Metallocene‐Catalyzed C7‐Linkage in the Hydrooligomerization of Norbornene by σ‐Bond Metathesis: Insight into the Microstructure of Polynorbornene

An unusual linkage: The zirconocene‐catalyzed hydrooligomerization of norbornene proceeds by σ‐bond metathesis to form a 2‐exo,7′‐syn linkage (as evident in the pentamer shown). The oligomers were characterized by gas chromatography, NMR spectroscopy , X‐ray crystallography, and DFT calculations

Configurationally Stable Chiral Dithia-Bridged Hetero[4]helicene Radical Cation: Electronic Structure and Absolute Configuration

A stable chiral hetero[4]helicene radical cation was synthesized and characterized by UV-Vis absorption and EPR spectroscopy as well as X-ray crystallography. For the first time a combination of chiroptical methods involving ECD, ORD, and VCD, supported by quantum mechanical predictions, enabled the elucidation of the absolute configuration of such open-shell helical species