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Published on: August 12, 2019
Iron-catalyzed oxidative C(3)-H functionalization of amines
Noriaki Takasu1, Kounosuke Oisaki, Motomu Kanai
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Organic Letters
|April 13, 2013
Summary
Iron catalysis enables direct C(3)-H functionalization of tertiary arylamines through desaturative enamine formation. This method facilitates selective C-C bond formation, yielding unique nitrogen-containing molecules from cyclic and acyclic amines.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Tertiary arylamines are prevalent structural motifs in pharmaceuticals and materials.
- Direct functionalization of C-H bonds offers atom-economical synthetic routes.
- Selective activation of sp(3) C-H bonds in amines remains a synthetic challenge.
Purpose of the Study:
- To develop a novel iron-catalyzed method for direct dehydrogenative C(3)-functionalization of tertiary arylamines.
- To explore the scope and limitations of the developed reaction with various cyclic and acyclic amines.
- To demonstrate the utility of the synthesized products for creating diverse nitrogen-containing compounds.
Main Methods:
- Iron-catalyzed direct dehydrogenative coupling reaction.
- Activation of the sp(3) C(3)-H bond of tertiary arylamines.
- Catalytic desaturative enamine formation followed by C-C bond formation with nitro olefins.
Main Results:
- Successful Fe-catalyzed direct C(3)-functionalization of tertiary arylamines was achieved.
- The reaction demonstrated applicability to both cyclic and acyclic amine substrates.
- Position-selective C-C bond formation at the β-carbon was observed.
- The resulting products served as precursors for versatile nitrogen-containing molecules.
Conclusions:
- A novel and efficient iron-catalyzed method for C(3)-H functionalization of tertiary arylamines has been established.
- The developed protocol offers a strategic approach for synthesizing unique nitrogen-containing molecules.
- This methodology expands the toolkit for C-H activation and functionalization in organic synthesis.
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