Well-Defined Aryl-Fe^II Complexes in Cross-Coupling and C-H Activation Processes

Area of Science:

• Organometallic Chemistry
• Iron Catalysis
• Macrocyclic Ligand Design

Background:

• Aryl-iron species are vital intermediates in iron-catalyzed cross-coupling and C-H functionalization.
• Stabilizing these reactive intermediates is key to advancing iron catalysis.

Purpose of the Study:

• To explore the intrinsic organometallic reactivity of iron within a tetradentate N3C macrocyclic ligand.
• To synthesize and characterize novel aryl-iron complexes and investigate their catalytic applications.

Main Methods:

• Synthesis of aryl-FeII complexes using light irradiation and moderate heating.
• Characterization through spectroscopic methods and X-ray crystallography.
• Investigation of C-H activation, biaryl C-C coupling, and cross-coupling reactions.

Main Results:

• Successful synthesis of aryl-FeII complexes [FeII(Br)(L)(CO)] and [FeII(L)(CO)2]Br.
• Characterization of rare low-spin diamagnetic iron species.
• Demonstration of C-H activation and cross-coupling reactions.

Conclusions:

• The tetradentate N3C macrocyclic ligand effectively stabilizes aryl-Fe species.
• These iron complexes exhibit intrinsic reactivity applicable to C-H functionalization and cross-coupling reactions.
• The study provides insights into the fundamental reactivity of iron in organometallic catalysis.