Hexaphenylbenzenes as Potential Acetylene Sponges

Acetylene sponges can be created by taking advantage of the nonplanar geometry of hexaphenylbenzenes and the special capacity of the central aromatic ring to engage in C(sp)-H center dot center dot center dot pi interactions reinforced by secondary C(sp(2))-H center dot center dot center dot pi interactions, as revealed by X-ray crystallographic studies and DFT calculations.