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Search for "boronic acids" in Full Text gives 108 result(s) in Beilstein Journal of Organic Chemistry.

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  • acid derivatives 9a [16] and 9b (Scheme 2). The terpyridine moieties can be attached to the diarylethene unit by Suzuki type cross coupling of the diiodo switch 4 with the boronic esters 9a and 9b under conditions similar to those described for other aryl boronic acids and their derivatives to yield
  • after irradiation with vis light (dotted). UV–vis-spectra of [Zn2+@10a] before (solid), after UV-irradiation (dashed) and after irradiation with vis light (dotted). Synthesis of twofold iodinated bis(benzo[b]thiophenyl)perfluorocyclopentene 4. Synthesis of terpyridinyl boronic acids 9a and 9b. Synthesis
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Published 26 May 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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Review
Published 06 Apr 2010

Diastereoselective functionalisation of benzo-annulated bicyclic sultams: Application for the synthesis of cis-2,4-diarylpyrrolidines

  • Susan Kelleher,
  • Pierre-Yves Quesne and
  • Paul Evans

Beilstein J. Org. Chem. 2009, 5, No. 69, doi:10.3762/bjoc.5.69

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  • means of incorporating alternative structural features into our masked pyrrolidine ring. Under standard conditions, the reactivity of a series of commercially available aryl and alkenyl boronic acids with 24a was investigated. Pleasingly, it was found that in the case of the aryl boronic acids, good
  • yields of the resultant styryl adducts 27–30 were observed. It was found that employment of the boronic acids in excess (approximately 5 equiv) in conjunction with base work-up gave the desired products in good yields with no starting material 24a, or the product of bromine–hydrogen exchange 5a
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Published 25 Nov 2009

Polyionic polymers – heterogeneous media for metal nanoparticles as catalyst in Suzuki–Miyaura and Heck–Mizoroki reactions under flow conditions

  • Klaas Mennecke and
  • Andreas Kirschning

Beilstein J. Org. Chem. 2009, 5, No. 21, doi:10.3762/bjoc.5.21

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  • following. Under these optimized conditions several examples of successful cross coupling reactions were achieved that are listed in Table 1. We included combinations of electron rich and electron deficient aryl bromides with functionalized boronic acids and yields of coupling products were commonly good to
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Published 08 May 2009

Convenient methods for preparing π-conjugated linkers as building blocks for modular chemistry

  • Jiří Kulhánek,
  • Filip Bureš and
  • Miroslav Ludwig

Beilstein J. Org. Chem. 2009, 5, No. 11, doi:10.3762/bjoc.5.11

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  • ′-bromobiphenyl intermediates necessary for the preparation of 4a–c were synthesized by the Suzuki–Miyaura cross-coupling of 1-bromo-4-iodobenzene with the corresponding boronic acids/esters 1a–c in the yields of 82, 84, and 91%, respectively. A routine procedure involving a lithiation and reaction with
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Published 14 Apr 2009

Catalytic synthesis of (E)-α,β-unsaturated esters from aldehydes and 1,1-diethoxyethylene

  • Rubén Manzano,
  • Lidia Ozores,
  • Andreas Job,
  • Lars Rodefeld and
  • Benjamin List

Beilstein J. Org. Chem. 2009, 5, No. 3, doi:10.3762/bjoc.5.3

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  • transformation. After screening various catalysts and different reaction conditions, we found that boronic acids [34], especially 2,4,5-trifluorophenylboronic acid, proved to be quite active catalysts of the condensation of benzaldehyde with ketene diethyl acetal (Table 1). Brønsted acids are also effective but
  • mechanism that explains the peculiar effectiveness of boronic acids as catalysts (Scheme 2). Accordingly, the boronic acid functions as a Lewis acid activating the aldehyde but also as a hydroxide donor facilitating the departure of ethanol from an activated intermediate. Clearly, alternative mechanisms may
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Preliminary Communication
Published 30 Jan 2009

Mechanistic aspects of the isomerization of Z-vinylic tellurides double bonds in the synthesis of potassium Z-vinyltrifluoroborate salts

  • Hélio A. Stefani,
  • Rafael C. Guadagnin,
  • Artur F. Keppler,
  • Giancarlo V. Botteselle,
  • João V. Comasseto and
  • Carlos A. Suganuma

Beilstein J. Org. Chem. 2008, 4, No. 9, doi:10.1186/1860-5397-4-9

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  • experiments the radical species that promoted the stereoinversion of Z-vinylic organometallic species during the preparation of potassium vinyltrifluoroborate salts was identified. The experiments support the proposed mechanism, which is based on the homolytic cleavage of the TenBu bond. Background Boronic
  • acids and boronate esters are the most commonly used derivatives in Suzuki-Miyaura cross-coupling reactions. Recently, Molander et al. [1] and our group [2] have explored the use of potassium organotrifluoroborate salts as an alternative to the usual organoboron reagents in alkenyl-alkenyl [3], aryl
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Published 05 Feb 2008

A convenient catalyst system for microwave accelerated cross- coupling of a range of aryl boronic acids with aryl chlorides

  • Matthew L. Clarke,
  • Marcia B. France,
  • Jose A. Fuentes,
  • Edward J. Milton and
  • Geoffrey J. Roff

Beilstein J. Org. Chem. 2007, 3, No. 18, doi:10.1186/1860-5397-3-18

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  • microwave accelerated cross-coupling procedure between aryl chlorides with a range of boronic acids has been developed. An explanation for the low reactivity of highly fluorinated boronic acids in Suzuki coupling is provided. Background The Suzuki cross-coupling represents an extremely useful method for
  • a range of aryl boronic acids under microwave heating conditions. In this paper we report these results, including our observations on why heavily fluorinated boronic acids are such poor nucleophiles in this chemistry. Findings In our original studies under conventional conditions, it was found that
  • evaluate this aspect, so we elected to investigate the effect of the boronic acid component using one aryl chloride substrate, 4-chloro-acetophenone. Representative results are compiled in Table 1. A range of boronic acids can be coupled with high conversion and good to excellent isolated yield for the
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Preliminary Communication
Published 30 May 2007
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