Enantioselective synthesis of spiro[4H-pyran-3,3′-oxindole] derivatives catalyzed by cinchona alkaloid thioureas: Significant water effects on the enantioselectivity
نویسندگان
چکیده
منابع مشابه
A clean and efficient synthesis of spiro[4H-pyran-oxindole] derivatives catalyzed by egg shell
Egg shell has been utilized as a natural, green, reusable and eco-friendly reagent for the synthesis of spiro[4H-pyran-oxindole] derivatives by one-pot multicomponent reaction of isatins, 1,3-diketones, and malononitrile/ ethyl cyanoacetate. Good functional group tolerance and broad scope of usable substrates are other prominent features of the present methodology.
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Michael addition reactions of triketopiperazine (TKP) derivatives to enones, mediated by a cinchona alkaloid-derived catalyst, deliver products in high yield and enantiomeric ratio (er). Use of unsaturated ester, nitrile or sulfone partners gives bridged hydroxy-diketopiperazine (DKP) products resulting from a novel Michael addition-ring closure.
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ژورنال
عنوان ژورنال: Synthetic Communications
سال: 2019
ISSN: 0039-7911,1532-2432
DOI: 10.1080/00397911.2019.1651866