A dynamic silver(I)-loaded [2]rotaxane shuttle ( = 135 kHz) was converted allosterically into a conformationally restricted [2]rotaxane due to the creation of a bulky imine in the center of the axle component. Only the dynamic silver(I)-loaded [2]rotaxane was able to catalyze a 6--cyclization reaction, whereas the static one was catalytically quiet. The mechanism of catalyst deactivation was elucidated.
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