–aryl, carrying 2,6-di- and 2,4,6-tri-tert-butylphenyl as the aryl group, can add aqueous HBr on heating in moist…”
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Demonstration of NC(sp2)‐centered stereofluctuations in a guanidine derivative and its cation by Knorr, Rudolf, Böhrer, Petra

“…NMR line shapes and coalescences of pairs of diastereotopic reporter nuclei (1H and 13C) at suitable molecular positions were used to measure the…”
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Short Syntheses of some ‘Decalin‐1,8‐diones’ and their Derivatives: Breaking the Pretended Symmetry by Knorr, Rudolf, Nadolny, Annette, Hauer, Hermann, Böhrer, Petra

“…A cheap synthesis of the so‐called ‘decalin‐1,8‐diones’ started with the conjugate (1,4‐) addition of cyclohex‐2‐en‐1‐one derivatives to the γ‐position of the…”
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Microsolvation, Dimerization, and sp 2 -Stereoinversion of Monomeric α-(2,6-Diisopropylphenyl)vinyllithium by Knorr, Rudolf, Ruhdorfer, Jakob, Böhrer, Petra

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Unpaired Spin Densities from NMR Shifts † and Magnetic Anisotropies of Pseudotetrahedral Cobalt(II) and Nickel(II) Vinamidine Bis(chelates) by Knorr, Rudolf, Hauer, Hermann, Weiss, Alfons, Polzer, Heinz, Ruf, Friedrich, Löw, Peter, Dvortsák, Peter, Böhrer, Petra

“…The distribution of unpaired electron spin over all regions of the organic ligands was extracted from the large positive and negative 1H and 13C NMR…”
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“Conducted Tour” Migration of Li+ during the cis/trans Stereoinversion of α‐Arylvinyllithiums by Knorr, Rudolf, Behringer, Claudia, Ruhdorfer, Jakob, von Roman, Ulrich, Lattke, Ernst, Böhrer, Petra

“…A “conducted tour” migration keeps a mobile client on a profitable route even though an occasional side‐step may seem attractive. A stereochemical…”
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What can 13C and 1H NMR lithiation shifts tell us about the charge distribution in α-arylvinyllithium compounds? by Knorr, Rudolf, Lattke, Ernst, Ruhdorfer, Jakob, von Roman, Ulrich, Firl, Joachim, Böhrer, Petra

“…The energetically stabilizing delocalization of negative electric charge from the LiC(α) bond into the aryl π system of α-arylvinyllithiums, ArC(Li)CH2, is…”
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Microsolvation, aggregation, and pseudomonomolecular, ionic sp2-stereoinversion mechanism of two exocyclic β,β-di-tert-alkyl-α-arylvinyllithiums by Knorr, Rudolf, Hennig, Karsten-Olaf, Böhrer, Petra, Schubert, Bernhard

“…A THF-solvated, crystalline, exocyclic alkenyllithium, (tert-alkyl)2CC(Li)–Ph, was synthesized and shown to be a disolvated dimer in the solid state and in…”
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Ring expansion and vinylic nucleophilic substitution competing for (tert-alkyl)2CC(Li)–Cl in carbenoid chain processes by Knorr, Rudolf, Menke, Thomas, Hennig, Karsten-Olaf, Freudenreich, Johannes, Böhrer, Petra, Schubert, Bernhard

“…Vinylic nucleophilic substitution (SNV) reactions of unactivated, cyclic α,α-dichloroalkenes [(tert-alkyl)2CCCl2] with aryllithiums (RLi) to give…”
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Shorter and Easier Syntheses of Di-tert-butylketene and Related gem-Di-tert-butyl Compounds by Knorr, Rudolf, Hennig, Karsten-Olaf, Schubert, Bernhard, Böhrer, Petra

“…The ketene tBu2C=C=O is prepared from tBu2C=O in three steps (performable as a two‐stage operation) through elimination of HCl from the intermediate product…”
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Microsolvation, Dimerization, and sp2‑Stereoinversion of Monomeric α‑(2,6-Diisopropylphenyl)vinyllithium by Knorr, Rudolf, Ruhdorfer, Jakob, Böhrer, Petra

“…The title compound is entirely monomeric in THF as the solvent, but its two ortho-diisopropyl substituents (in contrast to two tert-butyl groups) do not…”
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Ring expansion and vinylic nucleophilic substitution competing for (tert-alkyl) sub(2)CC(Li)-Cl in carbenoid chain processes by Knorr, Rudolf, Menke, Thomas, Hennig, Karsten-Olaf, Freudenreich, Johannes, Bohrer, Petra, Schubert, Bernhard

“…Vinylic nucleophilic substitution (S sub(N)V) reactions of unactivated, cyclic alpha , alpha -dichloroalkenes [(tert-alkyl) sub(2)CCCl sub(2)] with…”
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