1.
Org Biomol Chem
; 1(12): 2168-72, 2003 Jun 21.
Article
in English
| MEDLINE
| ID: mdl-12945910
ABSTRACT
The aryl isocyanides 1-4 are converted at 150 degrees C into the hexameric pyrazino[1,2-a:4,5-a']diindoles 15-19. 4-Fluorophenyl isocyanide, when heated at 135 degrees C, gave the hexamer 19 and the tetrameric indigo di-arylimine 9, and when kept at ambient temperature gave mainly the tetramer 9 in low yield. The structures of the hexamer 19 and the tetramer 9 were established by X-ray crystallography. Mechanisms are proposed for the oligomerisation reactions.