Abstract In the presence of triphenylphosphine, nickelocene reacts with tetrachloromethane to give (trichloromethyl) cyclopentadiene, which can be dehydrohalogenated to 6, 6- dichlorofulvene. It reacts analogously with tetrabromomethane and (trichloromethyl) benzene. 3-Bromopropene reacts with nickelocene to give allylcyclopentadiene.
