Abstract
This account mainly describes the synthesis and functions of novel artificial double helices recently developed by our group. We have proposed the first design rationale for artificial double helices with a controlled helicity by employing chiral amidinium-carboxylate salt bridges with m-terphenyl ligands, and synthesized several artificial double helices together with triple- and quadruple-stranded helices. An artificial double helix bearing Pt (II) -acetylide complex moieties has proven effective as a catalyst for the asymmetric cyclopropanation, demonstrating that the chiral space provided by double helices can be effective for asymmetric catalytic reactions. Furthermore, we have serendipitously discovered a spiroborate-based double helicate bearing oligophenol strands and water-soluble double helices of oligoresorcinols. The oligoresorcinol double helices bound cyclic and linear oligosaccharides in water to form rotaxanes and hetero-double helices, respectively, with a remarkable selectivity for the glucosidic linkage patterns and chain lengths.
