A Highly Configurationally Stable 4Heterohelicenium Cation

A 4 (hetero) helicenium cation was resolved using the hexacoordinated phosphorus-containing binphat anion (see picture: N, blue; O, red; C, gray). Its absolute configuration was determined by vibrational circular dichroism spectroscopy. The barrier of interconversion of its enantiomers is higher than that of 6helicene. Supporting information for this article is available on the WWW under http: //www. wiley-vch. de/contents/jc₂002/2003/z51443ₛ. pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.