2,7,12,17,22-Penta-tert-butyl-4,9,14,19,24-pentacyano-pentabenzo[ab,fg,kl,pq,uv]-[25]annulene (Compound CS, cyanostar)

This 5-fold symmetric cyclic molecule, called a macrocycle, has a positively charged central cavity that “captures” anions such as borates, chlorates, perchlorates, and phosphates. Pairs of cyanostars sandwich together, trapping the anion using their slightly concave shapes (not shown).

Designed at Indiana University Bloomington, the cyanostars have been shown to be able to be assembled into molecular structures called rotaxanes which resemble wheels and axles and act as simple molecular machines which can be manipulated by heat or light.

Piece requested by Jane.