Complexation of Fullerenes with Bis-calix[n]arenes Synthesized by Tandem Claisen Rearrangement1

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 of the other available p -positions has been found to be particularly effective.