Phosphine-catalyzed regioselective Michael addition to allenoates.
نویسندگان
چکیده
The first phosphine catalysed Michael addition of arylcyanoacetates to allenoates has been developed, and the β-selective products with a quaternary center were obtained in excellent yields. This unusual regioselectivity may open new opportunities to access interesting molecular structures.
منابع مشابه
Phosphine-containing Lewis base catalyzed cyclization of benzofuranone type electron-deficient alkenes with allenoates: a facile synthesis of spirocyclic benzofuranones.
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The triphenylphosphine-catalyzed formal [3 + 2] cycloaddition of allenoates and trifluoromethylketones was realized to give the corresponding dihydrofurans in good yields with excellent γ-regioselectivities. Hydrogenation of the dihydrofurans gave 2,4,4-trisubstituted tetrahydrofurans in good yields with exclusive cis-selectivities.
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ورودعنوان ژورنال:
- Chemical communications
دوره 51 90 شماره
صفحات -
تاریخ انتشار 2015