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Solid-state asymmetric photochemical studies using the ionic chiral auxiliary approach.
1The State Key Lab of Urban Water Resource and Environment, National Engineering Research Center of Urban Water Resource & The Academy of Fundamental and Interdisciplinary Science, Harbin Institute of Technology, P. O. Box 3026, 2 Yikuang Street, Harbin, Heilongjiang, 150080 (P.R. China), Fax: (+86) 451-86402588.
Chemistry, an Asian Journal
|October 16, 2009
Summary
The ionic chiral auxiliary method enables highly effective asymmetric photochemical synthesis in the solid state. This technique achieves excellent enantiomeric excesses, up to 99%, for key photoreactions.
Area of Science:
- Organic Chemistry
- Photochemistry
- Asymmetric Synthesis
Background:
- The Scheffer group pioneered the ionic chiral auxiliary approach for asymmetric photochemical synthesis.
- Solid-state applications have shown significant promise for enantioselective reactions.
Purpose of the Study:
- To review the application of the solid-state ionic chiral auxiliary technique in asymmetric photochemistry.
- To highlight its success in various photorearrangements.
Main Methods:
- Utilizing ionic chiral auxiliaries in the solid state to control photochemical reaction stereochemistry.
- Applying the method to Norrish type II reactions, di-pi-methane photorearrangements, and retro-Claisen photorearrangements.
Main Results:
- Achieved high enantiomeric excesses, up to 99%, in solid-state photochemical reactions.
- Demonstrated the versatility of the ionic chiral auxiliary approach across different reaction types.
Conclusions:
- The solid-state ionic chiral auxiliary method is a powerful tool for asymmetric photochemical synthesis.
- This approach offers high stereocontrol and broad applicability to important organic photoreactions.
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