Related Experiment Video
Updated: Jul 20, 2026

Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Remarkably stable chiral zirconium complexes for asymmetric Mannich-type reactions
Kowichiro Saruhashi1, Shu Kobayashi
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, The HFRE Division, ERATO, Japan Science Technology Agency (JST), Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
New chiral zirconium catalysts enable highly selective asymmetric Mannich-type reactions. These isolable, reusable catalysts offer high yields and stereoselectivities, simplifying complex chemical synthesis.
Area of Science:
- Organometallic Chemistry
- Asymmetric Catalysis
Background:
- Chiral catalysts are essential for stereoselective synthesis.
- Developing stable and reusable catalysts remains a challenge.
Purpose of the Study:
- To develop isolable, air-stable, and highly selective chiral zirconium catalysts.
- To investigate their efficiency in asymmetric Mannich-type reactions.
Main Methods:
- Synthesis of chiral zirconium catalysts.
- Asymmetric Mannich-type reactions using imines and silicon enolates.
- Catalyst recovery and reuse experiments.
- X-ray crystallography and NMR spectroscopy for structural analysis.
Main Results:
- The developed zirconium catalysts demonstrated high yields and stereoselectivities in Mannich-type reactions.
- Catalysts were isolable, air-stable, and reusable without significant activity loss.
- X-ray analysis of zirconium single crystals confirmed catalytic performance.
- NMR studies indicated the formation of a common key intermediate despite structural variations.
Conclusions:
- Stable, reusable chiral zirconium catalysts are effective for asymmetric Mannich-type reactions.
- These catalysts offer a practical approach to synthesizing chiral adducts with high selectivity.
- Further investigation into the catalytic mechanism is warranted.
More Related Videos
08:25Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks (MOFs)
Published on: January 17, 2020
09:45Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Related Concept Videos
E1 Reaction: Stereochemistry and Regiochemistry
Prochirality
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
Radical Halogenation: Stereochemistry
Halogenation to form a new chiral center:
Regioselectivity of Electrophilic Additions to Alkenes: Markovnikov's Rule
The hydrohalogenation of an unsymmetrical alkene can yield two haloalkane products, depending on which vinylic carbon takes up the halogen. However, one product usually predominates, where hydrogen adds to the vinylic carbon bearing the...