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Search for "substitution reactions" in Full Text gives 143 result(s) in Beilstein Journal of Organic Chemistry.

Synthesis of 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene ligands and their application in regio- and enantioselective Pd-catalyzed allylic alkylation of monosubstituted allyl substrates

  • Zeng-Wei Lai,
  • Rong-Fei Yang,
  • Ke-Yin Ye,
  • Hongbin Sun and
  • Shu-Li You

Beilstein J. Org. Chem. 2014, 10, 1261–1266, doi:10.3762/bjoc.10.126

Graphical Abstract
  • . Preliminary explanation of the regioselectivity. Transition metal-catalyzed allylic substitution reactions with monosubstituted allyl substrates. Preparation of 1-[bis(trifluoromethyl)phosphine]-1’-oxazolinylferrocene ligands. Reagents and conditions: (a) (i) n-BuLi, TMEDA, Et2O, rt; (ii) (BrCF2)2, −78 °C. (b
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Published 30 May 2014

Syntheses of fluorooxindole and 2-fluoro-2-arylacetic acid derivatives from diethyl 2-fluoromalonate ester

  • Antal Harsanyi,
  • Graham Sandford,
  • Dmitri S. Yufit and
  • Judith A.K. Howard

Beilstein J. Org. Chem. 2014, 10, 1213–1219, doi:10.3762/bjoc.10.119

Graphical Abstract
  • ester is utilised as a building block for the synthesis of 2-fluoro-2-arylacetic acid and fluorooxindole derivatives by a strategy involving nucleophilic aromatic substitution reactions with ortho-fluoronitrobenzene substrates followed by decarboxylation, esterification and reductive cyclisation
  • elemental fluorine for the key construction of the carbon–fluorine bond by complementary direct selective direct fluorination [41][42][43][44], continuous flow [45][46][47][48][49] and building block [50] strategies, in this paper, we describe nucleophilic aromatic substitution reactions of carbanions
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Published 22 May 2014

Preparation of phosphines through C–P bond formation

  • Iris Wauters,
  • Wouter Debrouwer and
  • Christian V. Stevens

Beilstein J. Org. Chem. 2014, 10, 1064–1096, doi:10.3762/bjoc.10.106

Graphical Abstract
  • ; enantioselectivity; hydrophosphination; organophosphorus chemistry; phosphines; phosphine-boranes; substitution reactions; trivalent phosphorus; Introduction Phosphines are an important class of organophosphorus compounds. They are often used as ligands in metal complex catalysis and they have become a popular
  • C–C bond is more efficient than substitution reactions when considering atom efficiency, what makes it not only greener but also more economical. Other phosphination reactions of unsaturated bonds, such as diphosphination, thiophosphination or selenophosphination, were not included [67]. Depending
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Published 09 May 2014

On the mechanism of photocatalytic reactions with eosin Y

  • Michal Majek,
  • Fabiana Filace and
  • Axel Jacobi von Wangelin

Beilstein J. Org. Chem. 2014, 10, 981–989, doi:10.3762/bjoc.10.97

Graphical Abstract
  • different mechanisms in these aromatic substitution reactions with arene diazonium salts. The redox potentials of most substituted arene diazonium salts cluster with very little deviation around 0.0 V vs. SCE (±0.2 V) [23][24] so that the observed differences in Φ can be largely attributed to different
  • erosion of Φ. Conclusion In summary, we have investigated the impact of several reaction parameters on the outcome and mechanism of photocatalytic aromatic substitution reactions of arenediazonium salts in the presence of eosin Y. However, the significance of these data certainly extends to other light
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Published 30 Apr 2014

One-pot three-component synthesis and photophysical characteristics of novel triene merocyanines

  • Christian Muschelknautz,
  • Robin Visse,
  • Jan Nordmann and
  • Thomas J. J. Müller

Beilstein J. Org. Chem. 2014, 10, 599–612, doi:10.3762/bjoc.10.51

Graphical Abstract
  • been accessed by Knoevenagel condensations [12][13][14] or substitution reactions [15][16][17][18]. Still the quest for new synthetic strategies, novel substitution patterns, and eventually unusual properties and effects has become an ongoing challenge for organic synthesis, physical organic chemistry
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Published 05 Mar 2014

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

Graphical Abstract
  • lariat-type crown ethers employs sequences in which SET-promoted macrocyclization reactions of α-trialkylsilyl-terminated, polyethoxy-tethered phthalimides and naphthalimides are followed by a side chain introduction through substitution reactions at the amidol centers in the macrocyclic ethers. The
  • macrocyclization reactions of the α-trialkylsilyl-terminated, polyethoxy-tethered phthalimides and naphthalimides are followed by a side chain introduction through substitution reactions at the amidol centers in the macrocyclic ethers (Scheme 6). Direct approaches for the preparation of imide-derived lariat-type
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Published 27 Feb 2014

Diversity-oriented synthesis of dihydrobenzoxazepinones by coupling the Ugi multicomponent reaction with a Mitsunobu cyclization

  • Lisa Moni,
  • Luca Banfi,
  • Andrea Basso,
  • Alice Brambilla and
  • Renata Riva

Beilstein J. Org. Chem. 2014, 10, 209–212, doi:10.3762/bjoc.10.16

Graphical Abstract
  • heterocycles [1]. This is usually accomplished by introducing additional orthogonal functional groups in the starting components, taking advantage of the high tolerance of the U-4CR. In particular our group has been quite active in the last seven years in coupling the U-4CR with acyl or aliphatic substitution
  • reactions [2], especially the intramolecular Mitsunobu reaction of alcohols with phenols or sulfonamides. By exploiting a single post-MCR transformation (the Mitsunobu reaction) it is possible to obtain several diverse heterocyclic scaffolds by installing the two additional groups in any of the four
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Published 17 Jan 2014

Silica: An efficient catalyst for one-pot regioselective synthesis of dithioethers

  • Samir Kundu,
  • Babli Roy and
  • Basudeb Basu

Beilstein J. Org. Chem. 2014, 10, 26–33, doi:10.3762/bjoc.10.5

Graphical Abstract
  • products. Thus, moistened silica gel turns out to be effective for sequential substitution reactions, and entirely anti-Markovnikov addition, while pre-calcined dry silica gel could efficiently give rise to only Markovnikov addition products. The reactions over dry silica gel appear to be faster than the
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Published 07 Jan 2014

Flow microreactor synthesis in organo-fluorine chemistry

  • Hideki Amii,
  • Aiichiro Nagaki and
  • Jun-ichi Yoshida

Beilstein J. Org. Chem. 2013, 9, 2793–2802, doi:10.3762/bjoc.9.314

Graphical Abstract
  • by nucleophilic substitution reactions using [18F]-fluoride ion (Scheme 7) [55][56][57][58][59][60][61][62][63][64][65][66][67]. For not only fluorination/fluoroalkylation, but also for defluorination, flow microreactor synthesis is quite effective. Defluorination involving a nucleophilic addition
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Published 05 Dec 2013

Triol-promoted activation of C–F bonds: Amination of benzylic fluorides under highly concentrated conditions mediated by 1,1,1-tris(hydroxymethyl)propane

  • Pier Alexandre Champagne,
  • Alexandre Saint-Martin,
  • Mélina Drouin and
  • Jean-François Paquin

Beilstein J. Org. Chem. 2013, 9, 2451–2456, doi:10.3762/bjoc.9.283

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  • fluoride as a leaving group in nucleophilic substitution reactions of activated alkyl fluorides through hydrogen bonding [17]. Particularly, water was used as the hydrogen bond donor and co-solvent. DFT calculations show that activation proceeds through stabilization of the transition-state structure by
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Published 13 Nov 2013

An overview of the synthetic routes to the best selling drugs containing 6-membered heterocycles

  • Marcus Baumann and
  • Ian R. Baxendale

Beilstein J. Org. Chem. 2013, 9, 2265–2319, doi:10.3762/bjoc.9.265

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  • pyrimidines form very tight hydrogen-bonding arrays as seen in DNA and RNA. Synthetically, the electron-poor nature of pyrimidines accounts for the manifold functionalisation pathways using nucleophilic aromatic substitution chemistry. Electrophilic aromatic substitution reactions are more common during the
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Published 30 Oct 2013

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

Graphical Abstract
  • 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

Graphical Abstract
  • 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
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