DITHIOCARBOXYLIERUNGSREAKTIONEN VON cis-BICYCLO[3.3.0]OCTAN-3,7-DIONEN. MOLEKÜL- UND KRISTALLSTRUKTUR VON cis-2,6-BIS(DIMETHYLTHIO-METHYLEN)-BICYCLO[3.3.0]OCTAN-3,7-DION

Abstract

The cis-bicyclo[3.3.0]octane-3,7-dione 1a and its 1,5-dimethyl derivative 1b react with carbon disulfide, strong base and an alkylating agent in dipolar aprotic solvents giving racemic mixtures of 2-dialkylthio-methylene compounds 2, whereas in the presence of two equivalents of carbon disulfide and the appropriate amount of base and further alkylating agent the cis-2,6-bis(dimethylthio-methylene) derivatives 3 are formed. The crystal and molecular structure of 3a has been investigated by X-ray analysis.

Key Words:

• cis-Bicyclo[3.3.0]octane-3,7-dione
• cis-1,5-dimethylbicyclo[3.3.0]octane-3
• 7-dione
• carbon disulfide
• cis-2-(dialkylthio-methylene)-bicyclo[3.3.0]octane-3,7-dione
• cis-2
• 6-bis(dimethylthio-methylene)-bicyclo[3.3.0]octane-3
• 7-dione
• crystal structure