Bicyclic guanidinium-catalyzed enantioselective phase-transfer alkylation: direct access to pyrroloindolines and furoindolines.
نویسندگان
چکیده
Highly enantioselective phase-transfer alkylation of 3-substituted-2-oxindoles with activated bromomethanes is disclosed with a broad substrate scope by using bicyclic guanidinium as a catalyst and a Lewis acid as the co-catalyst. The alkylation adducts are versatile intermediates to accomplish the syntheses of pyrroloindolines and furoindolines.
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ورودعنوان ژورنال:
- Chemical communications
دوره 49 84 شماره
صفحات -
تاریخ انتشار 2013