DYNAMIC BEHAVIOR OF A PSEUDO[N]POLYROTAXANE CONTAINING A BIPYRIDYL-BASED CYCLOPHANE - SPECTROSCOPIC OBSERVATIONS

We have shown by H-1 n.m.r. spectroscopy that the equilibrium between the cyclophane 5,37,39-octa-decaene]tetrakis(hexafluorophosphate) (1) and the polymer -oxynaphthyl)-1,4,7,11-tetroxaundecenyl))benzene)] (B: N)(n) is both rapid and heavily weighted toward the formation of the p seudo[n]polyrotaxane at room temperature in both MeCN-d(3) and DMSO-d( 6). At room temperature in DMSO-d(6) there is about one ring upon the polymer for each two repeat units of (B:N), at higher temperatures mor e repeat units are required to support one 1. At temperatures of ca. 2 43 K in MeCN-d(3) this system self assembles, by alpha stacking of the electron-rich polymer aromatics and the electron-poor cyclophane arom atics, into very ordered 'rods' that are on average about 10 nm long. (C) 1998 Elsevier Science Ltd. All rights reserved.