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Search for "thioether" in Full Text gives 109 result(s) in Beilstein Journal of Organic Chemistry.

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
  • products 16 with complete inversion of configuration [16][17]. Acid catalysed cleavage of a thioether or thioacetate yields tert-thiols 17 in good yield. 1.1.2 Epoxide ring opening SN2 displacements from quaternary electrophiles require specific structural features to avoid competing racemisation
  • of the leaving group with a 1,4-benzoquinone derivative, DBBQ (35) being most effective (Scheme 12). Addition of a thiol nucleophile to adduct 32 results in SN2 inversion and isolation of the enantiomerically pure (94:6–99:1 er) tertiary thioether 33 and by-product 34. Highest yields were obtained
  • with BtzSH (36) and BoxSH (37). The reaction proceeds well with many hindered substrates incorporating aromatic, alkyl and ester substituents with excellent stereospecificity. Enantiomerically pure thiols can also be made from the product: Aromatic thioether 38 is reduced with lithium aluminium hydride
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Published 10 May 2011

Kinetic evaluation of the solvolysis of isobutyl chloro- and chlorothioformate esters

  • Malcolm J. D’Souza,
  • Matthew J. McAneny,
  • Dennis N. Kevill,
  • Jin Burm Kyong and
  • Song Hee Choi

Beilstein J. Org. Chem. 2011, 7, 543–552, doi:10.3762/bjoc.7.62

Graphical Abstract
  • enzyme elastase [66]. In Figure 1, the 3-D images of isobutyl chloroformate (1') and isobutyl chlorothioformate (2') are presented. In these figures, it is clear that the isopropyl group is pushed out of the plane due the presence of a carbon atom next to the ether or thioether atom in 1' and 2'. This
  • 25.0 °C. In pure methanol and ethanol a dominant association–dissociation (addition–elimination) mechanism, with rate-limiting addition, is believed to be effective in all four substrates. This rate order indicates that the inductive ability of the alkyl thioether group is almost independent of the
  • resonance-stabilized carbocation intermediate is more efficient for isopropyl chlorothioformate (5) when compared to 2, as the presence of the additional carbon pushes the isopropyl group out of the plane of the thioether atom in 2' (Figure 1). This opinion is supported by an increase seen in the l/m ratio
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Published 29 Apr 2011

Photoinduced electron-transfer chemistry of the bielectrophoric N-phthaloyl derivatives of the amino acids tyrosine, histidine and tryptophan

  • Axel G. Griesbeck,
  • Jörg Neudörfl and
  • Alan de Kiff

Beilstein J. Org. Chem. 2011, 7, 518–524, doi:10.3762/bjoc.7.60

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  •  1). For example, the glutamic acid derivative 3 resulted in the formation of a diastereoisomeric mixture of benzopyrrolizidinones 4 [6]. For a specific system, N-phthaloyl methionine (5), we have detected bielectrophoric behavior in that the electron transfer from the thioether group competes
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Published 26 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

Graphical Abstract
  • esomeprazole the subsequent steps involve an S-alkylation as well as an asymmetric oxidation of the newly formed thioether [59][60]. Additional structural diversity in the aniline component can be introduced by protection, nitration, deprotection and reduction of the starting amine compound 201. Scheme 40 for
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Published 18 Apr 2011

Aromatic and heterocyclic perfluoroalkyl sulfides. Methods of preparation

  • Vladimir N. Boiko

Beilstein J. Org. Chem. 2010, 6, 880–921, doi:10.3762/bjoc.6.88

Graphical Abstract
  • carbanion (RF−) in turn reacted with the sulfenyl iodide to generate a thioether. However, RFCH3 and RFH, are also obtained as by-products, which may be a result of homolytic decomposition of the perfluoroalkyl iodides at high temperature [130][131]. Similarly, reactions of RFI with sodium thiophenoxide
  • , CF3I is a poorer electrophile than C3F7I - even under biphasic conditions. 4.1.4. Interaction of thiols with perfluoroalkyl bromides Although brominated perfluoroalkanes are cheaper and more readily available than the corresponding iodides, they react more slowly in thioether forming reactions. In
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Published 18 Aug 2010

Kinetic studies and predictions on the hydrolysis and aminolysis of esters of 2-S-phosphorylacetates

  • Milena Trmčić and
  • David R. W. Hodgson

Beilstein J. Org. Chem. 2010, 6, 732–741, doi:10.3762/bjoc.6.87

Graphical Abstract
  • k0 = 1.8 × 10−3 min−1 and 1.1 × 10−3 min−1, respectively with other 2-substituted acetates may provide insight at this point. Holmquist and Bruice have studied the hydrolysis kinetics of 2-nitrophenyl 2-(ethylthio)acetate at 30 °C [10], which is a thioether as opposed to the S-bridging-thiophosphates
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Published 16 Aug 2010

Molecular recognition of organic ammonium ions in solution using synthetic receptors

  • Andreas Späth and
  • Burkhard König

Beilstein J. Org. Chem. 2010, 6, No. 32, doi:10.3762/bjoc.6.32

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Published 06 Apr 2010

Synthesis of methylenebisamides using CC- or DCMT- activated DMSO

  • Qiang Wang,
  • Lili Sun,
  • Yu Jiang and
  • Chunbao Li

Beilstein J. Org. Chem. 2008, 4, No. 51, doi:10.3762/bjoc.4.51

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  • the attack of the amide on the sulfonium ion 1. When the reaction is carried out in toluene, intermediate 1 decomposes into intermediate 2. Thioether 3 is formed by the addition of the amide to intermediate 2. N-(Methylthiomethyl)octanamide (40% yield) was isolated when octanamide was treated with
  • DCMT in DMSO. Similarly, N-(1-(methylthio)-2-oxo-2-phenylethyl)benzamide (30% yield) was isolated when benzamide reacted with DCMT and 2-(methylsulfinyl)-1-phenylethanone. Thioether 3 is a good nucleophile and capable to substitute the chloride of CC or DCMT to generate sulfonium salt 5. The amide
  • substitutes the thioether of 5 to form methylenebisamides 6. Conclusion In conclusion, we have developed a simple and efficient procedure to produce methylenebisamides in good yield via the reaction of amides with CC- or DCMT-activated DMSO. The procedure reported herein is operationally simple, and requires
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Published 15 Dec 2008

Synthesis of 2-substituted 9-oxa-guanines {5-aminooxazolo[5,4-d]pyrimidin- 7(6H)-ones} and 9-oxa-2-thio- xanthines {5-mercaptooxazolo[5,4-d]pyrimidin- 7(6H)-ones}

  • Subrata Mandal,
  • Wen Tai Li,
  • Yan Bai,
  • Jon D. Robertus and
  • Sean M. Kerwin

Beilstein J. Org. Chem. 2008, 4, No. 26, doi:10.3762/bjoc.4.26

Graphical Abstract
  • commensurate with groups attached to sulfur (e.g., for 8a: 2.2 ppm in 1H and 13 ppm in 13C NMR, respectively) than to nitrogen, as would be the case for 4- or 3-alkylated 5-mercaptooxazolo[5,4-d]pyrimidine-7(6H)-ones. The thioether 8c bearing a propargyl substituent was subjected to “click” chemistry coupling
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Published 25 Jul 2008
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