Organic chemistry. Practical olefin hydroamination with nitroarenes
Jinghan Gui1, Chung-Mao Pan1, Ying Jin1
1Department of Chemistry, Scripps Research Institute, La Jolla, CA 92037, USA.
Science (New York, N.Y.)
|May 23, 2015
Summary
This study introduces a new method for synthesizing secondary amines from olefins and nitro(hetero)arenes. The efficient and chemoselective process tolerates various functional groups, offering a versatile alternative for amine synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Amine synthesis and functionalization are crucial in various chemical applications.
- Existing methods for aryl amine synthesis have limitations in substrate scope and functional group tolerance.
Purpose of the Study:
- To develop a novel, efficient, and chemoselective method for synthesizing secondary amines.
- To utilize readily available feedstock chemicals like olefins and nitro(hetero)arenes.
Main Methods:
- A new synthetic protocol involving the reaction of olefins with nitro(hetero)arenes.
- Exploration of a presumed radical-mediated pathway for amine formation.
- Screening of over 100 substrate combinations to assess reaction scope and functional group tolerance.
Main Results:
- Successful synthesis of secondary amines via a formal olefin hydroamination.
- High chemoselectivity achieved, enabling the synthesis of sterically hindered amines.
- Demonstrated tolerance of numerous unprotected functional groups, including alcohols, amines, and boronic acids.
- Orthogonality to established methods like Buchwald-Hartwig and Ullmann couplings, tolerating aryl halides and carbonyl compounds.
Conclusions:
- The developed protocol offers a simple, operationally straightforward, and versatile route to secondary amines.
- This method expands the toolkit for amine synthesis, particularly for complex molecules with sensitive functional groups.
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