Interconversion between [5]Pseudorotaxane and [3]Pseudorotaxane by Pasting/Detaching Two Axle Molecules

• DOI: 10.1021/jo201441r
• Publication Date: 2011-09-28T18:22:23Z
• Authors: Zhi-Jun Zhang; Heng-Yi Zhang; Ling Chen; Yu Liu
• Keywords: 01 natural sciences; 0104 chemical sciences

An acceptor-donor-acceptor-type linear molecule 1(2+) containing one electron-rich naphthoxy (NP) unit and two monocharged viologen (MCV) units was synthesized. Through the noncovalent interaction of cucurbit[8]uril (CB[8]) with one NP and one MCV in 1(2+), we first obtained a [2]pseudorotaxane ([1(2+)]⊂CB[8]), and the excess CB[8] included simultaneously the two bare MCV units of two [2]pseudorotaxanes to form a [5]pseudorotaxane ([1(2+)](2)⊂[CB[8]](3)). Its transformation to [3]pseudorotaxane was achieved through detaching the two axle molecules in the presence of acid, and then the addition of base may result in a reversible switch between two different pseudorotaxanes. This novel methodology elongating reversibly linear molecules by noncovalent interactions will benefit the development of stimuli-responsive functional molecular devices.