Silver(I) Ion Assisted Assembly of One-Dimensional Polyrotaxanes Incorporating Cucurbit[6]uril

A pseudo-rotaxane, [(H2C6N3)(CB[6])](NO3)2·H2O (1), and three polyrotaxanes, [Ag(H2C6N3)(CB[6])](NO3)3·8H2O (2), [Ag(H2BDMN3)(CB[6])](NO3)3·10H2O (3), and [Ag(H2BDMN3)(CB[6])(H2O)][Ag(H2BDMN3)(CB[6])](ClO4)6·12H2O
(4), are prepared with N,N‘-bis(3-pyridylmethyl)-1,6-hexanediamine (C6N3) or N,N‘-bis(3-pyridylmethyl)-1,4-benzenedimethylamine
(BDMN3) incorporating cucurbit[6]uril (CB[6]) assisted by silver(I) ion. X-ray diffraction analyses reveal that polyrotaxanes 2, 3,
and 4 all have 1D linear chain structures with different shapes. Compounds 2 and 4 are square-wave shaped, while 3 is sawtooth-wave shaped. It is suggested that shapes of the 1D chains are mainly affected by flexibility of guest molecules, as well as the
counteranions. Weak interactions between host/guest and inter-psuedo-rotaxanes help to generate infinite 2D and 3D structures
from 1D chains of these polyrotaxanes.