Catalytic Asymmetric Intramolecular [4+2] Cycloaddition of In Situ Generated ortho-Quinone Methides.
نویسندگان
چکیده
Herein, we describe the first catalytic asymmetric intramolecular [4+2] cycloaddition of in situ generated ortho-quinone methides. In the presence of a confined chiral imidodiphosphoric acid catalyst, various salicylaldehydes react with dienyl alcohols to give transient ortho-quinone methide intermediates, which undergo an intramolecular [4+2] cycloaddition to provide highly functionalized furanochromanes and pyranochromanes in excellent diastereoselectivity and enantioselectivity.
منابع مشابه
Asymmetric cycloadditions of o-quinone methides employing chiral ammonium fluoride precatalysts.
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ورودعنوان ژورنال:
- Angewandte Chemie
دوره 56 18 شماره
صفحات -
تاریخ انتشار 2017