A Toggle Nanoswitch Alternately Controlling Two Catalytic Reactions

Reversible switching between two states of the triangular nanoswitch [Cu( 1 )]⁺ was accomplished by alternate addition of 2‐ferrocenyl‐1,10‐phenanthroline ( 2 ) and copper(I) ions. The two switching states regulate the binding and release of two distinct catalysts, piperidine and [Cu( 2 )]⁺, in a fully interference‐free manner and allow alternating on/off switching of two orthogonal catalytic processes. In switching state I, piperidine is released from the nanoswitch and catalyzes a Knoevenagel addition between 4‐nitrobenzaldehyde and diethyl malonate (ON‐1 and OFF‐2), while in state II the released [Cu( 2 )]⁺ catalyzes a click reaction between 4‐nitrophenylacetylene and benzylazide (OFF‐1 and ON‐2). Upon addition of one equivalent of 2 to the (OFF‐1 and ON‐2)‐state, both catalytically active processes are shut down (OFF‐1 and OFF‐2).