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The title reaction with isatin-derived ketimines opens the access to various functionalized polycyclic N-heterocycles which include a spirooxindolone unit. In the case of reactant (II) bearing an ethyl ester at the imine function, deprotection takes place. Exclusion of moisture or air is not necessary in the process. The utility of the protocol is demonstrated by preparation of the enantiomerically pure title agent (XIV). [ABSTRACT FROM AUTHOR]

The protocol allows for the preparation of a broad range of cis-1,3-oxazolidines in high yields and with high enantiomeric excesses. [ABSTRACT FROM AUTHOR]

The kinetic resolution of racemic propargyl vinyl ethers (I) through an enantioselective Claisen rearrangement affords chiral allenes (II) and enantiopure ethers (S)-(I). [ABSTRACT FROM AUTHOR]

An abstract of the article "The Asymmetric Synthesis of Polycyclic 3-Spirooxindole Alkaloids via the Cascade Reaction of 2-Isocyanoethylindoles" by Xiaohu Zhao, Xiaohua Liu and colleagues is presented.

An environmentally benign air-insensitive asymmetric reaction of (het)aryl and alkyl glyoxals with various alkyl alcohols is developed which provides Cannizzaro products in high yields and with high enantioselectivities. [ABSTRACT FROM AUTHOR]

Asymmetric dearomatization of indoles is achieved by a cascade reaction between isocyanoethylindole and alkylidene malonates catalyzed by a chiral N,N-dioxide/Mg catalyst. [ABSTRACT FROM AUTHOR]

Chemical equations are presented for the article "Chiral Bifunctional Guanidine-Catalyzed Enantioselective Aza-Henry Reaction of Isatin-Derived Ketimines" by B. Fang & others published in a 2015 issue of the journal "Journal of Organic Chemistry."

A chiral N,N′-dioxide complex (DPR) in combination with Sc(OTf)2 as catalytic system allows the intramolecular cyclization of various oxindole derivatives to form spirocyclic products with high diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

The asymmetric ring-opening/cyclization of cyclopropyl ketones with primary amine nucleophiles is catalyzed by a chiral N,N′-dioxide/scandium(III) complex through a kinetic resolution process. [ABSTRACT FROM AUTHOR]

Optimized reaction conditions including chiral ligands (I) are developed for the Michael reactions of amides (II) with nitroolefins and alkynones. [ABSTRACT FROM AUTHOR]

An abstract of the article "Asymmetric N―H Insertion of Secondary and Primary Anilines under the Catalysis of Palladium and Chiral Guanidine Derivatives" by Y. Zhu, X. Liu and colleagues is presented.

All reaction products are isolated with 98% diastereoisomeric excess. [ABSTRACT FROM AUTHOR]

Chiral N,N′-dioxide/Zn(NTf2)2 complexes are demonstrated to be highly effective in the direct asymmetric conjugate addition of arylacetonitriles to alkylidene malonates under mild conditions. [ABSTRACT FROM AUTHOR]

The article offers chemical equations from the article "Catalytic Asymmetric Homologation of α-Ketoesters with α-Diazoesters: Synthesis of Succinate Derivatives with Chiral Quaternary Centers" by W. Li and others in a 2013 issue of the journal "Angewandte Chemie International Edition 52."

The article focuses on the research titled "Recent Advances in Enantioselective Synthesis of γ-Substituted Butenolides via the Catalytic Asymmetric Vinylogous Reactions" by Q. Zhang, X. Liu and X. Feng published in the "Current Organic Synthesis" in 2013.

An asymmetric chloroamination of 3-alkylidene- and 3-arylidene-indolin-2-ones (I) is developed affording the corresponding chiral oxindole derivatives (III) bearing vicinal anti-chloroamine substituents. [ABSTRACT FROM AUTHOR]

The first example of oxyamination of azlactones with oxaziridines is realized using a chiral bisguanidinium salt with non-coordinating anion. [ABSTRACT FROM AUTHOR]

A chemical diagram is presented that depicts the asymmetric organocatalytic cyclopropanation of cinnamone derivatives with stabilized sulfonium ylides.

A catalytic asymmetric cycloaddition reaction of azaheptafulvenes with alkylidene malonates is developed. [ABSTRACT FROM AUTHOR]

A new catalyst system allows the diastereo- and enantioselective synthesis of various title compounds, precursors of optically active diamines and β-amino acids. [ABSTRACT FROM AUTHOR]

A combination of nickel and iron salts with a chiral proline-derived N,N′-dioxide ligand is an efficient catalytic system for the asymmetric cross-dehydrogenative coupling of cyclic β-ketoesters with xanthene. [ABSTRACT FROM AUTHOR]

Subsequent selective protection group modifications can be accomplished without relevant racemization. [ABSTRACT FROM AUTHOR]

The reaction represents the only catalytic synthesis of spiro-pyrazoline-oxindole derivatives in high yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

This complete OH-selective sequential ene/Prins cyclization towards 4-hydroxy-tetrahydropyrans is characterized by high enantioselectivity, broad substrate scope, facile procedure and mild reaction conditions. [ABSTRACT FROM AUTHOR]

Labeling experiments prove the source of the hydrogen atom to be KBH4. [ABSTRACT FROM AUTHOR]

Investigation of the ligand structures reveals that the presence of sterically demanding substituents such as adamantyl groups is crucial [cf. [ABSTRACT FROM AUTHOR]

The title reaction becomes possible in the presence of Cu(I) agents and chiral cationic guanidinium salts. [ABSTRACT FROM AUTHOR]

The enantioselectivity of the alkylation products can be inverted by simply changing the substitution pattern at the aryl group of the chiral ligands. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric halomaminocyclization of sulfamates (I) with NBS and the catalyst CTA provides the syn-products (II) in good selectivity. [ABSTRACT FROM AUTHOR]

An abstract of the article "Enantioselective Protonation by Aza-Michael Reaction Between Pyrazoles and α-Substituted Vinyl Ketones" by J. Zhang and colleagues is presented.

The asymmetric aldol cyclization of both β,γ-unsaturated α-keto esters and α-keto esters by using Y(OTf)3 and chiral bis(oxazoline) N,N′-dioxide as catalyst is developed. [ABSTRACT FROM AUTHOR]

Optimized conditions render possible the preparation of various pyrazolidinone derivatives as important substructures. [ABSTRACT FROM AUTHOR]

Review: 54 refs + subrefs. [ABSTRACT FROM AUTHOR]

The article presents the asymmetric α-amination of β-keto esters and β-keto amides along with the use of a chiral N,N'-Dioxide—Copper(I) Complex.

A diagram is presented regarding the enantioselective catalysis reaction of isocyanides with alkylidene malonates using A N,N'-Dioxide/Mg(OTf)2 (magnesium triflate) complex catalyst.

The highly diastereoselective and enantioselective title reaction of aryl substituted cyclopropyl ketones with mercaptoacetaldehyde is described. [ABSTRACT FROM AUTHOR]

The scalable procedure provides chiral bridged compounds in high yields and with very high diastereomeric and enantiomeric excesses. [ABSTRACT FROM AUTHOR]

The article presents chemical equation for the article "Bimetallic Gold(I)/Chiral N,N'-Dioxide Nickel(II) Asymmetric Relay Catalysis: Chemo-and Enantioselective Synthesis of Spiroketals and Spiroaminals" by j. Li and others, published in the journal "Angewandte Chemie" in 2016.

The enantioselective alkynylation of isatins catalyzed by a bifunctional guanidine/CuI catalyst under mild reaction conditions is described. [ABSTRACT FROM AUTHOR]

Chiral N,N′-dioxide ligands derived from (S)-pipecolic acid and L-proline in combination with Zn(NTf2)2 are successfully employed as catalyst system for the [2 + 2] cycloaddition of alkynones with cyclic enol ethers to give fused cyclobutenones in good yields and stereoselectivities. [ABSTRACT FROM AUTHOR]

The title reaction affords spirocyclopropane-oxindoles with contiguous tertiary and quaternary centers in high yields with excellent diastereo- and enantioselectivities through a stepwise biradical mechanism. [ABSTRACT FROM AUTHOR]

The conjugate addition of malonic esters to enynes in the presence of a scandium(III)/N,N-dioxide complex yields a range of trisubstituted allenyl ketones with good diastereomeric ratios and excellent e.e.-values. [ABSTRACT FROM AUTHOR]

A chemical reaction is presented for the article "Chiral N,N'-Dioxide-Scandium(III)-Catalyzed Asymmetric Dearomatization of 2-Naphthols Through an Amination Reaction" by X. Lian and colleagues, published in the journal "Chemistry - A European Journal" in 2015.

The design and enantioselective synthesis of cyclopropyl ketones with asymmetric ring form including thoil, alchohol and carboxylic acid based catalysis by Chiral N,N'-Dioxide-Scandium(III) Complex is demonstrated.

An abstract of the study "Asymmetric Synthesis of Furo[3,4-b]indoles by Catalytic [3 + 2] Cycloaddition of Indoles With Epoxides" by W. Chen and colleagues is presented.

An asymmetric 1,3-dipolar cycloaddition of methyleneoxindoles and cyclic azomethine imines affords spirocyclic pyrazolidines in excellent yields and enantioselectivities under mild reaction conditions. [ABSTRACT FROM AUTHOR]

The article presents information on synthesis of optically pure spiro[cyclohexane-oxindoline] derivatives via catalytic asymmetric diels-alder reaction of brassard-type diene with methyleneindolines.

The scalable title reaction of various methyleneindolinones with mono- and 1,1-disubstituted acyclic vinyl ethers, ethylvinyl sulfide (X) and dihydropyran (XII) delivers the corresponding products in high yield, with high to excellent diastereomeric excess and with excellent enantioselectivity. [ABSTRACT FROM AUTHOR]