Macromolecular [2]Rotaxanes: Effective Synthesis and Characterization

Daisuke Aoki; Satoshi Uchida; Kazuko Nakazono; Yasuhito Koyama; Toshikazu Takata

doi:10.1021/mz400197d

Macromolecular [2]Rotaxanes: Effective Synthesis and Characterization

ACS Macro Lett. 2013 Jun 18;2(6):461-465. doi: 10.1021/mz400197d. Epub 2013 May 13.

Authors

Daisuke Aoki¹, Satoshi Uchida¹, Kazuko Nakazono¹, Yasuhito Koyama¹, Toshikazu Takata¹

Affiliation

¹ Department of Organic and Polymeric Materials, Tokyo Institute of Technology, 2-12-1 (H-126), Ookayama, Meguro-ku, Tokyo 152-8552, Japan.

PMID: 35581797
DOI: 10.1021/mz400197d

Abstract

Macromolecular [2]rotaxanes, which consist of a polymer chain threading into a wheel component, were synthesized in high yield and with high purity. The synthesis was achieved by the ring-opening polymerization (ROP) of δ-valerolactone (VL) using a hydroxyl-terminated pseudorotaxane as an initiator with diphenyl phosphate as a catalyst in dichloromethane at room temperature. The ¹H NMR, gel permeation chromatography (GPC), and MALDI-TOF-MS measurements of the resulting poly(δ-valerolactone)s clearly indicate the presence of the rotaxane structure with the polymer chain, confirming that the diphenyl phosphate-catalyzed ROP of VL proceeds without deslippage of the wheel component. The obtained macromolecular [2]rotaxane was acetylated to afford a nonionic macromolecular [2]rotaxane, in which only one wheel component is movable from one end to another along the polymer chain.