Stereoselective Intramolecular [4 + 3] Cycloadditions of Nitrogen-Stabilized Chiral Oxyallyl Cations via Epoxidation of N-Tethered Allenamides
2003; American Chemical Society; Volume: 125; Issue: 42 Linguagem: Inglês
10.1021/ja030416n
ISSN1943-2984
AutoresHui Xiong, Jian Huang, Sunil K. Ghosh, Richard P. Hsung,
Tópico(s)Oxidative Organic Chemistry Reactions
ResumoThe first intramolecular [4 + 3] cycloaddition reaction using nitrogen-stabilized chiral oxyallyl cations that are tethered to furan or diene through the nitrogen atom is described here. Formation of these nitrogen-stabilized chiral oxyallyl cations is achieved by a chemoselective epoxidation of chiral allenamides via syringe pump addition of dimethyl dioxirane. The ensuing cycloaddition can be carried out with a range of different lengths for the tether, and high diastereoselectivities can be obtained when using chiral allenamides with shorter tethers.
Referência(s)