Calix[2]naphth[2]arene: A Class of Naphthalene-Phenol Hybrid Macrocyclic Hosts

Calix[2]naphth[2]arenes make up a new class of phenol-naphthalene hybrid macrocycles. X-ray studies show that calix[2]naphth[2]arene 1 adopts a 1,2-alternate conformation. Alkali metal cations are complexed by the calixnaphtharenes in a 1,2-alternate conformation, by cation···πinteractions with the naphthalene walls, and by RO···M+ ion-dipole interactions. In the presence of Cs+, chiral complexes of calixnaphtharenes 5 and 6 were observed in which the cation is nested on one of the two faces of the macrocycle.