95246-98-3Relevant articles and documents
A copper-based shuttling [2]rotaxane with two bidentate chelates in the axis: Steric control of the motion
Collin, Jean-Paul,Durola, Fabien,Lux, Jacques,Sauvage, Jean-Pierre
, p. 34 - 43 (2011/01/06)
Contrary to most of the other molecular machines based on copper-complexed catenanes or rotaxanes made and investigated in Strasbourg, the present report is dealing with a molecular shuttle for which the copper centre is complexed to two bidentate chelates, regardless of the state of the shuttle. In other words, the axis contains a sterically hindering bidentate chelate, namely a 2,9-diphenyl-1,10-phenanthroline (dpp) derivative, and another but less hindering bidentate chelate, 2,2′-bipyridine (bipy). The synthesis of the [2]rotaxane involves 15 individual chemical steps, excluding the preparation of the macrocyclic component of the [2]rotaxane. The threaded macrocycle is a 39-membered ring which incorporates an endocyclic but non sterically hindering chelate of the 8,8′-diphenyl-3,3′-biisoquinoline family (dpbiiq). The electrochemically-induced gliding motion of the copper-complexed ring from the dpp "station" to the bipy "station" and vice versa is fast on the cyclic voltammetry timescale (milliseconds). The copper(i) state is preferably located on the dpp unit whereas, by oxidising the copper(i) centre to its divalent state, the translation motion takes place to afford the thermodynamically most stable state now involving the bipy chelate.
Topological Kinetic Effects: Complexation of Interlocked Macrocyclic Ligands by Cationic Species
Albrehct-Gary, Anne-Marie,Dietrich-Buchecker, Christiane,Saad, Zeinab,Sauvage, Jean-Pierre
, p. 1467 - 1472 (2007/10/02)
Complexation of kinetic studies of various metal cations by a catenand have been performed.For comparison, the properties of some related open chain or monocyclic ligands have also been examined.Copper(I) and silver(I) catenate formation obeys a classical second-order rate law.The same is true for the model ligands examined, m-30 and dap.For Cu(dap)2+, the rate-limiting step corresponds to the formation of the bis-chelate complex from the monochelated one.On the other hand, Li+, Cd2+, Zn2+, and Co2+ catenates are formed in two distinct steps.The first process is second order, and it is likely to be the binding of the metallic cation to one of the chelating subunits.The second step is more intriguing.It does not depend on the metal concentration, and it might correspond to the gliding motion of one ring within the other while the second chelate fragment attempts to coordinate to the metal center.