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Published on: October 30, 2018
Iridium complex-catalyzed allylic amination of allylic esters
1Department of Chemistry, Graduate School of Integrated Science, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama 236-0027, Japan. rtakeuch@yokohama-cu.ac.jp
Journal of the American Chemical Society
|September 27, 2001
Summary
Iridium complex catalysis enables efficient allylic amination of carbonates. Polar solvents like ethanol are crucial for high yields, offering superior selectivity compared to palladium catalysts.
Area of Science:
- Organometallic Chemistry
- Catalysis
- Organic Synthesis
Background:
- Allylic amination is a key transformation in organic synthesis.
- Developing efficient and selective catalytic methods is crucial.
- Previous methods often lack control over regioselectivity and stereoselectivity.
Purpose of the Study:
- To investigate iridium complex-catalyzed allylic amination of allylic carbonates.
- To explore the influence of solvents and reaction conditions on catalytic activity and selectivity.
- To establish a novel synthetic route for allylic amines with high selectivity.
Main Methods:
- Utilized iridium complex, specifically [Ir(COD)Cl](2) with P(OPh)(3) as a catalyst.
- Investigated the effect of various solvents, with a focus on polar solvents like ethanol.
- Examined the reaction with different allylic carbonate substrates and various primary and secondary amines.
Main Results:
- High yields and selectivities (up to 99%) were achieved for branched allylic amines using (E)-allylic carbonates.
- Selective monoallylation was observed with primary amines, preventing diallylation.
- Exclusive formation of alpha,alpha-disubstituted allylic amines from 1,1-disubstituted-2-propenyl acetates.
- High selectivity (up to 100%) for (Z)-linear allylic amines from (Z)-allylic carbonates, with no (E)-isomer formation.
- Demonstrated superior selectivity compared to similar palladium-catalyzed reactions.
Conclusions:
- Iridium catalysis provides a highly selective method for allylic amination of allylic carbonates.
- Polar solvents are essential for achieving high catalytic activity and yields.
- This method offers a valuable alternative for synthesizing diverse allylic amines with unprecedented selectivity.
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