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Search for "substitution reactions" in Full Text gives 132 result(s) in Beilstein Journal of Organic Chemistry.

Gold(I)-catalyzed hydroarylation reaction of aryl (3-iodoprop-2-yn-1-yl) ethers: synthesis of 3-iodo-2H-chromene derivatives

  • Pablo Morán-Poladura,
  • Eduardo Rubio and
  • José M. González

Beilstein J. Org. Chem. 2013, 9, 2120–2128, doi:10.3762/bjoc.9.249

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  • pattern is not the one commonly associated with conventional electrophilic aromatic substitution reactions, other mechanism should not be disregarded on the basis of the structure of the final product. So, the alternative mechanistic description summarized in Scheme 4B cannot be firmly rejected, at the
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Published 16 Oct 2013

Enantioselective synthesis of planar chiral ferrocenes via palladium-catalyzed annulation with diarylethynes

  • Yan-Chao Shi,
  • Rong-Fei Yang,
  • De-Wei Gao and
  • Shu-Li You

Beilstein J. Org. Chem. 2013, 9, 1891–1896, doi:10.3762/bjoc.9.222

Graphical Abstract
  • ). The allylic substitution reactions of (rac)-4 had been carried out. The allylic alkylation reaction proceeded in 95% yield and 44% ee (Scheme 3, reaction 1) and the allylic amination reaction proceeded in 32% yield and 43% ee (Scheme 3, reaction 2) [69][70][71]. Although only moderate
  • could be transformed readily into a P,N-ligand, which was found to be suitable for Pd-catalyzed allylic substitution reactions. Experimental General procedure for the enantioselective synthesis of planar chiral ferrocenes To a solution of alkyne 2 (0.46 mmol) in DMA (1.5 mL) was added Boc-L-Val-OH (8.7
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Published 18 Sep 2013

The first example of the Fischer–Hepp type rearrangement in pyrimidines

  • Inga Cikotiene,
  • Mantas Jonusis and
  • Virginija Jakubkiene

Beilstein J. Org. Chem. 2013, 9, 1819–1825, doi:10.3762/bjoc.9.212

Graphical Abstract
  • , nucleophilic aromatic substitution reactions of halopyrimidines are smooth and high-yielding, especially when an electron-withdrawing group is present in this heterocycle. It is noteworthy that in the case of non-activated dihalopyrimidines, the first nucleophilic displacement reaction deactivates the
  • triethylamine at room temperature, a smooth completion of the nucleophilic substitution reactions was observed by TLC. Then the solutions were diluted with 50% (v/v) sulfuric acid, and the resultant yellow colored mixtures were stirred at room temperature for 15 min. After the work-up of the reaction mixtures
  • ]+ calcd for C16H21N5NaOS, 354.1359; found, 354.1365. General behavior of electrophilic and nucleophilic substitution reactions of pyrimidines. Our previous results. Reagents and conditions: i: NaNO2 (1.2 equiv), AcOH, rt; 1a,2a: R = H; R1 = Me; 1b,2b: R = H; R1 = Bn; 1c,2c: R = H; R1 = Bu; 1d,2d: R = Me
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Published 06 Sep 2013

Computational study of the rate constants and free energies of intramolecular radical addition to substituted anilines

  • Andreas Gansäuer,
  • Meriam Seddiqzai,
  • Tobias Dahmen,
  • Rebecca Sure and
  • Stefan Grimme

Beilstein J. Org. Chem. 2013, 9, 1620–1629, doi:10.3762/bjoc.9.185

Graphical Abstract
  • intermolecular or intramolecular manner have been employed in some transformations that are highly useful. Prominent examples are the Minisci reaction [11][12][13][14][15] for the preparation of mainly nitrogen heterocycles and Zard’s homolytic substitution reactions at nitrogen heterocycles with xanthates as
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Published 08 Aug 2013

Homolytic substitution at phosphorus for C–P bond formation in organic synthesis

  • Hideki Yorimitsu

Beilstein J. Org. Chem. 2013, 9, 1269–1277, doi:10.3762/bjoc.9.143

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  • substitution reactions of organic halides and related compounds with phosphination agents have now been rapidly developing since 2006. Yorimitsu and Oshima invented radical phosphination of organic halides with tetraphenyldiphosphine (Table 6) [43]. Tetraphenyldiphosphine is generated in situ by radical
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Published 28 Jun 2013

Titanium-mediated reductive cross-coupling reactions of imines with terminal alkynes: An efficient route for the synthesis of stereodefined allylic amines

  • Kebin Mao,
  • Guoqin Fan,
  • Yuanhong Liu,
  • Shi Li,
  • Xu You and
  • Dan Liu

Beilstein J. Org. Chem. 2013, 9, 621–627, doi:10.3762/bjoc.9.69

Graphical Abstract
  • substitution reactions [8][9], radical reactions [10] and Pd-catalyzed reactions [11]. Thus, allylic amines have been used for the synthesis of numerous heterocycles and bioactive amines, such as α- and β-amino acids [12][13][14][15], different alkaloids [16], aminoallylsilanes [17], aminoepoxides [18
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Published 27 Mar 2013

Kinetics and mechanism of the anilinolysis of aryl phenyl isothiocyanophosphates in acetonitrile

  • Hasi Rani Barai and
  • Hai Whang Lee

Beilstein J. Org. Chem. 2013, 9, 615–620, doi:10.3762/bjoc.9.68

Graphical Abstract
  • . Keywords: anilinolysis; cross-interaction constant; deuterium kinetic isotope effects; phosphoryl transfer reaction; reactive intermediates; Y-aryl phenyl isothiocyanophosphates; Introduction The nucleophilic substitution reactions of tetracoordinate phosphorus have been studied extensively
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Published 26 Mar 2013

Efficient Cu-catalyzed base-free C–S coupling under conventional and microwave heating. A simple access to S-heterocycles and sulfides

  • Silvia M. Soria-Castro and
  • Alicia B. Peñéñory

Beilstein J. Org. Chem. 2013, 9, 467–475, doi:10.3762/bjoc.9.50

Graphical Abstract
  • substitution reactions with methyl iodide and benzyl bromide, methyl phenyl sulfide and benzyl methyl sulfide in 81% and 66% yields, respectively, and 4-anisyl phenyl sulfide (4-AnSPh) in 85% yield (quantified by 1H NMR) by a second copper-catalyzed reaction (Scheme 8). Conclusion We have developed a simple
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Published 04 Mar 2013

Polymerization of novel methacrylated anthraquinone dyes

  • Christian Dollendorf,
  • Susanne Katharina Kreth,
  • Soo Whan Choi and
  • Helmut Ritter

Beilstein J. Org. Chem. 2013, 9, 453–459, doi:10.3762/bjoc.9.48

Graphical Abstract
  • anthraquinone dyes has been synthesized by nucleophilic aromatic substitution reactions and subsequent methacrylation. Thereby, green 5,8-bis(4-(2-methacryloxyethyl)phenylamino)-1,4-dihydroxyanthraquinone (2), blue 1,4-bis(4-((2-methacryloxyethyl)oxy)phenylamino)anthraquinone (6) and red 1-((2-methacryloxy-1,1
  • materials used for iris implants or other medical applications. Conclusion In conclusion, a series of novel anthraquinone based polymerizable dyes has been synthesized by nucleophilic aromatic substitution reactions of anthraquinone derivatives with several amino alcohols. Depending on the moieties that
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Published 28 Feb 2013

Radical zinc-atom-transfer-based carbozincation of haloalkynes with dialkylzincs

  • Fabrice Chemla,
  • Florian Dulong,
  • Franck Ferreira and
  • Alejandro Pérez-Luna

Beilstein J. Org. Chem. 2013, 9, 236–245, doi:10.3762/bjoc.9.28

Graphical Abstract
  • organometallic nucleophiles and undergo intramolecular nucleophilic substitution reactions [47][48][49][50][51]. Experimental Experiments involving organometallic compounds were carried out in dried glassware under a positive pressure of dry Ar. All solvents were distilled to remove stabilizers and dried with a
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Published 04 Feb 2013

Chemistry of polyhalogenated nitrobutadienes, 10: Synthesis of highly functionalized heterocycles with a rigid 6-amino-3-azabicyclo[3.1.0]hexane moiety

  • Viktor A. Zapol’skii,
  • Jan C. Namyslo,
  • Armin de Meijere and
  • Dieter E. Kaufmann

Beilstein J. Org. Chem. 2012, 8, 621–628, doi:10.3762/bjoc.8.69

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  • Göttingen, Germany 10.3762/bjoc.8.69 Abstract The nitropolychlorobutadienes 3, 4 are valuable building blocks for various amination and successive heterocyclization products. Nucleophilic substitution reactions of the partially protected, bioactive amines 1, 2 with either vinyl, imidoyl or carbonyl
  • nucleophilic substitution reactions as described above, it was of interest to incorporate a persubstituted diene unit as in 3 and 4 into a heterocycle. For example, the isothiazole 17 was obtained from the nitrodiene 3 upon treatment with elemental sulfur at 200 °C [23]. Subsequent reaction with fuming nitric
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Published 23 Apr 2012

Carbamate-directed benzylic lithiation for the diastereo- and enantioselective synthesis of diaryl ether atropisomers

  • Abigail Page and
  • Jonathan Clayden

Beilstein J. Org. Chem. 2011, 7, 1327–1333, doi:10.3762/bjoc.7.156

Graphical Abstract
  • stereochemical course of the lithiation–substitution reactions have been elucidated, and further work remains to exploit this transformation for the potential synthesis of new classes of chiral ligands [12]. Desymmetrising metallation for the enantioselective synthesis of atropisomers. Benzylic lithiation of a
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Published 26 Sep 2011

A practical two-step procedure for the preparation of enantiopure pyridines: Multicomponent reactions of alkoxyallenes, nitriles and carboxylic acids followed by a cyclocondensation reaction

  • Christian Eidamshaus,
  • Roopender Kumar,
  • Mrinal K. Bera and
  • Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2011, 7, 962–975, doi:10.3762/bjoc.7.108

Graphical Abstract
  • and enones, as well as in palladium-catalyzed allylic substitution reactions [14][15][16][17][18][19][20]. Thus, the synthesis of specifically functionalized pyridines is of considerable interest, and many approaches toward this heterocyclic structure have been disclosed in the literature [21]. In
  • nucleophilic substitution reactions. Conclusion We have demonstrated that enantiopure functionalized carboxylic acids and nitriles can be used without problems in our previously reported pyridine synthesis. The starting materials were successfully transformed into the corresponding pyridines without loss of
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Published 13 Jul 2011

Gold-catalyzed propargylic substitutions: Scope and synthetic developments

  • Olivier Debleds,
  • Eric Gayon,
  • Emmanuel Vrancken and
  • Jean-Marc Campagne

Beilstein J. Org. Chem. 2011, 7, 866–877, doi:10.3762/bjoc.7.99

Graphical Abstract
  • the field of nucleophilic substitution reactions, leaving groups are mostly often obtained from alcohols but initially require their transformation to better leaving groups such as sulfonates or acetates. For economic, environmental and practical reasons it is therefore of interest to develop new
  • substitution reactions. BF3 vs AuCl3 in propargylic substitutions [25]. The use of bis-nucleophiles in direct propargylic substitutions. Tandem reactions from protected hydroxylamines and propargylic alcohols. P = Cbz, PhSO2. Tentative hydrolysis of bis-adduct 24a. Iron-catalyzed propargylic substitutions
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Published 28 Jun 2011

Gold-catalyzed alkylation of silyl enol ethers with ortho-alkynylbenzoic acid esters

  • Haruo Aikawa,
  • Tetsuro Kaneko,
  • Naoki Asao and
  • Yoshinori Yamamoto

Beilstein J. Org. Chem. 2011, 7, 648–652, doi:10.3762/bjoc.7.76

Graphical Abstract
  • complex 8 as a leaving compound [43][44][45][46]. In the case of ordinary substitution reactions with alkyl halides (path a in Scheme 1), generated halide ions would attack the silyl group, due to their strong affinities with the silicon atom, and cleave the silicon–oxygen bond of 7. However, in the
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Published 20 May 2011

Asymmetric synthesis of tertiary thiols and thioethers

  • Jonathan Clayden and
  • Paul MacLellan

Beilstein J. Org. Chem. 2011, 7, 582–595, doi:10.3762/bjoc.7.68

Graphical Abstract
  • preparation are abundant, and usually rely on stereospecific substitution reactions [9]. These reactions are well suited to the construction of secondary thiol derivatives. By contrast, few methods are suitable for the asymmetric preparation of simple tertiary thiols 1. While the asymmetric synthesis of
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Published 10 May 2011

One-pot gold-catalyzed synthesis of 3-silylethynyl indoles from unprotected o-alkynylanilines

  • Jonathan P. Brand,
  • Clara Chevalley and
  • Jérôme Waser

Beilstein J. Org. Chem. 2011, 7, 565–569, doi:10.3762/bjoc.7.65

Graphical Abstract
  • layers were combined and extracted with Et2O (20 mL). The organic layers were combined, washed successively with saturated NaHCO3 (20 mL) and brine (20 mL), dried with MgSO4 and concentrated under reduced pressure. The crude product was purified by flash chromatography. Domino cyclization–substitution
  • reactions of 2-alkynylanilines. Gold-catalyzed direct alkynylation of indoles with TIPS-EBX (1). One-pot alkynylaniline cyclization/direct alkynylation. Synthesis of 2-alkynylanilines 2. Domino cyclization–alkynylation of aniline 2a. Scope of the reaction. Supporting Information Supporting Information File
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Published 04 May 2011

The arene–alkene photocycloaddition

  • Ursula Streit and
  • Christian G. Bochet

Beilstein J. Org. Chem. 2011, 7, 525–542, doi:10.3762/bjoc.7.61

Graphical Abstract
  • enthalpy of the radical ion pair formation, ΔEexcit = excitation energy of the chromophore, ΔEcoul = coulomb interaction energy of the radical ions and = half wave potential of donor and acceptor. If electron transfer pathways dominate, substitution reactions are found to prevail. However, if the electron
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Published 28 Apr 2011

An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

  • Marcus Baumann,
  • Ian R. Baxendale,
  • Steven V. Ley and
  • Nikzad Nikbin

Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57

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Published 18 Apr 2011
Graphical Abstract
  • , the sensitization by acetone solvent appears to be more practical as it allows the handling of larger scales. The general catalytic ability of the dibenzosemibullvalene salt 3d in phase-transfer catalyzed nucleophilic substitution reactions was investigated. Compounds 5 [21], 7, 9, and 11 were chosen
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Published 26 Jan 2011

Highly substituted benzannulated cyclooctanol derivatives by samarium diiodide-induced cyclizations

  • Jakub Saadi,
  • Irene Brüdgam and
  • Hans-Ulrich Reissig

Beilstein J. Org. Chem. 2010, 6, 1229–1245, doi:10.3762/bjoc.6.141

Graphical Abstract
  • ][7][8][9][10][11][12][13][14][15][16][17][18]. Successful approaches include ring-closing metathesis [4], rearrangements [5], and cycloadditions [6], transition metal-catalyzed cyclizations [7][8], nucleophilic and electrophilic substitution reactions [9] as well as ring expansion reactions [10
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Published 28 Dec 2010

Physical organic chemistry

  • John A. Murphy

Beilstein J. Org. Chem. 2010, 6, 1025–1025, doi:10.3762/bjoc.6.116

Graphical Abstract
  • knowledge of mechanism of fundamental aliphatic substitution reactions, among others, was enormous, but our knowledge of reactivity and mechanism has continued to progress and deepen enormously ever since and this has been reflected in a number of Nobel Prizes in Chemistry. In an area of particular interest
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Published 03 Nov 2010

Chromo- and fluorophoric water-soluble polymers and silica particles by nucleophilic substitution reaction of poly(vinyl amine)

  • Katja Hofmann,
  • Ingolf Kahle,
  • Frank Simon and
  • Stefan Spange

Beilstein J. Org. Chem. 2010, 6, No. 79, doi:10.3762/bjoc.6.79

Graphical Abstract
  • with nitrogen-, oxygen-, or sulfur-containing nucleophiles by nucleophilic aromatic substitution reactions (SNArH) [32][33][34][35][36]. The reaction of 1 with 3-thiopropionic acid has used to produce a fluorescent sensor for cys/Hcy with a 75-fold fluorescence enhancement [34]. The SNArH reaction of 1
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Published 22 Jul 2010

9,10-Dioxa-1,2-diaza-anthracene derivatives from tetrafluoropyridazine

  • Graham Pattison,
  • Graham Sandford,
  • Dmitrii S. Yufit,
  • Judith A. K. Howard,
  • John A. Christopher and
  • David D. Miller

Beilstein J. Org. Chem. 2010, 6, No. 45, doi:10.3762/bjoc.6.45

Graphical Abstract
  • phenoxide, to give intermediate 5a. At this point, we would expect cyclisation to occur at position 5 to give product 6, again by analogy to the outcome of reaction between 3 and excess phenoxide. However, since nucleophilic aromatic substitution reactions are frequently reversible [13], conversion of 6
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Published 06 May 2010

Comparison of zwitterionic N-alkylaminomethanesulfonic acids to related compounds in the Good buffer series

  • Robert D. Long,
  • Newton P. Hilliard Jr,
  • Suneel A. Chhatre,
  • Tatiana V. Timofeeva,
  • Andrey A. Yakovenko,
  • Daniel K. Dei and
  • Enoch A. Mensah

Beilstein J. Org. Chem. 2010, 6, No. 31, doi:10.3762/bjoc.6.31

Graphical Abstract
  • indicated that there were some prior reports of the lack of reactivity of chloro- and bromomethanesulfonic acids (and related derivatives) in nucleophilic substitution reactions, especially those with weaker nucleophiles such as amines [6][7][8]. We therefore abandoned this route in favor of a different
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Published 01 Apr 2010
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