| Abstract
| - This paper describes the self-assembly of a new class of three-component dynamic [2]catenanes, whichare driven or stabilized by intramolecular hydrogen bonding, coordination, and electrostatic interaction.One of the component molecules 2, consisting of an aromatic oligoamide spacer and two peripheral zincporphyrin units, was designed to adopt a folded preorganized conformation, which is stabilized byconsecutive intramolecular three-centered hydrogen bonds. Component molecule 3 is a linear secondaryammonium bearing two peripheral pyridine units, which was designed to form a 1:1 complex with 24-crown-8 (5). The 1H NMR and UV−vis experiments in CDCl3−CD3CN (4:1 v/v) revealed that, due tothe preorganized U-shaped feature, 2 could efficiently bind 3 through the cooperative zinc−pyridinecoordination to generate highly stable 1:1 complex 2·3. Adding 5 to the 1:1 solution of 2 and 3 led tothe formation of dynamic three-component [2]catenane 2·3·5 as a result of the threading of 3 through 5.1H NMR studies indicated that in the 1:1:1 solution (3 mM) [2]catenane 2·3·5 was generated in 55%yield at 25 °C. The yield was increased with the reduction of the temperature and [2]catenane could beproduced quantitatively in a 1:1:2 solution ([2] = 3 mM) at −13 °C. Replacing 3 with 1,2-bis(4,4‘-bipyridinium)ethane (4) in the three-component solution could also give rise to similar dynamic [2]catenane 2·4·5 albeit in slightly lower yield.
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