A Redox-Switchable, Allosteric Coordination Complex

J Am Chem Soc. 2018 Nov 7;140(44):14590-14594. doi: 10.1021/jacs.8b09321. Epub 2018 Oct 26.

Abstract

A redox-regulated molecular tweezer complex was synthesized via the weak-link approach. The PtII complex features a redox-switchable hemilabile ligand (RHL) functionalized with a ferrocenyl moiety, whose oxidation state modulates the opening of a specific coordination site. Allosteric regulation by redox agents gives reversible access to two distinct structural states-a fully closed state and a semi-open state-whose interconversion was studied via multinuclear NMR spectroscopy, cyclic voltammetry, and UV-vis-NIR spectroscopy. Two structures in this four-state system were further characterized via SCXRD, while the others were modeled through DFT calculations. This fully reversible, RHL-based system defines an unusual level of electrochemical control over the occupancy of a specific coordination site, thereby providing access to four distinct coordination states within a single system, each defined and differentiated by structure and oxidation state.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.