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Search for "azoalkenes" in Full Text gives 4 result(s) in Beilstein Journal of Organic Chemistry.

Recent advances in organocatalytic atroposelective reactions

  • Henrich Szabados and
  • Radovan Šebesta

Beilstein J. Org. Chem. 2025, 21, 55–121, doi:10.3762/bjoc.21.6

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  • ketoesters 207 and azoalkenes 208 catalyzed by CPA C47 forming the axially chiral products 209 (Scheme 62) [92]. The majority of the products were obtained in very good yields and nearly all possessed excellent enantiomeric purities. Racemization experiments were carried out in m-xylene and toluene. The
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Published 09 Jan 2025

Non-covalent organocatalyzed enantioselective cyclization reactions of α,β-unsaturated imines

  • Sergio Torres-Oya and
  • Mercedes Zurro

Beilstein J. Org. Chem. 2024, 20, 3221–3255, doi:10.3762/bjoc.20.268

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  • indoles 52 via a (3 + 2) cyclization with azoalkenes 53 catalyzed by chiral phosphoric acid XIV (Scheme 20). This methodology enables the synthesis of a wide scope of pyrroloindolines 54, important privileged polycyclic indolines in high yields (72–99%) and high enantioselectivities (90–99%) [43]. The
  • + 3) cycloaddition of 3-alkyl-2-vinylindoles 59 and azoalkenes 53 (Scheme 22). This methodology afforded chiral pyrroloindolines 60 bearing two tetrasubstituted stereogenic centers in good yields (61–96%) and excellent stereoselectivities (all >95:5 dr, 86–99% ee) by using chiral phosphoric acid XVII
  • reaction between 1,3-dicarbonyl compounds 68 and azoalkenes 53 (Scheme 26) [48]. This methodology provides access to C1-symmetric biarylamino alcohol derivatives (NPNOL) 69 in a wide scope with good yields (45–89%) and good to excellent atroposelectivities (64–99% ee). In order to explain the reaction
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Published 10 Dec 2024

Construction of diazepine-containing spiroindolines via annulation reaction of α-halogenated N-acylhydrazones and isatin-derived MBH carbonates

  • Xing Liu,
  • Wenjing Shi,
  • Jing Sun and
  • Chao-Guo Yan

Beilstein J. Org. Chem. 2023, 19, 1923–1932, doi:10.3762/bjoc.19.143

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  • alternative synthetic methodologies for functionalized 1,2-diazepines has drawn extensive attention [14][15][16][17][18][19][20][21]. One of the most attractive strategies to synthesize the 1,2-diazepine motif represents the [4 + 3] cycloaddition reaction between activated azoalkenes and 1,3-dipolarophiles
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Published 18 Dec 2023

Construction of bis-, tris- and tetrahydrazones by addition of azoalkenes to amines and ammonia

  • Artem N. Semakin,
  • Aleksandr O. Kokuev,
  • Yulia V. Nelyubina,
  • Alexey Yu. Sukhorukov,
  • Petr A. Zhmurov,
  • Sema L. Ioffe and
  • Vladimir A. Tartakovsky

Beilstein J. Org. Chem. 2016, 12, 2471–2477, doi:10.3762/bjoc.12.241

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  • alkylations of amines and ammonia with azoalkenes (generated from α-halohydrazones) were demonstrated as an efficient approach to poly(hydrazonomethyl)amines – a novel class of polynitrogen ligands. An intramolecular cyclotrimerization of C=N bonds in tris(hydrazonomethyl)amine to the respective 1,4,6,10
  • -tetraazaadamantane derivative was demonstrated. Keywords: azoalkenes; α-halogen hydrazones; heterocage compounds; hydrazone ligands; Michael addition; Introduction Hydrazones are extensively used as key structural units in the design of various functional molecular and supramolecular architectures [1][2][3][4][5
  • straightforward methodology based on multiple Michael-type additions of azoalkenes A (generated from α-halogen azacarbonyl precursor 1 [35][36][37][38][39]) to amines or ammonia (Scheme 1). Though the chemistry and synthetic potential azoalkenes A have been a subject of considerable interest in the recent years
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Published 21 Nov 2016
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