Crystal structure and rotational barrier of octakis(bromomethyl)naphthalene

Cyclic π-electron delocalization in non-planar linear acenes

Based on the experimental data of newly determined structures ofper-substituted naphthalenes by halogen atoms (F, Cl and Br) and perchloroanthracene, as well as on the molecular modeling we have shown that deviation from planarity leads to relatively small changes in the cyclic π-electron delocalization of acenes.

Novel Synthetic Route to Octasubstituted Naphthalenes from Four Alkynes and One Olefin Unit via Zirconacyclopentadienes and 1,2-Diiodo-3,4,5,6-tetraalkylbenzene

1,2,3,4-Tetrasubstituted benzene derivatives were prepared by the reaction of zirconacyclopentadienes with vinyl bromide in the presence of NiCl(2)(PPh(3))(2). 1,2-Diiodo-3,4,5,6-tetraalkylbenzenes were formed by treatment of 1,2,3,4-tetraalkylbenzenes with iodine and periodic acid in the presence of a catalytic amount of sulfuric acid. Reaction of the 1,2-diiodo-3,4,5,6-tetraalkylbenzenes with zirconacyclopentadienes in the presence of a stoichiometric amount of CuCl gave sterically crowded octasubstituted naphthalenes in moderate yields.