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Search for "1,3-dipolar electrocyclization" in Full Text gives 5 result(s) in Beilstein Journal of Organic Chemistry.

Ambident reactivity of enolizable 5-mercapto-1H-tetrazoles in trapping reactions with in situ-generated thiocarbonyl S-methanides derived from sterically crowded cycloaliphatic thioketones

  • Grzegorz Mlostoń,
  • Małgorzata Celeda,
  • Marcin Palusiak,
  • Heinz Heimgartner,
  • Marta Denel-Bobrowska and
  • Agnieszka B. Olejniczak

Beilstein J. Org. Chem. 2025, 21, 1508–1519, doi:10.3762/bjoc.21.113

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  • regioselectivity in high yields. Upon heating to 65 °C in toluene solution, in analogy to the well-known compounds 2a and 2b, they extruded N2 and the in situ-generated reactive thiocarbonyl S-methanides 1c and 1d, in absence of any trapping reagent, underwent 1,3-dipolar electrocyclization yielding the
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Published 23 Jul 2025

Dimerization reactions of aryl selenophen-2-yl-substituted thiocarbonyl S-methanides as diradical processes: a computational study

  • Michael L. McKee,
  • Grzegorz Mlostoń,
  • Katarzyna Urbaniak and
  • Heinz Heimgartner

Beilstein J. Org. Chem. 2017, 13, 410–416, doi:10.3762/bjoc.13.44

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  • pathway via a diradical intermediate leading to the formation of the unusual macrocyclic dimer 9 by computational methods. First calculations were made for phenyl selenophen-2-yl thiocarbonyl S-methanide (8A), which can undergo a 1,3-dipolar electrocyclization (1,3-ring closure) to form the thiirane 3a
  • course of the dimerization of a reactive diaryl thiocarbonyl S-methanides. Potential 1,3-dipolar electrocyclization of thiocabonyl S-methanide 8A. Computed enthalpies (free energies in parentheses) at 298 K at the SMD(tetrahydrofuran)/M06-2X/6-311+G(2df,p)//M06-2X/6-31G(d) level of theory. Stepwise
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Published 03 Mar 2017

Diradical reaction mechanisms in [3 + 2]-cycloadditions of hetaryl thioketones with alkyl- or trimethylsilyl-substituted diazomethanes

  • Grzegorz Mlostoń,
  • Paulina Pipiak and
  • Heinz Heimgartner

Beilstein J. Org. Chem. 2016, 12, 716–724, doi:10.3762/bjoc.12.71

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  • . Only after warming up above −45/40 °C compounds 2 are expected to decompose yielding the reactive thiocarbonyl ylide 3. Under these conditions, the latter intermediates can undergo either 1,3-dipolar electrocyclization to give thiiranes 8 or dimerization leading to 1,4-dithianes 4 [20][26]. This
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Published 14 Apr 2016

On the strong difference in reactivity of acyclic and cyclic diazodiketones with thioketones: experimental results and quantum-chemical interpretation

  • Andrey S. Mereshchenko,
  • Alexey V. Ivanov,
  • Viktor I. Baranovskii,
  • Grzegorz Mloston,
  • Ludmila L. Rodina and
  • Valerij A. Nikolaev

Beilstein J. Org. Chem. 2015, 11, 504–513, doi:10.3762/bjoc.11.57

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  • diazodiketones 1e,f. Transformations of thiocarbonyl ylides 7 and 7' In order to evaluate the correlation between the structure of thiocarbonyl ylides 7, 7' and the direction of their electrocyclizations (1,5- or 1,3-dipolar electrocyclization), the relative energies of the stationary points on the potential
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Published 20 Apr 2015

Less reactive dipoles of diazodicarbonyl compounds in reaction with cycloaliphatic thioketones – First evidence for the 1,3-oxathiole–thiocarbonyl ylide interconversion

  • Valerij A. Nikolaev,
  • Alexey V. Ivanov,
  • Ludmila L. Rodina and
  • Grzegorz Mlostoń

Beilstein J. Org. Chem. 2013, 9, 2751–2761, doi:10.3762/bjoc.9.309

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  • -oxathiole to alkene were performed at the DFT PBE1PBE/6-31G(d) level. Keywords: 1,3-dipolar electrocyclization; 1,5-dipolar electrocyclization; 1,3-oxathioles; thiocarbonyl ylides; thiiranes; thioketones; Introduction Aryl- and alkylsubstituted thioketones exhibit high 1,3-dipolar reactivity towards
  • intermediate 1,3,4-thiadiazoline or a diazonium zwitterion. Next, electrocyclization of the transient thiocarbonyl ylide leads to spirocyclic 1,3-oxathioles in yields of up to 88%. In similar reactions of diazomalonate 2e, a competitive process of 1,3-dipolar electrocyclization is observed. It led to the
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Published 02 Dec 2013
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