This review describes the properties of the bambus[n]urils and some of their applications. These macrocycles are synthesized by the condensation of glycoluril derivatives and paraformaldehyde in acid medium. The alternate conformation of the monomers creates low electron density regions at the center of the macrocycle cavity and this is the main cause of bambus[n]urils high affinity and selectivity towards anions. Due to these properties, bambus[n]urils have been used for the detection of anions in mixtures, but also in complex supramolecular systems where they act as donors in photoinduced electron-transfer processes, and synthetic ion-channels for example. These compounds are relatively recent and deserve attention for their potential in many branches of chemistry, especially in supramolecular and inclusion chemistry.

The reaction of Naphthalene 1,4,5,8-dianhydride (NTCDA) with elemental aluminum(0) powder is studied in an aqueous alcoholic KOH mixture to search for the NTCDA anion and dianion electron-adducts. After analyzing various reaction conditions it was found that the reaction yielded a greenish precipitate in 3:1 (v:v) ethanol:water mixture. This powder is composed mainly of aluminum trihydroxide crystallites of bayerite [α-Al(OH3)(s)] and the organic content is approximately 6%. This hybrid material proved to be paramagnetic even after exposure to air for one year and at temperatures up to 200 ºC. Typical carbonylic bound to metal IR bands and reflectance UV-VIS spectra demonstrate the entrapment of NTCDA radical anion into the aluminum trihydroxide, hence rendering its green color and a paramagnetic behavior. Thus, besides the understanding of an aluminum reaction in suspension, the entrapment of an organic material (NTCDA) that stays stable as the corresponding radical can provide an interesting option for the synthesis of aluminum trihydroxide composites.

This review article describes the properties and the main applications of the glicol[n]urils. These compounds are cavitands made of n glycolurilic units arranged in circles, giving rise to extremely symmetric toroidal molecules. The cucurbit[n]urils create this way variable-sized hydrophobic cavities and the glycolurilic carbonyles delimit two portals on these cavities, slightly narrower than their internal radii. Their structure, physical and chemical properties favor the formation of inclusion compounds, and turn them into important building blocks for supramolecular chemistry and nanotechnology.