Complexation of fullerenes with bis-calix[n]arenes synthesized by tandem Claisen rearrangement

Bis-calix[n]arenes that are singly and doubly bridged at the upper rims with 2-butenyl or 2-methylenepropyl moieties have been prepared by tandem Claisen rearrangement of bis-calix[n]arenes that are singly and doubly bridged via ether linkages at the lower rims with these same spanners. The complexation behavior of these bis-calixarenes toward C-60 and C-70 has been measured, and a calix[5]arene singly bridged at the upper rims with a 2-butenyl spanner and carrying allyl groups at all bf the other available p-positions has been found to be particularly effective.