Conversion from pillar[5]arene to pillar[6-15]arenes by ring expansion and encapsulation of C60 by pillar[n]arenes with nanosize cavities.

Conversion of ring size from pillar[5]arene to pillar[6-15]arenes and isolation of pillar[n]arene homologues (n = 11-13) with known pillar[n]arene homologues (n = 6-10) are demonstrated. Pillar[10]arene formed the most stable host-guest complex with C60 among the pillar[5-14]arenes.