Organylthio(silyl)carbenes

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Autor/in:
Erscheinungsjahr:
2009
Medientyp:
Text
Schlagworte:
  • Carbanions
  • Carbenes
  • Cycloadditioti
  • Diazo compounds
  • Sulfur heterocycles
Beschreibung:
  • The title carbenes 5 can be generated either from diazo compounds 9 by copper-catalyze d catalysis or from chloro(organylthio)methylsilanes 12 by base-induced α-elimination, This is confirmed, by [2+1] cycloadditions with alkenes to give the cyclopropanes 4a-d and. 14. Product 4a is identical with the product obtained from carbanion 1c, phenyloxirane, and styrene, for which a carbene intermediate 5a had been invoked. On heating in the presence of copper inflate, cyclopropane 4a undergoes ring enlargement to the thiochroman 11. With (Z)- or (E)-alkenes 20, carbene 5a gives stereospe-cific cyclopropane formation, although maleate turns out not to be a suitable indicator for a stereospecific cycloaddition. The suggested, singlet character of 5 is confirmed by DFT calculations (B3LYP/cc-pVTZ). The structures of cyclopropanes 4a and 23, as well as those of thiochroman 11 and carbene dimer 15, were confirmed by single-crystal X-ray investigations. © 2009 Wiley-VCH Verlag GmbH & Co. KGaA.
Lizenz:
  • info:eu-repo/semantics/closedAccess
Quellsystem:
Forschungsinformationssystem der UHH
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oai:www.edit.fis.uni-hamburg.de:publications/f166351f-86cb-4023-b5a6-98e3299e65f2