Synthesis, structures, and optical properties of aza[4]helicenes

Abstract

A series of aza[4]helicenes have been conveniently synthesized in yields of 71-92 % by a one-pot procedure involving the Pictet-Spengler reaction. The structures of the aza[4]helicenes were characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and X-ray crystallography. Moreover, it was found that the aza[4]helicenes self-assemble into 2D layers or herringbone-like structures in the solid state. In addition, the optical properties were investigated by UV and fluorescence spectroscopic methods. A series of aza[4]helicenes have been conveniently synthesized by the Pictet-Spengler reaction and characterized by 1H and 13C NMR spectroscopy, mass spectrometry, and X-ray crystallography. Their self-assembling behavior in the solid state as well as their optical properties have also been investigated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.