[2+3] Cycloadditions Between Nitroalkenes and Camphor-Derived Oxazoline N-Oxides and Radical Denitration of the Adducts

Abstract

[2+3] Cycloadditions between camphor-derived oxazoline N-oxide 2 and nitroalkenes 3a-f afforded stereoselectively adducts 4a-f. Radical denitration followed by acidic hydrolysis gave rise to anti-aldols 8a,b. The radical intermediate was also trapped by a suitable alkene, giving rise to a single stereoisomer.

Key words

cycloaddition - asymmetric synthesis - radical

References

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15

Scheme 10 Note: this special purification procedure applies when­ever phenyl-substituted nitroalkenes are used in the cycloaddition (Scheme 10).