Isolation of Anionic N-Heterocyclic Olefins and Their Versatile Reactivity.

Area of Science:

• Organic Chemistry
• Organometallic Chemistry

Background:

• N-heterocyclic olefins (NHOs) are versatile reagents in synthesis and catalysis.
• Existing methods for NHO synthesis are limited.

Purpose of the Study:

• To develop a novel synthetic route to anionic N-heterocyclic olefins (NHOs).
• To investigate the structure, stability, and reactivity of these anionic NHOs.

Main Methods:

• Formal ligand exchange reactions involving metalated ylides or diazomethanes with free carbenes.
• Spectroscopic (NMR, IR) and crystallographic analyses.
• Computational studies (DFT).

Main Results:

• A new synthetic approach to anionic NHOs was established.
• Anionic NHOs were found to have bent structures with delocalized anionic charge.
• Reactivity was observed at the central carbon, nitrogen atom, or Z substituent.
• A thermally induced rearrangement to N-heterocyclic imines was discovered.

Conclusions:

• The new method provides access to functionalized anionic NHOs.
• The electronic structure of anionic NHOs dictates their versatile reactivity.
• Anionic NHOs can rearrange to N-heterocyclic imines, expanding their synthetic utility.