Stereoselective intramolecular [4 + 3] cycloadditions of nitrogen-stabilized chiral oxyallyl cations via epoxidation of N-tethered allenamides.
نویسندگان
چکیده
The 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.
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عنوان ژورنال:
- Journal of the American Chemical Society
دوره 125 42 شماره
صفحات -
تاریخ انتشار 2003