A Triphenylene-Based Triptycene with Large Free Volume Synthesized by Zirconium-Mediated Biphenylation

Biphenylation using (Li(THF)<sub>4</sub>)<sub>2</sub>·Zr(biphe)<sub>3</sub> of hexabromotriptycenes bearing H (<b>1-H</b>) or Bu (<b>1-Bu</b>) at the bridgeheads gave triptycenes with triphenylene blades. The blades extend both perpendicular and parallel to the 3-fold axis and generate a large intramolecular free volume (IMFV) (<b>1-H</b>, AM1, 710 Å<sup>3</sup>; cf. triptycene, AM1 71 Å<sup>3</sup>). Crystals of <b>1-H</b> could not be obtained. Triptycene <b>1-Bu</b>, in which the Bu groups fill the voids near the bridgehead, was crystalline. X-ray diffraction analysis revealed crystal packing with alternating, interlocked corrugated and distorted hexagonal layers.