Nitrene-mediated intermolecular N-N coupling for efficient synthesis of hydrazides
Hao Wang1, Hoimin Jung2,3, Fangfang Song1
1State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin, China.
Nature Chemistry
|March 23, 2021
Summary
This study introduces a new method for creating N-N bonds using nitrene intermediates, dioxazolones, and arylamines. This efficient synthesis of hydrazides utilizes iridium or iron catalysis, offering a valuable tool for organic chemistry.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Nitrogen-nitrogen (N-N) linkages are crucial in numerous natural products, imparting unique structural and functional characteristics.
- Despite extensive research on carbon-nitrogen (C-N) bond formation, the development of intermolecular N-N coupling reactions remains a significant challenge in synthetic chemistry.
Purpose of the Study:
- To develop a novel and efficient method for intermolecular N-N coupling.
- To synthesize diverse hydrazides from readily accessible carboxylic acid and amine precursors.
- To explore the utility of nitrene-mediated reactions catalyzed by iridium or iron.
Main Methods:
- Nitrene-mediated intermolecular N-N coupling reaction.
- Utilized dioxazolones and arylamines as key substrates.
- Employed iridium (Ir) or iron (Fe) catalysis to facilitate the N-N bond formation.
Main Results:
- Successfully synthesized various hydrazides through an efficient and straightforward protocol.
- Iridium catalysis generally provided higher yields compared to iron catalysis.
- Iron catalysis demonstrated superior performance for sterically hindered dioxazolones derived from α-substituted carboxylic acids.
Conclusions:
- The developed nitrene-mediated coupling offers a facile route to hydrazides.
- Catalyst choice (Ir vs. Fe) impacts reaction efficiency, particularly with sterically demanding substrates.
- Mechanistic insights suggest electrophilic nitrene intermediates and hydrogen bonding play key roles in N-N bond formation.
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