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Search for "dihydrofuran" in Full Text gives 56 result(s) in Beilstein Journal of Organic Chemistry.

Light-induced olefin metathesis

  • Yuval Vidavsky and
  • N. Gabriel Lemcoff

Beilstein J. Org. Chem. 2010, 6, 1106–1119, doi:10.3762/bjoc.6.127

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  • Hg lamp at 300 nm for 30 min at room temperature, followed by heating at 80 °C until completion of the reaction. The reaction time, compared to the non-irradiated control experiment, was reduced six fold. The various dihydrofuran rings obtained by this method are shown in Figure 7 along with their
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Published 23 Nov 2010

Redox-active tetrathiafulvalene and dithiolene compounds derived from allylic 1,4-diol rearrangement products of disubstituted 1,3-dithiole derivatives

  • Filipe Vilela,
  • Peter J. Skabara,
  • Christopher R. Mason,
  • Thomas D. J. Westgate,
  • Asun Luquin,
  • Simon J. Coles and
  • Michael B. Hursthouse

Beilstein J. Org. Chem. 2010, 6, 1002–1014, doi:10.3762/bjoc.6.113

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  • the discovery of an unexpected rearrangement of 4,5-bis(2-arylhydroxymethyl)-1,3-dithiole-2-thiones (2) in the presence of acid catalysts [4]. As well as the expected dihydrofuran, formed by a nucleophilic ring-closing reaction, other compounds were also produced depending on the nature of the aryl
  • obtained as the major product (by tlc). By contrast, when 2 was treated with HBr in CH2Cl2, compound 7 was isolated as a yellow oil via the initially produced dihydrofuran 4 along with compound 8 (observed only by 1H NMR) [6]. The behaviour of 4,5-bis(2-thienylhydroxymethyl)-1,3-dithiole-2-thione in the
  • of spirocyclopropyl benzenium species [14]. However, as seen in Scheme 3, we propose a methoxy stabilised spirocyclopentyl benzenium intermediate. This mechanism is only valid for the 4-methoxy derivative as the position of the electron donating groups is fundamental in producing the dihydrofuran or
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Published 21 Oct 2010
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  • ether, dihydropyran, and dihydrofuran, all added smoothly to glyceraldehyde-derived nitrones 2a or 2b after lithiation with tert-butyllithium. Whereas in the reaction with uncomplexed nitrones, 1.5 equivalents of the respective lithiated enol ether were sufficient to obtain the desired syn-products with
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Published 09 Jul 2010

Recent progress on the total synthesis of acetogenins from Annonaceae

  • Nianguang Li,
  • Zhihao Shi,
  • Yuping Tang,
  • Jianwei Chen and
  • Xiang Li

Beilstein J. Org. Chem. 2008, 4, No. 48, doi:10.3762/bjoc.4.48

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  • of 67 to 1,3-dimesitylimidazol-2-ylidene ruthenium benzylidene catalyst (RuCl2(=C(H)-Ph)(PCy3)(IMes)) after protection of the free hydroxyl group afforded the RCM product 68. Hydrogenation of the double bond of dihydrofuran 68 and iodination of the primary alcohol gave 69, which was then utilized to
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Published 05 Dec 2008

One-pot preparation of substituted pyrroles from α-diazocarbonyl compounds

  • Fernando de C. da Silva,
  • Mauricio G. Fonseca,
  • Renata de S. Rianelli,
  • Anna C. Cunha,
  • Maria C. B. V. de Souza and
  • Vitor F. Ferreira

Beilstein J. Org. Chem. 2008, 4, No. 45, doi:10.3762/bjoc.4.45

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  • Abstract In this work an efficient one-pot synthesis of substituted pyrroles 7a–n is described, which involves the in situ formation of dihydrofurans ethyl 5-butoxy-2-methyl-4,5-dihydrofuran-3-carboxylate (4), 1-(5-butoxy-2-methyl-4,5-dihydrofuran-3-yl)ethanone (5) and 5-butoxy-4,5-dihydrofuran-3
  • -carbaldehyde (6) followed by reaction with primary amines. Keywords: diazocarbonyl; dihydrofuran; one-pot synthesis; pyrrole; Introduction The pyrrole unit [1] occurs in many interesting classes of compounds such as pharmaceutical agents [2][3][4][5], conducting polymers [6][7], molecular optics [8][9][10
  • variations in the reaction times (see Table 1). The reaction of the dihydrofuran intermediates 4, 5 and 6 with excess of primary amines in the presence of glacial acetic acid afforded the corresponding substituted pyrroles 7a–n in moderate to good yields (Table 1). Slightly different reactivity between 4, 5
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Published 28 Nov 2008

An efficient synthesis of novel pyrano[2,3-d]- and furopyrano[2,3-d]pyrimidines via indium- catalyzed multi- component domino reaction

  • Dipak Prajapati and
  • Mukut Gohain

Beilstein J. Org. Chem. 2006, 2, No. 11, doi:10.1186/1860-5397-2-11

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  • Knoevenagel/hetero-Diels-Alder reaction of 1,3-dimethyl barbituric acid with an aromatic aldehyde and ethyl vinyl ether/2,3-dihydrofuran in presence of 1 mol% of indium(III) chloride. The reaction also proceeds in aqueous media without using any catalyst, but the yield is comparatively less (65–70
  • reaction of α,β-ethylenic ketones and ethyl vinyl ether or 2,3-dihydrofuran has remained unexplored.[11] Herein, we report the first example of indium(III) chloride catalysed synthesis of fused pyrimidine derivatives via a multicomponent domino Knoevenagel hetero Diels-Alder reaction. The reaction proceeds
  • ], we have investigated a new, simple and efficient synthesis of novel fused pyrimidines based on inverse electron-demand Diels-Alder reaction using ethyl vinyl ether/dihydrofuran and α,β-ethylenic ketones formed in situ as heterodienes in presence of 1 mol% of indium(III) trichloride (Scheme 1). This
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Published 13 Jun 2006
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