Furusho Yoshio, Yashima Eiji
Yashima Super-structured Helix Project, Exploratory Research for Advanced Technology (ERATO), Japan Science and Technology Agency (JST), Creation Core Nagoya 101, 2266-22 Shimoshidami, Moriyama-ku, Nagoya 463-0003, Japan.
Chem Rec. 2007;7(1):1-11. doi: 10.1002/tcr.20097.
This account describes novel artificial double helices recently developed by our group. We have designed and synthesized the double helices consisting of two complementary, m-terphenyl-based strands that are intertwined through chiral amidinium-carboxylate salt bridges. Due to the chiral substituents on the amidine groups, the double helices adopted an excess one-handed helical conformation in solution as well as in the solid state. By extending the modular strategy, we have synthesized double helices bearing Pt(II) linkers, which underwent the double helix-to-double helix transformations through the chemical reactions of the Pt(II) complex moieties. In addition, artificial double-stranded metallosupramolecular helical polymers were constructed by combining the salt bridges and metal coordination. In contrast to the design-oriented double helices based on salt bridges, we have serendipitously developed a spiroborate-based double helicate bearing oligophenol strands. The optical resolution of the helicate was successfully attained by a diastereomeric salt formation. We have also unexpectedly found that oligoresorcinols consisting of a very simple repeating unit self-assemble into double helices with the aid of aromatic interactions in water. Furthermore, a bias in the twist sense of the double helices can be achieved by incorporating chiral substituents at both ends of the strands.
本报告描述了我们团队最近开发的新型人工双螺旋结构。我们设计并合成了由两条互补的间三联苯基链组成的双螺旋结构，它们通过手性脒基羧酸盐桥相互缠绕。由于脒基上的手性取代基，双螺旋结构在溶液和固态中都呈现出过量的单手螺旋构象。通过扩展模块化策略，我们合成了带有Pt(II)连接体的双螺旋结构，它们通过Pt(II)配合物部分的化学反应发生双螺旋到双螺旋的转变。此外，通过结合盐桥和金属配位构建了人工双链金属超分子螺旋聚合物。与基于盐桥的设计导向型双螺旋结构不同，我们意外地开发了一种带有低聚酚链的螺硼酸基双螺旋配合物。通过形成非对映体盐成功实现了双螺旋配合物的光学拆分。我们还意外地发现，由非常简单的重复单元组成的低聚间苯二酚在水中借助芳香相互作用自组装成双螺旋结构。此外，通过在链的两端引入手性取代基，可以实现双螺旋结构扭转方向的偏向。
