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Updated: Aug 5, 2026
09:37
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Sulfilimines Are Azide Alternatives for Nitrene-Mediated Aromatic C-to-N Transmutation
Mikus Puriņš1, Jeongyeon Hwang1, Mark D Levin1
1Department of Chemistry, University of Chicago, Chicago, Illinois60637, United States.
Journal of the American Chemical Society
|July 27, 2026
Summary
Sulfilimines offer a safer, more efficient alternative to hazardous azide precursors for carbon-to-nitrogen atom transmutation. These photoactivatable nitrene precursors enable practical nitrogen incorporation into complex molecules without compromising reaction outcomes.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
- Chemical Biology
Background:
- Carbon-to-nitrogen (C-to-N) atom transmutation enables direct nitrogen incorporation.
- Current methods rely on azide precursors, posing toxicity and safety risks.
- Widespread adoption is limited by the hazards associated with azides.
Purpose of the Study:
- To introduce sulfilimines as safe and effective photoactivatable nitrene precursors.
- To demonstrate sulfilimines as drop-in replacements for azides in C-to-N transmutation reactions.
- To establish a practical, azide-free platform for C-to-N skeletal editing.
Main Methods:
- Utilized sulfilimines as photoactivatable nitrene precursors.
- Applied sulfilimines across three distinct C-to-N transmutation reactions.
- Investigated precursor synthesis from various functional handles, including C-H functionalization.
Main Results:
- Sulfilimine-mediated reactions showed comparable or superior efficiency to azide-based methods.
- Observed reduced reaction times and improved scalability with sulfilimine precursors.
- Demonstrated successful C-to-N replacement on complex molecular scaffolds.
Conclusions:
- Sulfilimines are practical, azide-free alternatives for C-to-N atom transmutation.
- This approach enhances safety and efficiency in nitrogen incorporation.
- Facilitates broader implementation of atom transmutation in synthetic chemistry.
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