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Solid-phase Synthesis of [4.4] Spirocyclic Oximes

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Published on: February 6, 2019

Stereoselective Electrophilic Cyclization.

Akira Sakakura¹, Kazuaki Ishihara²

¹Graduate School of Natural Science and Technology, Okayama University, 3-1-1 Tsushima-naka, Kita-ku, Okayama, 700-8530, Japan.

Chemical Record (New York, N.Y.)

|July 7, 2015

Summary

This summary is machine-generated.

Researchers designed chiral Lewis base catalysts for enantioselective cyclizations of unactivated alkenes. These catalysts enable efficient synthesis of valuable building blocks through iodo-, protocyclizations, and bromocyclizations.

Keywords:

Lewis bases asymmetric synthesis electrophilic cyclization lactonization organocatalysis

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Published on: February 7, 2019

Area of Science:

Organic Chemistry
Catalysis
Synthetic Chemistry

Background:

Electrophilic cyclizations of unactivated alkenes are crucial for synthesizing valuable molecular building blocks.
Developing enantioselective methods for these transformations remains a significant challenge in organic synthesis.

Purpose of the Study:

To describe the rational design of monofunctionalized chiral Lewis base catalysts.
To achieve enantioselective iodo- and protocyclizations of unactivated alkenes.
To develop cooperative catalysts for stereoselective electrophilic bromocyclizations.

Main Methods:

Design and synthesis of novel chiral Lewis base catalysts.
Application of catalysts in enantioselective iodo-, proto-, and bromocyclizations.
Utilizing phosphite-urea cooperative catalysis for bromocyclizations.

Main Results:

Successfully developed monofunctionalized chiral Lewis base catalysts for enantioselective cyclizations.
Demonstrated the utility of these catalysts in the synthesis of complex molecules.
Designed effective nucleophilic phosphite-urea cooperative catalysts for stereoselective electrophilic bromocyclizations.

Conclusions:

The developed chiral Lewis base catalysts provide efficient access to enantiomerically enriched products from unactivated alkenes.
Cooperative catalysis offers a promising strategy for stereoselective electrophilic bromocyclizations.
This work advances the field of asymmetric catalysis for alkene functionalization.