Enyne[3]cumulene. Synthesis and mode of aromatization
摘要:
The noncyclic cross-conjugated diene-diyne system 4 undergoes the thiol-triggered vinylogous propargylic rearrangement (vinylogous S(N)2' reaction) in the presence of amine leading to isolable enyne[3]cumulene 5, which is capable of not only Bergman-type cyclization but also [2 + 2] cycloaddition reaction to produce benzocyclobutane derivative 14 when heated.