Organocatalytic asymmetric Michael addition of unprotected 3-substituted oxindoles to 1,4-naphthoquinone
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چکیده
منابع مشابه
Organocatalytic asymmetric Michael addition of unprotected 3-substituted oxindoles to 1,4-naphthoquinone
We reported the first example of organocatalytic Michael addition of unprotected 3-prochiral oxindoles 1 to 1,4-naphthoquinone. Quinidine derivative (DHQD)(2)PYR was found to be able to catalyze this reaction in up to 83% ee, with moderate to excellent yields. This method could be used for the synthesis of enantioenriched 3,3-diaryloxindoles, and the catalytic synthesis of which was unprecedented.
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An enantioselective α-oxyamination of unprotected 3-substituted oxindoles with nitrosobenzene catalyzed by tertiary amine-thiourea bifunctional organocatalysts has been developed and affords the corresponding 3-amino-2-oxindole derivatives in good yields and with moderate to excellent enantioselectivities (up to > 99.9 : 0.1 er when the product is isolated by direct filtration from the reaction...
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ژورنال
عنوان ژورنال: Beilstein Journal of Organic Chemistry
سال: 2012
ISSN: 1860-5397
DOI: 10.3762/bjoc.8.157