Double Rotors with Fluxional Axles: Domino Rotation and Azide-Alkyne Huisgen Cycloaddition Catalysis

摘要

The simple preparation of the multicomponent devices [Cu-4(A)(2)](4+) and [Cu-2(A)(B)](2+), both rotors with fluxional axles undergoing domino rotation, highlights the potential of self-sorting. The concept of domino rotation requires the interconversion of axle and rotator, allowing the spatiotemporal decoupling of two degenerate exchange processes in [Cu-4(A)(2)](4+) occurring at 142 kHz. Addition of two equiv of B to rotor [Cu-4(A)(2)](4+) afforded the heteromeric two-axle rotor [Cu-2(A)(B)](2+) with two distinct exchange processes (64.0 kHz and 0.55 Hz). The motion requiring a pyridine -> zinc porphyrin bond cleavage is 1.2x10(5) times faster than that operating via a terpyridine ->[Cu(phenAr(2))](+) rupture. Finally, both rotors are catalysts due to their copper(I) content. The fast domino rotor (142 kHz) was shown to suppress product inhibition in the catalysis of the azide-alkyne Huisgen cycloaddition.