6176-91-6Relevant academic research and scientific papers
A New Method for the Synthesis of Imidazolidinone- and Benzimidazolone-containing [2.2]Cyclophanes
Ellis, Keisha K.,Wilke, Burkhardt,Zhang, Yuegang,Diver, Steven T.
, p. 3785 - 3788 (2007/10/03)
formula presented A novel acid-catalyzed double nucleophilic addition of bisthiols to heterocyclic bisacetals gives sulfur-containing macrocycles in good yield. Crossover experiments revealed that the acid-catalyzed N-acyl iminium cyclization for the imidazolidinones is reversible. The sulfur atom in the bridge was extruded photochemically, giving new [2.2]heterophanes containing the imidazolidinone and benzimidazolone ring systems. The determined crystal structures for representative members in the benzimidazolone series are also reported.
Chiral dithia[n]paracyclophanes - Synthesis, crystal structure, and chiroptical properties
Pischel, Ivo,Nieger, Martin,Archut, Andreas,Voegtle, Fritz
, p. 10043 - 10052 (2007/10/03)
The synthesis of the shortly bridged dithia[n]paracyclophanes (n = 7, 8) 1-5 was achieved by the cesium-assisted high-dilution cyclization for the first time. A chiral molecular structure is induced by the pattern of the two methyl substituents. A structure with C1 symmetry for the dithia[7]paracyclophane 1 is proven by X-ray structure analysis and by low-temperature NMR experiments. The benzene ring is strongly deformed to a boat-shaped conformation. Enantiomeric separation of the cyclophanes 2-5 and the circular dichrograms of the enantiomers are discussed.
