Ausgehend von Phenyl- (1) und 2-Thienylbernsteinsäure (2) wurden über die 3-monosubstituierten Pyrrolidindione 3/4 die basech substituierten Pyrrolidindione 5/6 synthetisiert。Durch katalytische Hydrierung der 3-Phenylverbindungen 5 wurden die 3-Cyclohexylpyrrolidindione 7 hergestellt。Die Enantiomere von 5a, 5b, 6a und 6b wurden durch Racematspaltung mit Binaphthylphosphorsäure, die von 5c und 5d durch
Synthesis of 3-Methylthio-4-aryl-3-pyrroline-2,5-diones and 3-Arylpyrrolidine-2,5-diones by Reaction of Nitroketene Dithioacetal with Arylacetonitriles
摘要:
The reaction of nitroketene dithioacetal (1a), i.e., 2,2-bis(methylthio)-1-nitroethylene, with arylacetonitriles (2a-I) in the presence of the base like sodium hydroxide gave 4-nitrobut-2-enenitriles (3a-I) which were converted into 5-hydroxyimino-4-methylthio-3-phenyl-3-pyrrolin-2-ones (4a-i) under refluxing in methanol. Title compounds (5a-i) were readily obtained by the treatment of 4a-i with hydrochloric acid and were finally led to N-methylated products (6a-I) with methyl iodide. The reduction of maleimides (4-6) with zinc dust in acetic acid afforded the corresponding 3-arylpyrrolidine-2,5-diones (7a-i) that can be converted to pharmacologycally active compounds like mesembrines.