Aryl-Fluoride Bond-Forming Reductive Elimination from Nickel(IV) Centers

Area of Science:

• Organometallic Chemistry
• Fluorination Chemistry
• Catalysis

Background:

• Carbon-fluorine (C-F) bond formation is crucial in synthesizing pharmaceuticals and materials.
• Traditional fluorination methods often require harsh conditions or specialized reagents.
• Nickel catalysis offers a promising avenue for developing milder and more efficient fluorination strategies.

Purpose of the Study:

• To investigate the C(sp2)-F bond formation using pyridine- and pyrazole-ligated Ni(II) complexes.
• To explore the role of nickel intermediates in the fluorination process.
• To demonstrate the utility of Ni(IV) σ-aryl fluoride complexes in reductive elimination reactions.

Main Methods:

• Treatment of pyridine- and pyrazole-ligated Ni(II) σ-aryl complexes with Selectfluor.
• Spectroscopic detection and isolation of diamagnetic Ni(IV) σ-aryl fluoride intermediates.
• Analysis of the C(sp2)-F bond-forming reductive elimination pathway.

Main Results:

• Successful C(sp2)-F bond formation under mild conditions.
• Identification and characterization of Ni(IV) σ-aryl fluoride intermediates.
• Demonstration of Ni(IV) σ-aryl fluoride complexes participating in reductive elimination.

Conclusions:

• This study establishes a novel synthetic route for aryl fluorides via nickel catalysis.
• The findings highlight the participation of Ni(IV) intermediates in C-F bond formation.
• The developed method offers a mild and efficient approach to synthesizing fluorinated organic compounds.