Self-assembling supramolecular daisy chains

Self-complementary monomers, incorporating a macrocyclic polyether 'head' with an acyclic bipyridinium-based 'tail', self-assemble spontaneously in solution to afford an equilibrium mixture of dimeric, trimeric, tetrameric, and pentameric supermolecules (see schematic diagram on the right) having masses of up to at least 5000 u. A cyclic dimer, which crystallized from the mixture of acyclic and cyclic supermolecules, has been characterized by X-ray chromatography.