Monatshefte für Chemie / Chemical Monthly

, Volume 113, Issue 8–9, pp 1037–1044 | Cite as

Untersuchungen von Reaktionsmechanismen durch Isotopenmarkierung, VII. Zum Mechanismus der Ringverengung von 2,2-Dichlor-6-methyl-4H-1-thiochroman-3,4-dion

  • Peter Seidler
  • Gert Kollenz
Organische Chemie Und Biochemie

Mechanistic investigations by isotopic labeling, VII. Mechanism of the ring contraction reaction of 2,2-dichloro-6-methyl-4H-1-thiochroman-3,4-dione


It is shown by use of14C-labeling that the ring contraction reaction of 2,2-dichloro-6-methyl-4H-1-thiochroman-3,4-dione (1) leads to elimination of C-2 as CO2. Formation of the 5-methyl-2,3-dihydrobenzo[b]thiophen-2,3-dione (2) is suggested to proceed via hydrolytic opening of the thiolactone-binding in1. recyclisation and subsequent oxidation by unreacted1.


14C-Labeling 5-Methyl-2,3-dihydro-benzo[b]thiophen-2,3- dione Ring contraction reaction 


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Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Peter Seidler
    • 1
  • Gert Kollenz
    • 1
  1. 1.Institut für Organische ChemieUniversität GrazGrazÖsterreich

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