Electrochemical Generation of an Open-Shell Gold(III)-Dithiolene Porous Coordination Polymer

Abstract

Controlling the oxidation state of redox-active ligands during the assembly of Porous Coordination Polymers (PCPs) is a key challenge toward the design of electronically functional frameworks. Herein, we report a galvanostatic solvothermal strategy that enables the in situ electrochemical generation of an open-shell gold(III) bis(dithiolene) ligand during the formation of the network. The anionic tetrabenzoate-functionalized precursor undergoes anodic oxidation under constant current conditions, allowing precise control of the ligand's electronic state during the assembly of the framework. Magnetic measurements reveal regular S = 1/2 antiferromagnetic chains arising from one unpaired electron per Au(III)-dithiolene unit, while the room-temperature conductivity is comparable to that of closed-shell analogues, the charge transport proceeding through a Mott-insulating regime rather than a band-gap-activated mechanism, in agreement with band structure calculations. This electrochemical programming approach provides a general route to open-shell PCPs with electronically correlated ground states.