1.3 V Inorganic Sequential Redox Chain with an All-Anionic Couple 1-/2- in a Single Framework

Area of Science:

• Organometallic Chemistry
• Inorganic Chemistry
• Electrochemistry

Background:

• The cobaltabis(dicarbollide) platform ([3,3'-Co(1,2-C2B9H11)2]-) offers numerous substitution sites for tuning electrochemical properties.
• Controlled modification of electrochemical potentials is crucial for developing advanced materials, but often challenging in existing systems like ferrocene.

Purpose of the Study:

• To demonstrate a regioselective and stepwise chlorination method for tuning the electrochemical potential of the cobaltabis(dicarbollide) system.
• To achieve a broad electrochemical potential tuning range (1.3 V) through controlled substitution.

Main Methods:

• Sequential chlorination of the cobaltabis(dicarbollide) platform using sulfuryl chloride.
• Synthesis starting from the protonated form of [Co(C2B9H11)2]-.
• Comprehensive characterization including spectroscopic, crystallographic, and electrochemical methods.

Main Results:

• Achieved linear and sequential tuning of electrochemical potentials with increasing numbers of chloro substituents.
• Synthesized new chlorinated cobaltabis(dicarbollide) derivatives, expanding the known series.
• Developed an efficient and rapid method for synthesizing highly chlorinated derivatives.

Conclusions:

• Stepwise chlorination of cobaltabis(dicarbollide) provides a controlled route to tune electrochemical potentials over a significant range.
• The developed method is facile and utilizes less hazardous reagents.
• Further extension of the potential range by changing the central metal to iron is proposed.