Fast redox-triggered shuttling motions in a copper rotaxane based on a phenanthroline–terpyridine conjugate

Abstract

Fast shuttling motions in solution have been observed by cyclic voltammetry in a Cu(I/II)-based [2] rotaxane. In the reported system, the different coordination preferences of both copper oxidation states are exploited to promote the electrochemically-triggered gliding of the ring from a tetra to a pentacoordinated site and vice versa. The thread of this rotaxane consists of a tridentate 2,2':6',2''-terpyridine chelating unit directly bonded through its 5-position to the 3-position of the bidentate 1,10-phenanthroline unit. This distribution reduces to a minimum the distance between the two coordination sites and lessens the congestion around the tetrahedral environment. These two factors have been demonstrated to highly increase the kinetics of the switching process. In addition, the electrochemical experiments carried out in different solvent mixtures evidenced the influence of the solvent on the shuttling mechanism.

Heteroleptic copper phenanthroline complexes in motion: From stand-alone devices to multi-component machinery

“…[ [5] Cu] 2+ reorganization was determined as k 298 = 2 s À1 (CH 2 Cl 2 / MeCN = 1:9). The solvent dependence was rather modest decreasing from k 298 = 1 s À1 at CH 2 Cl 2 /MeCN = 1:1 to k 298 = 0.6 s À1 at CH 2 Cl 2 / MeCN = 9:1 [90]. As the shuttling requires dissociation of the copper -phen macrocycle bond the acetonitrile seems to stabilize the copper (II) species in the gliding procedure.…”

“…This principle, somewhat modified, was used by the same authors to set up the fast shuttle [ [4] Cu (83)] + (see Fig. 38) [90]. Using cyclic voltammetry the [ [4] Cu] 2+ ?…”

6-Arylcoumarin as a Scaffold of Photofunctional Molecules with OFF–ON–OFF Type Regulation

“…Analytical HPLC for quantification of phenethylamine was carried out using a C18 reversed phase column on JASCO PU-2080 plus and JASCO FP-2025 plus. Compounds 5 and 6 were prepared according to the literature procedure. , …”

“…Compounds 5 and 6 were prepared according to the literature procedure. 26,27 Preparation of Compounds. Preparation of 7.…”

Phenanthroline based rotaxanes: recent developments in syntheses and applications

“…Tatay, Gaviña and co-workers reported the synthesis of a novel [2]rotaxane which harbours an elongated and unsymmetrical axle component ( Scheme 6 ). 11 Synthesis of this rotaxane ensued from mono-stoppered axle 19, having a terminal alkyne functionality at the free end for further manipulation. Treatment of 19 with macrocyclic component 8 in the presence of Cu( i ) ion resulted in simultaneous threading of components to result in pseudorotaxane 20.…”