Novel Bicyclic P,S-Heterocycles via Stereoselective hetero-Diels–Alder Reactions of Thiochalcones with 1-Phenyl-4H-phosphinin-4-one 1-Oxide

Grzegorz Mlostoń; Katarzyna Urbaniak; Marcin Palusiak; Elżbieta Łastawiecka; Sławomir Frynas; Kazimierz Michał Pietrusiewicz; Heinz Heimgartner

doi:10.3390/molecules29092036

Molecules (Apr 2024)

Novel Bicyclic P,S-Heterocycles via Stereoselective hetero-Diels–Alder Reactions of Thiochalcones with 1-Phenyl-4H-phosphinin-4-one 1-Oxide

Grzegorz Mlostoń,
Katarzyna Urbaniak,
Marcin Palusiak,
Elżbieta Łastawiecka,
Sławomir Frynas,
Kazimierz Michał Pietrusiewicz,
Heinz Heimgartner

Affiliations

Grzegorz Mlostoń: Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91-403 Lodz, Poland
Katarzyna Urbaniak: Department of Organic and Applied Chemistry, Faculty of Chemistry, University of Lodz, Tamka 12, 91-403 Lodz, Poland
Marcin Palusiak: Department of Physical Chemistry, Faculty of Chemistry, University of Lodz, Pomorska 163/165, 90-236 Lodz, Poland
Elżbieta Łastawiecka: Department of Organic and Crystal Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University, Gliniana 33, 20-614 Lublin, Poland
Sławomir Frynas: Department of Organic and Crystal Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University, Gliniana 33, 20-614 Lublin, Poland
Kazimierz Michał Pietrusiewicz: Department of Organic and Crystal Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Skłodowska University, Gliniana 33, 20-614 Lublin, Poland
Heinz Heimgartner: Department of Chemistry, University of Zurich, Winterthurerstrasse 190, CH-8057 Zurich, Switzerland

DOI: https://doi.org/10.3390/molecules29092036
Journal volume & issue: Vol. 29, no. 9
p. 2036

Abstract

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Thiochalcones undergo cycloaddition reactions in THF solution at 60 °C with the synthetically unexplored 1-phenyl-4H-phosphinin-4-one 1-oxide in a highly regio- and stereoselective manner, yielding hitherto unknown bicyclic P,S-heterocycles containing fused thiopyran and phosphinine rings. The stereochemical structures of two of the obtained (4+2)-cycloadducts were unambiguously assigned by means of the X-ray single-crystal analysis. Based on these assignments, a concerted mechanism of the hetero-Diels–Alder reaction via the preferred endo approach of the heterodiene from the less hindered P=O side of the phosphininone molecule is postulated to explain the established rac-(4RS,8SR,9SR,10SR)-configured (4+2)-cycloadducts isolated as major products.

Published in Molecules

ISSN: 1420-3049 (Online)
Publisher: MDPI AG
Country of publisher: Switzerland
LCC subjects: Science: Chemistry: Organic chemistry
Website: http://www.mdpi.com/journal/molecules

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