Catalytically active nanorotor reversibly self-assembled by chemical signaling within an eight-component network

Abstract

A catalytically active three-component nanorotor is reversibly self-assembled and disassembled by remote control. When zinc(II) ions (2 equiv.) are added as an external chemical trigger to the mixture of transmitter [Cu(1)]⁺ and pre-rotor assembly [(S)·(R)], two equiv. of copper(I) ions translocate from [Cu(1)]⁺ to the two phenanthroline sites of [(S)·(R)]. As a result, [Zn(1)]²⁺ forms along with the three-component assembly [Cu₂(S)(R)]²⁺, which is both a nanorotor (k₂₉₈ = 46 kHz, ΔH^‡ = 49.1 ± 0.4 kJ mol⁻¹, ΔS^‡ = 9.5 ± 1.7 J mol⁻¹ K⁻¹) and a catalyst for click reactions (catalysis ON: A + B→AB). Removal of zinc from the mixture reverts the translocation sequence and thus commands disassembly of the catalytically active rotor (catalysis OFF). The ON/OFF catalytic cycle was run twice in situ in the full network.