Networking Nanoswitches for ON/OFF Control of Catalysis

Abstract

The nanoswitches 1 and 2 are interdependently linked in so-called network states (NetStates). In NetState I, defined by presence of [Cu(1)]⁺ and 2, the organocatalyst N-methylpyrrolidine catalyzes a conjugate addition. Addition of iron(II) ions as an external chemical trigger to NetState I discharges Cu⁺ from [Cu(1)]⁺. The liberated copper(I) ion acts as a second messenger and changes the toggling state at nanoswitch 2. The resulting nanoswitch [Cu(2)]⁺ captures the catalytically active species from solution and the conjugate addition is turned OFF. Removal of the original trigger reverses the sequence and turns catalysis ON. The ON/OFF catalytic cycle was run three times in situ.