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Updated: Feb 4, 2026
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
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Enantioselective Michael Spirocyclization of Palladium Enolates
Christian Santiago Strong1, Peng-Jui Chen1, Sanzhar Bissenali1
1The Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States.
ACS Catalysis
|February 2, 2026
Summary
This study introduces a novel Michael spirocyclization reaction using palladium enolates. The method efficiently creates complex molecular structures with adjacent quaternary and tertiary stereocenters, advancing synthetic organic chemistry.
Area of Science:
- Organic Chemistry
- Catalysis
- Stereoselective Synthesis
Background:
- Michael reactions are fundamental in organic synthesis.
- Creating adjacent all-carbon quaternary and tertiary stereocenters is challenging.
- Palladium catalysis offers powerful tools for C-C bond formation.
Purpose of the Study:
- To develop an enantioselective and diastereoselective Michael spirocyclization.
- To synthesize molecules with adjacent all-carbon quaternary and tertiary stereocenters.
- To explore the generation of diverse tricyclic scaffolds.
Main Methods:
- Utilized tetrasubstituted palladium enolates.
- Performed enantioselective and diastereoselective Michael spirocyclization.
- Employed subsequent cyclization reactions.
- Investigated reaction mechanisms using quantum mechanics calculations.
Main Results:
- Achieved formation of adjacent all-carbon quaternary and tertiary stereocenters.
- Obtained good yields, diastereoselectivity (dr), and enantioselectivity (ee).
- Synthesized a diverse range of tricyclic scaffolds.
- Elucidated the mechanism and origins of stereoselectivity.
Conclusions:
- The developed Michael spirocyclization is a powerful method for stereoselective synthesis.
- This reaction provides access to complex molecular architectures.
- Quantum mechanics calculations offer insights into stereochemical control.
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