Fulleropillar[4]arene: The Synthesis and Complexation Properties

A multihydroquinone ether dialdehyde derivative <b>2</b> was incidentally obtained through an unexpected ring opening of pillar[4]­arene[1]­quinone <b>1</b>. And the Prato reaction of <b>2</b> with [60]­fullerene led to [60]­fullerene bisadducts, from which <i>trans-4</i> cyclic regioisomer <b>3</b> was isolated and characterized. The fulleropillar[4]­arene <b>3</b> showed a larger cavity and can accommodate a viologen derivative <b>C</b>_<b>12</b><b>V</b>^<b>2+</b> with a much stronger affinity than permethyl pillar[5]­arene (<b>MP5</b>) and pillar[4]­arene[1]­quinone <b>1</b>.