Efficient syntheses of pillar[6]arene-based hetero[4]rotaxanes using a cooperative capture strategy

Abstract

While a single pillar[6]arene ring, nestling between two cucurbit[6]uril rings in a series of three hetero[4]rotaxanes, is conformationally mobile in solution, it adopts the energetically most favourable conformation with local C3V symmetry in the solid state.