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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Strain-release electrophilic activation via E-cycloalkenones.
Joseph Moran1, Peter Dornan, André M Beauchemin
1Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, Canada, K1N 6N5.
Organic Letters
|September 6, 2007
Summary
Ultraviolet A (UVA) light efficiently forms 1,4-adducts from cyclic enones and nitrogen heterocycles. This reaction proceeds via strained E-cycloalkenone intermediates, demonstrating their electrophilic nature.
Area of Science:
- Organic photochemistry
- Reaction mechanisms
Background:
- Cyclic enones and nitrogen heterocycles are common organic compounds.
- Understanding their photochemical reactions is crucial for synthetic chemistry.
Purpose of the Study:
- To investigate the photochemical reaction between cyclic enones and nitrogen heterocycles.
- To elucidate the reaction mechanism and identify key intermediates.
Main Methods:
- Photochemical reactions induced by Ultraviolet A (UVA) irradiation.
- Low-temperature generation and trapping experiments.
- Nuclear Magnetic Resonance (1H NMR) spectroscopy for reaction monitoring.
Main Results:
- Efficient formation of 1,4-adducts observed under UVA irradiation.
- Evidence for the involvement of strained E-cycloalkenone intermediates.
- Demonstration of E-cycloalkenones as effective electrophiles.
Conclusions:
- UVA irradiation provides an efficient route to 1,4-adducts.
- Strained E-cycloalkenone intermediates play a key role in this photochemical transformation.
- E-cycloalkenones exhibit significant electrophilic character in these reactions.
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