Benzoins and cyclobenzoins in supramolecular and polymer chemistry.

Benzoin condensation is one of the oldest rigorously described organic reactions, having been discovered in 1832 by Liebig and Wöhler. It creates a new C-C bond and a stereocenter from ubiquitous aldehyde starting materials under simple cyanide-catalyzed conditions. We have recently discovered cyclobenzoins: a class of macrocyclic compounds prepared by a benzoin cyclooligomerization of simple aromatic dialdehydes. Cyclobenzoins' internal cavities suggest they should be intriguing solution-phase supramolecular hosts, while their crystallographic packing aligns these cavities into potentially useful pores in the solid state. Well-precedented derivatization chemistry allows rapid functionalization into heteroacenes, which are optoelectronic materials and models for graphene defects. This Feature Article summarizes our work on cyclobenzoins, together with other applications of benzoins in supramolecular chemistry and materials science.