A Straightforward Route to Helically Chiral N‐Heteroaromatic Compounds: Practical Synthesis of Racemic 1,14‐Diaza[5]helicene and Optically Pure 1‐ and 2‐Aza[6]helicenes

Abstract

The taming of the screw: The CoI-catalyzed cyclotrimerization of triynes and microwave (MW) assisted aromatization with MnO2 are central to the practical synthesis of diaza[5]helicene and aza[6]helicenes. The aza[6]helicene racemates have been resolved, the absolute configuration of the enantiomers assigned, the energy barriers to racemization determined, and X-ray structures of their Ag complexes obtained (see picture; Cp=C5H5, OTf=triflate). Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z705463_s.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.