An asymmetric assembly of spirooxindole dihydropyranones through a direct enantioselective organocatalytic vinylogous aldol-cyclization cascade reaction of 3-alkylidene oxindoles with isatins.
نویسندگان
چکیده
A highly enantioselective organocatalytic vinylogous aldol-cyclization cascade reaction of 3-alkylidene oxindoles to isatins has been achieved by using bifunctional organocatalysts. The unexpected intramolecular lactonization which follows the initial aldol reaction, leading to the cleavage of the oxindole ring and generation of enantioenriched spirooxindole dihydropyranones in good to excellent yields with high enantioselectivities.
منابع مشابه
Asymmetric synthesis of a structurally and stereochemically complex spirooxindole pyran scaffold through an organocatalytic multicomponent cascade reaction.
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ورودعنوان ژورنال:
- Chemical communications
دوره 52 11 شماره
صفحات -
تاریخ انتشار 2016