Open AccessRemote Control of the Synthesis of a [2]Rotaxane and its Shuttling via Metal‐Ion Translocation
Author(s) -
Paul Indrajit,
Ghosh Amit,
Bolte Michael,
Schmittel Michael
Publication year - 2019
Publication title -
chemistryopen
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.644
H-Index - 29
ISSN - 2191-1363
DOI - 10.1002/open.201900293
Subject(s) - rotaxane , metal ions in aqueous solution , copper , chemistry , zinc , ion , metal , fluorescence , photochemistry , molecule , organic chemistry , supramolecular chemistry , physics , quantum mechanics
Abstract Remote control in an eight‐component network commanded both the synthesis and shuttling of a [2]rotaxane via metal‐ion translocation, the latter being easily monitored by distinct colorimetric and fluorimetric signals. Addition of zinc(II) ions to the red colored copper‐ion relay station rapidly liberated copper(I) ions and afforded the corresponding zinc complex that was visualized by a bright sky blue fluorescence at 460 nm. In a mixture of all eight components of the network, the liberated copper(I) ions were translocated to a macrocycle that catalyzed formation of a rotaxane by a double‐click reaction of acetylenic and diazide compounds. The shuttling frequency in the copper‐loaded [2]rotaxane was determined to k 298 =30 kHz (Δ H ≠ =62.3±0.6 kJ mol −1 , Δ S ≠ =50.1±5.1 J mol −1 K −1 , Δ G ≠ 298 =47.4 kJ mol −1 ). Removal of zinc(II) ions from the mixture reversed the system back generating the metal‐free rotaxane. Further alternate addition and removal of Zn 2+ reversibly controlled the shuttling mode of the rotaxane in this eight‐component network where the ion translocation status was monitored by the naked eye.