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Search for "substitution reactions" in Full Text gives 135 result(s) in Beilstein Journal of Organic Chemistry.

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

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  • 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

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  • 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

Highly brominated anthracenes as precursors for the convenient synthesis of 2,9,10-trisubstituted anthracene derivatives

  • Osman Cakmak,
  • Leyla Aydogan,
  • Kiymet Berkil,
  • Ilhami Gulcin and
  • Orhan Buyukgungor

Beilstein J. Org. Chem. 2008, 4, No. 50, doi:10.3762/bjoc.4.50

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  • tribromide 12 was transformed to trimethoxy compound 13 and trinitrile 14 by copper-assisted nucleophilic substitution reactions. Keywords: anthracene derivative; bromination; bromoanthracene; cyanoanthracene; methoxyanthracene; Introduction Anthracene derivatives have been extensively investigated in many
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Published 10 Dec 2008

Understanding the mechanism of Pd-catalyzed allylic substitution of the cyclic difluorinated carbonates

  • Jun Xu,
  • Xiao-Long Qiu and
  • Feng-Ling Qing

Beilstein J. Org. Chem. 2008, 4, No. 18, doi:10.3762/bjoc.4.18

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  • Pd-catalyzed allylic substitution reactions. X-ray structure of trans-trans dimer 8. Pd-catalyzed allylic substitution of the gem-difluorinated allylic carbonates 1 and 4. Synthesis of trans-trans dimer 8 and syn-syn dimer 9. Reaction of trans-trans dimer 8 with 3-benzoylthymine sodium / PPh3
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Published 27 May 2008

Synthesis of the Benzo- fused Indolizidine Alkaloid Mimics

  • Daniel L. Comins and
  • Kazuhiro Higuchi

Beilstein J. Org. Chem. 2007, 3, No. 42, doi:10.1186/1860-5397-3-42

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  • indolizidine alkaloid mimics has been developed. The indolizidine derivatives 8 were prepared via heteroaryl Grignard addition to N-acylpyridinium salts followed by an intramolecular Heck cyclization. Further substitution reactions were developed to demonstrate that heterocycles 8 are good scaffolds for
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Published 30 Nov 2007

Single and double stereoselective fluorination of (E)-allylsilanes

  • Marcin Sawicki,
  • Angela Kwok,
  • Matthew Tredwell and
  • Véronique Gouverneur

Beilstein J. Org. Chem. 2007, 3, No. 34, doi:10.1186/1860-5397-3-34

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  • ). When a second stereogenic centre is present on the starting (E)-allylsilane, up to four stereoisomers may be formed upon fluorination. This is illustrated in Scheme 1 with the fluorodesilylation of anti (E)-1e. For substitution reactions (SE2') of allylsilanes such as anti (E)-1e, with electrophiles
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Preliminary Communication
Published 25 Oct 2007

Expedient syntheses of the N-heterocyclic carbene precursor imidazolium salts IPr·HCl, IMes·HCl and IXy·HCl

  • Lukas Hintermann

Beilstein J. Org. Chem. 2007, 3, No. 22, doi:10.1186/1860-5397-3-22

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  • them from participating as electrophiles in aromatic substitution reactions. Conclusion The useful imidazolium salts IPr·HCl (1), IMes·HCl (2) and IXy·HCl (3) have previously been synthesized by a range of methods giving the products in variable purity and yields. We now present a protocol for the
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Published 28 Aug 2007

Pd-catalysed [3 + 3] annelations in the stereoselective synthesis of indolizidines

  • Olivier Y. Provoost,
  • Andrew J. Hazelwood and
  • Joseph P. A. Harrity

Beilstein J. Org. Chem. 2007, 3, No. 8, doi:10.1186/1860-5397-3-8

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  • reasons for this difference in catalyst activity are unclear at present, we speculate that n-BuLi may be responsible for the formation of hitherto uncharacterised phosphine ligands BunP(OiPr)3-n that promote the annelation over simple P(OiPr)3. Indeed, analogous alkoxide substitution reactions of
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Preliminary Communication
Published 08 Feb 2007

Efficient synthesis of 5-substituted 2-aryl- 6-cyanoindolizines via nucleophilic substitution reactions

  • Eugene V. Babaev,
  • Natalya I. Vasilevich and
  • Anna S. Ivushkina

Beilstein J. Org. Chem. 2005, 1, No. 9, doi:10.1186/1860-5397-1-9

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  • – 8.11 ppm. The halogen atom in 5-chloro-6-cyanoindolizines 2 should be activated to nucleophilic substitution reactions by the suitable ortho-arrangement of the nitrogen atom of the pyridine ring and electron-withdrawing cyano-group. The pattern strongly resembled 2-chloro-3-cyanopyridine, that is why
  • obtain 2-aryl-5-chloro-6-cyano-7-methylindolizines from 2-aryl-6-cyano-7-methyl-5-indolizinones and to prove the possibility to employ them in nucleophilic substitution reactions. Moreover, these reactions are the first examples of preparative nucleophilic substitution in indolizines, and our findings
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Preliminary Communication
Published 07 Oct 2005
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