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Search for "carbocyclic" in Full Text gives 105 result(s) in Beilstein Journal of Organic Chemistry.

Fused bicyclic piperidines and dihydropyridines by dearomatising cyclisation of the enolates of nicotinyl-substituted esters and ketones

  • Heloise Brice,
  • Jonathan Clayden and
  • Stuart D. Hamilton

Beilstein J. Org. Chem. 2010, 6, No. 22, doi:10.3762/bjoc.6.22

Graphical Abstract
  • carbocyclic ring by dearomatising cyclisation The study was initiated with the synthesis of the δ-nicotinyl ketone 7 as illustrated in Scheme 2. Ethyl benzoylacetate was alkylated with 3-(3-iodopropyl)pyridine 5 and the product 6 hydrolysed and decarboxylated to yield the pyridine 7 in moderate yield. On
  • corresponding 12.9 Hz coupling to the proton α to the ester group is consistent with adoption of an exo–equatorial orientation by this substituent. Formation of a tetrahydrofuran by dearomatising cyclisation Encouraged by the successful formation of carbocyclic rings in dearomatising cyclisations of nicotinyl
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Published 02 Mar 2010

Ring-alkyl connecting group effect on mesogenic properties of p-carborane derivatives and their hydrocarbon analogues

  • Aleksandra Jankowiak,
  • Piotr Kaszynski,
  • William R. Tilford,
  • Kiminori Ohta,
  • Adam Januszko,
  • Takashi Nagamine and
  • Yasuyuki Endo

Beilstein J. Org. Chem. 2009, 5, No. 83, doi:10.3762/bjoc.5.83

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  • B) than for carbocyclic derivatives (C and D). Analysis indicates that this effect may have quadrupolar and conformational origin. Keywords: p-carborane; liquid crystals; structure-property relationship; Introduction During the past decade, we have been investigating mesogenic derivatives of p
  • exclusively the nematic phase. Similar nematic behavior is observed for carbocycles in series 17–20 with the exception of 19D, which exhibits a SmA phase in addition to a N phase. In contrast, most carbocyclic derivatives in series 14[6]–16[6] display only smectic and soft crystalline polymorphs. The bicyclo
  • alkoxyphenyl group) for the carbocyclic compounds. In contrast, the difference in TNI is larger by 10 K for p-carborane A and 18 K for p-carborane B (Figure 5 and Figure 6). These results are consistent with earlier findings for pairs 1/2, 3/4, and 5/6 (Figure 5) in which a particularly large impact of the
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Published 30 Dec 2009

Synthesis of chiral cyclohexanes and carbasugars by 6-exo-dig radical cyclisation reactions

  • Rajeev K. Shrivastava,
  • Elise Maudru,
  • Gurdial Singh,
  • Richard H. Wightman and
  • Keith M. Morgan

Beilstein J. Org. Chem. 2008, 4, No. 43, doi:10.3762/bjoc.4.43

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  • of carbohydrates as precursors for highly functionalised carbocyclic rings systems has found wide utility in organic synthesis [1][2][3][4][5][6][7][8][9][10][11]. In particular there is a large amount of literature devoted to the synthesis of cyclopentanes [12][13] that employs a 5-exo-dig ring
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Published 19 Nov 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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  • , Shanghai 201620, China 10.3762/bjoc.4.18 Abstract We present a mechanistic investigation of Pd-catalyzed allylic substitution of cyclic gem-difluorinated carbonates 1 and 4, previously employed in the synthesis of 3',3'-difluoro-2'-hydroxymethyl-4',5'-unsaturated carbocyclic nucleosides in 17 steps. The
  • substitution features a reversal of regioselectivity caused by fluorine. Background Carbocyclic nucleosides (CNAs), in which the furanose oxygen atoms of the 4'-oxonucleosides are substituted by CH2, have received considerable attention because they exhibit greater metabolic stability toward nucleoside
  • phosphorylases and higher lipophilicity, two properties that are potentially beneficial in terms of increased in vivo half life, oral efficiency and cell wall penetration [1][2]. Based on CNA skeletons, 1,2-disubstituted carbocyclic nucleosides (OTCs) recently attracted more and more attention [3][4][5][6][7][8
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Published 27 May 2008

Allylsilanes in the synthesis of three to seven membered rings: the silylcuprate strategy

  • Asunción Barbero,
  • Francisco J. Pulido and
  • M. Carmen Sañudo

Beilstein J. Org. Chem. 2007, 3, No. 16, doi:10.1186/1860-5397-3-16

Graphical Abstract
  • to a wide range of functionalised allylsilanes, which are valuable intermediates for carbocyclic annulations. Effectively, the former substrates (containing a nucleophilic allylsilane unit and an electrophilic function) undergo "intramolecular allylsilane terminated" cyclizations when treated with
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Published 22 May 2007
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