Theoretical energy-based conformational analysis of divinyl selenide performed at the MP2/6-311G** level is substantiated by the second-order polarization propagator approach (SOPPA) calculations and experimental measurements of its (77)Se-(1)H spin-spin coupling constants, demonstrating marked stereochemical behavior in respect of the internal rotation of both vinyl groups around the Se-C bonds. Based on these data, divinyl selenide is shown to exist in an equilibrium mixture of three nonplanar conformers: one the preferred syn-s-cis-s-trans and two minor anti-s-trans-s-trans and syn-s-trans-s-trans forms.
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http://dx.doi.org/10.1002/mrc.2291 | DOI Listing |
Molecules
February 2021
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of The Russian Academy of Sciences, 1 Favorsky Str., 664033 Irkutsk, Russia.
Regioselective synthesis of novel 2,3-[1,4]thiazino[2,3,4-]quinolin-4-ium derivatives has been developed by annulation reactions of 8-quinolinesulfenyl halides with vinyl chalcogenides (vinyl ethers, divinyl sulfide, divinyl selenide and phenyl vinyl sulfide) and tetravinyl silane. The novel reagent 8-quinolinesulfenyl bromide was used in the annulation reactions. The influence of the substrate structure and the nature of heteroatoms on the direction of the reactions and on product yields has been studied.
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December 2020
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Division of The Russian Academy of Sciences, 1 Favorsky Str., 664033 Irkutsk, Russia.
The efficient regio- and stereoselective synthesis of (,)-3,3'-selanediylbis(2-propenamides) in 76-93% yields was developed based on the reaction of sodium selenide with 3-trimethylsilyl-2-propynamides. (,)-3,3'-Selanediylbis(2-propenamides) are a novel class of organoselenium compounds. To date, not a single representative of 3,3'-selanediylbis(2-propenamides) has been described in the literature.
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February 2017
Department of Pharmaceutical Sciences, Group of Catalysis and Organic Green Chemistry, University of Perugia, Via del Liceo 1, 06100 Perugia, Italy.
A simple and efficient protocol to prepare divinyl selenides has been developed by the regio- and stereoselective addition of sodium selenide species to aryl alkynes. The nucleophilic species was generates in situ from the reaction of elemental selenium with NaBH₄, utilizing PEG-400 as the solvent. Several divinyl selenides were obtained in moderate to excellent yields with selectivity for the (,)-isomer by a one-step procedure that was carried out at 60 °C in short reaction times.
View Article and Find Full Text PDFMagn Reson Chem
October 2008
A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, Favorsky St. 1, 664033 Irkutsk, Russia.
Theoretical energy-based conformational analysis of divinyl selenide performed at the MP2/6-311G** level is substantiated by the second-order polarization propagator approach (SOPPA) calculations and experimental measurements of its (77)Se-(1)H spin-spin coupling constants, demonstrating marked stereochemical behavior in respect of the internal rotation of both vinyl groups around the Se-C bonds. Based on these data, divinyl selenide is shown to exist in an equilibrium mixture of three nonplanar conformers: one the preferred syn-s-cis-s-trans and two minor anti-s-trans-s-trans and syn-s-trans-s-trans forms.
View Article and Find Full Text PDFJ Org Chem
January 2003
Departamento de Química, Universidade Federal de Santa Maria, C. P. 5001, CEP 97105-900, RS, Brazil.
(Z,Z)- and (E,E)-divinylic selenides and telurides undergo direct coupling with terminal alkynes in the presence of a nickel/CuI catalyst at room temperature to give (Z)- and (E)-enyne systems in good yields and with complete retention of configuration.
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