Overcoming Molecular Strain: Synthesis of [7]Cycloparaphenylene

The cycloparaphenylenes (CPPs) are fully aromatic nanohoops consisting solely of para-linked benzene rings. While these unique structures were first envisioned over 70 years ago, they have only recently been prepared in the laboratory. This work highlights important historical approaches towards the CPP class of molecules, the recent flurry of successful syntheses of a variety of CPPs, and our synthesis of the most strained cycloparaphenylene thus far, [7]CPP.