A Modular Strategy for Expanding Electron-Sink Capacity in Noncanonical Cluster Assemblies

Area of Science:

• Inorganic Chemistry
• Organometallic Chemistry
• Electrochemistry

Background:

• Large multinuclear clusters are benchmarks for electron-sink behavior.
• Developing simpler molecules with similar electron-sink capacities is desirable.

Purpose of the Study:

• To develop a modular synthetic strategy for creating organometallic complexes with significant electron-sink capacity.
• To investigate the electron-sink properties of complexes assembled from Fe2(PPh2)2(CO)5 fragments.

Main Methods:

• Assembly of organometallic complexes using a common Fe2(PPh2)2(CO)5 fragment around aromatic cores.
• Varying the number of isocyanide functional groups on the aromatic core (one, two, or three).
• Electrochemical analysis to determine electron-sink capacities and reduction potentials.

Main Results:

• Successfully synthesized complexes with electron-sink capacities of two, four, and six electrons.
• The six-electron complex rivals the electron-sink capacity of large multinuclear clusters.
• The hexaanionic state was achieved over a narrow potential window, attributed to potential inversions.

Conclusions:

• A modular approach enables the construction of "noncanonical clusters" with tunable, high electron-sink capacities.
• These complexes exhibit redox properties similar to large clusters but possess simpler structures.
• This strategy offers a new avenue for designing electroactive materials.