Nonplanar Aromatic Compounds. 9. Synthesis, Structure, and Aromaticity of 1:2,13:14-Dibenzo[2]paracyclo[2](2,7)- pyrenophane-1,13-diene

Abstract

Pyrenophane (6) and an octaphenyl derivative (16) were synthesized using two different routes. Both cyclophanes contain a severely bent pyrene unit (6: theta = 93.6 degrees and 16: theta = 95.8 degrees , according to DFT-calculations (B3LYP/6-311G**)), which was generated at room temperature by a valence isomerization/dehydrogenation (VID) reaction. HOMA and NICS indicate 92-98% retention of aromaticity of the highly distorted pyrene systems compared to planar pyrene.