N-Boryl Pyridyl Anion Chemistry

Area of Science:

• Organic Chemistry
• Heterocyclic Chemistry
• Catalysis

Background:

• Pyridine typically acts as an N-nucleophile and electron-deficient aromatic ring.
• Classical pyridine reactivity limits its synthetic utility.
• Developing electron-rich pyridine systems offers new chemical transformations.

Purpose of the Study:

• To describe an approach for umpolung reactivity of the pyridine ring.
• To introduce the N-boryl pyridyl anion (N-BPA) intermediate.
• To showcase new catalytic and derivatization reactions enabled by N-BPA.

Main Methods:

• In situ formation of N-boryl pyridyl anion (N-BPA) intermediates.
• Utilizing N-BPA's dual reactivity as an electron donor and nucleophile.
• Employing pyridine catalysts in redox and functionalization reactions.

Main Results:

• Developed a pyridine-catalyzed redox system for single-electron reductions via SET.
• Established a modular photoredox system with tunable redox properties.
• Demonstrated pyridine derivatization and umpolung transformations using N-BPA, including novel defluorinative and perfluoroalkylation reactions.

Conclusions:

• N-boryl pyridyl anion (N-BPA) exhibits unprecedented reactivity, enabling pyridine umpolung.
• This work expands pyridine chemistry with new redox catalysis and functionalization strategies.
• The findings are expected to inspire further research in heterocyclic chemistry.