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An interesting β‐isoquinidine catalyzed divergent reaction was developed to produce either spirocyclopentene oxindoles, spirocyclopentadiene oxindoles or bisoxindoles in a high enantioselective fashion. The utility of this protocol was demonstrated by the versatile transformations of the products. This work not only represents the first highly stereoselective intermolecular catalytic asymmetric allylic alkylation reaction between two isatin‐derived MBH carbonate molecules but also constitutes a rare example of isatin‐derived MBH carbonate‐based enantioselective and α‐regioselective [3+2] cycloaddition reactions. [ABSTRACT FROM AUTHOR]

Abstract: In this communication, we report a substrate‐controlled product diversity in the 1,5,7‐triazabicyclo[4.4.0]dec‐5‐ene (TBD)‐catalyzed cascade cyclization of 2‐alkynyl‐3,3‐difluoro‐3H‐indoles with N,N‐ or N,S‐bis‐nucleophiles. The products represent two important heterocyclic compounds, C2‐spiro indoline, and pyrimido[1,2‐a]benzimidazole, featuring a versatile gem‐difluoromethylene group on the framework. In these cascade processes, two new C−N bonds, or one C−S and one C−N bond, are consecutively formed in a single step. The present protocol is characterized with high regioselectivity, high yield, broad substrate scope, good functional group tolerance, facile scalability and mild reaction conditions. [ABSTRACT FROM AUTHOR]

We report an organocatalytic addition of nitromethane to aryl α-ketoester-derived N-tosyl ketimines or isatin-derived N- tert-butyloxycarbonyl ketimines, catalyzed by 1,8-diazabicyclo[5.4.0]undec-7-ene (1-5 mol %). Initial screenings reveal that the reaction with a quinine-derived bifunctional catalyst, which features a C6 phenolic hydroxy group, achieved up to 71 % ee. [ABSTRACT FROM AUTHOR]

Immer der Reihe nach: Eine organokatalytische Sequenz aus Morita ‐ Baylis ‐ Hillman(MBH) ‐ Reaktion, Bromierung und [3+2] ‐ Ringschluss führt hoch stereoselektiv zu Bis(spirooxindolen) mit benachbarten Spiro ‐ Stereozentren. Der Schlüsselschritt dabei ist der katalytische asymmetrische [3+2] ‐ Ringschluss zwischen von Isatinen abgeleiteten MBH ‐ Addukten, die eine vierfach substituierte Doppelbindung tragen, und weiteren Isatinderivaten. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "One-Pot Tandem Approach to Spirocyclic Oxindoles Featuring Adjacent Spiro-Stereocenters" by Y.-L. Liu and others, published in the periodical "Angewandte Chemie" in 2013.

Chinchona alkaloid derived urea and thiourea derivatives are successfully applied as catalysts in the enantioselective preparation of difluorinated oxindoles such as (III) and (VII). [ABSTRACT FROM AUTHOR]

An abstract of the article "Highly Enantioselective Michael Addition of 3-Arylthio- and 3-Alkylthiooxindoles to Nitroolefins Catalyzed by a Simple Cinchona Alkaloid Derived Phosphoramide" is presented.