Phosphine-containing Lewis base catalyzed cyclization of benzofuranone type electron-deficient alkenes with allenoates: a facile synthesis of spirocyclic benzofuranones.
نویسندگان
چکیده
A regioselective [3 + 2] cycloaddition of benzofuranone type active olefins with allenoates catalyzed by trivalent phosphines has been developed, which provided an easy access to enriched functionalized spirocyclic benzofuranones. The reactions accommodated a number of benzofuranone type electron-deficient olefins and allenoates to give the desired 3-spirocyclopentane benzofuran-2-ones or 2-spirocyclopentane benzofuran-3-ones with moderate to excellent yields (up to 99%) and moderate to good regioselectivities (up to 11:1).
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 11 9 شماره
صفحات -
تاریخ انتشار 2013