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Millifluidics for Chemical Synthesis and Time-resolved Mechanistic Studies
Published on: November 27, 2013
Gold(I)-catalyzed stereoselective olefin cyclopropanation
Magnus J Johansson1, David J Gorin, Steven T Staben
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|December 22, 2005
Summary
A novel gold(I) complex catalyzes the cyclopropanation of olefins using propargyl esters. This method efficiently produces vinyl cyclopropanes with high enantioselectivity and cis-selectivity.
Area of Science:
- Organometallic Chemistry
- Asymmetric Catalysis
Background:
- Gold(I) complexes are effective catalysts for carbene transfer reactions.
- Propargyl esters can serve as precursors for gold(I)-carbenes.
Purpose of the Study:
- To develop a gold(I)-catalyzed cyclopropanation of olefins.
- To achieve enantioselective synthesis of vinyl cyclopropanes.
Main Methods:
- Triphenylphosphinegold(I)-catalyzed cyclopropanation reaction.
- Utilized propargyl esters as gold(I)-carbene precursors.
- Employed a DTBM-SEGPHOS gold(I) complex for enantioselective catalysis.
Main Results:
- Successful cyclopropanation of olefins was achieved.
- The DTBM-SEGPHOS gold(I) catalyst enabled enantioselective vinyl cyclopropane synthesis.
- High enantiomeric excess (up to 94% ee) and cis-selectivity were obtained.
Conclusions:
- A novel and efficient gold(I)-catalyzed cyclopropanation method was established.
- The developed protocol provides access to valuable vinyl cyclopropane derivatives.
- The DTBM-SEGPHOS ligand is crucial for achieving high stereoselectivity in this transformation.
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