1098226-80-2Relevant academic research and scientific papers
Transition metal(II)-salen and -salophen macrocyclic complexes for rotaxane formation: Syntheses and crystal structures
Narita, Mamiko,Yoon, Il,Aoyagi, Masaru,Goto, Midori,Shimizu, Toshimi,Asakawa, Masumi
, p. 4229 - 4237 (2007)
We used a threading-followed-by-shrinking approach to prepare [2]rotaxanes possessing nickel(II)-salen and -salophen moieties. Reactions of macrocycles incorporating salen and salophen moieties with secondary dialkylammonium salts, followed by the addition of aqueous sodium sulfate, afforded the corresponding pseudorotaxanes; subsequent addition of nickel acetate shrank the effective size of the macrocycles to give the respective [2]rotaxanes. We obtained a [2]rotaxane possessing a salen unit in remarkably high yields - even in a polar solvent - indicating that the threading- followed-by-shrinking and salen-ring-opening-and-closing approaches occurred together. In addition, we expanded the threading- followed-by-shrinking approach to prepare a [2]rotaxane and a bis[2]rotaxane comprising two palladium(II)-salophen moieties linked in a bis-macrocycle and one and two secondary dialkylammonium salts, respectively. Furthermore, we prepared a tetraphenylporphyrin rhodium(III) chloride [Rh(TPP)Cl]-stoppered [2]rotaxane comprising a palladium(II)-salophen macrocycle and a pyridyl-terminated thread-like ion coordinated to the rhodium(III) center, which has potential as a next-generation molecular machine exhibiting catalytic function. Wiley-VCH Verlag GmbH & Co. KGaA, 2007.
