Cyclic bicalicene

This novel calicene chemistry has been further developed into the synthesis of novel heterocycles (e.g., 31) and cyclic compounds built up of only calicene moieties, i.e. cyclic bicalicene (pen-tacyclo[11.3.0.0. 0- .0 ]hexadeca-l,3,5,7,9,ll,13,15-octaene, 5), tercalicene (6), and quatercalicene (7) as stable compounds. ... 

Figure 6.7 Triafulvenes 2, calicene 8, benzotriafulvenes 28 and cyclic bicalicene 29.

In 1984, Yoshida and coworkers synthesized cyclic bicalicenes 29 as outlined in Scheme 6.7 [21, 28]. Although parent calicene 8 is a highly reactive species, 29 is a... 

---