Catch-Release System for Dosing and Recycling Silver(I) Catalyst with Status of Catalytic Activity Reported by Fluorescence.

The silver(I) catch-release system composed of nanoswitch 1 and the anthracene-appended crown ether 2 is infallibly driven by chemical triggers and ion transfer. Any state of the silver(I) translocation is self-reported by a ratiometric emission signature at 472 and 554 nm. In the self-sorted networked state I, the silver(I) ions are tightly shielded inside nanoswitch [Ag(1)]+ ("catch") so that their catalytic activity is zero while emission at 554 nm is maximum. Addition of zinc(II) releases silver(I) from [Ag(1)]+ and generates the catalytically active and fluorescent complex [Ag(2)]+. In this networked state II ("release") both catalytic activity and emission at 472 nm are maximum. Removal of the original trigger regenerates networked state I. ON/OFF control and recycling of catalyst was demonstrated over three in situ cycles.