C₃‐Symmetric Hexakis(trimethylsilyl)[7]phenylene[“Tris(biphenylenocyclobutadieno)cyclohexatriene”], a Polycyclic Benzenoid Hydrocarbon with Slightly Curved Topology

In four steps and a yield of 14%, the [7]phenylene 1 has been prepared from hexakis(trimethylsilylethynyl)-benzene. The trigonal 1 is not planar but slightly curved, and the unit cell features two molecules, staggered and offset, facing each other in a concave–concave arrangement.