In order to find out substituent groups which provide stability and solubility to tetrakisdehydro [18] annulene system without appreciable electronic interaction with the annulene ring, the synthesis of 1, 5, 10, 14-tetra-tert-butyl-6, 8, 15, 17-tetrakisdehydro [18] annulene (VIII) has been catrried out starting from 3-tert-butyl-2-penten-4-ynal (III). It was found that the tetra-tert- butyl derivative (VIII) is strongly diatropic, and more stable and much more soluble than ...
