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A highly enantioselective catalytic protocol for the desymmetrization of meso-aziridines via ring-opening with pyrazoles is reported using an N,N′-dioxide-Mg(OTf)2 complex as the catalyst. The corresponding trans-α-pyrazole-substituted amines were obtained in good yields and enantioselectivities (up to 99% yield and 94% ee) under mild reaction conditions. Moreover, a remarkably high asymmetric amplification was observed in the catalytic system. [ABSTRACT FROM AUTHOR]

A highly efficient asymmetric dearomatization of indoles was realized through a cascade reaction between 2-isocyanoethylindole and alkylidene malonates catalyzed by a chiral N,N′-dioxide/MgII catalyst. Fused polycyclic indolines containing three stereocenters were afforded in good yields with excellent diastereo- and enantioselectivities through a Michael/Friedel-Crafts/Mannich cascade. When 2-substituted 2-isocyanoethylindoles were used, spiroindoline derivatives were obtained through a Michael/Friedel-Crafts reaction. [ABSTRACT FROM AUTHOR]

Unter milden Bedingungen und in Gegenwart des Katalysators L/Y(OTf)3 gelang erstmals die Titelreaktion. Über eine 1,2 ‐ Aryl ‐ oder 1,2 ‐ Alkyl ‐ Verschiebung wurden hoch funktionalisierte Succinat ‐ Derivate mit einem quartären Stereozentrum mit ausgezeichneten Ausbeuten und Enantioselektivitäten erhalten. Tf=Trifluormethansulfonyl. [ABSTRACT FROM AUTHOR]

The catalytic asymmetric aza-Michael reaction of benzoyl hydrazine toward chalcones through the nonactivated amine moiety conjugated addition was facilitated by the developed N,N′-dioxide-Sc(OTf)3complex under mild conditions, affording the pharmacologically and synthetically useful products in moderate to high yields with up to 97% ee. [ABSTRACT FROM AUTHOR]

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 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.

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

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 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 process affords 2-acyl substituted norbornadienes in moderate to high yields with good enantiomeric excess up to 95%. [ABSTRACT FROM AUTHOR]

Moreover, the simple α-keto ester (X) can also be converted to the corresponding product (XI). [ABSTRACT FROM AUTHOR]

An abstract of the article "Scandium-Catalyzed Asymmetric 1,6-Addition of 3-Substituted Oxindoles to Linear Dienyl Ketones" by Z. Wang and colleagues is presented.

A diagram is presented which explains the enantioselective synthesis of dihydrocoumarin derivatives.

The title process tolerates a wide range of functional groups and provides dihydropyranones with excellent enantioselectivities. [ABSTRACT FROM AUTHOR]

This is a highly efficient Ni(II)-catalyzed Claisen rearrangement of a variety of both propargyl and allyl vinyl ethers using a chiral N,N-dioxide as ligand. [ABSTRACT FROM AUTHOR]

This new process proceeds under mild conditions, exhibits a broad substrate scope and functional-group tolerance, and features good air and moisture tolerance. [ABSTRACT FROM AUTHOR]

An efficient catalytic system is found for the asymmetric ring-opening of meso-aziridines with different nucleophiles, e.g. aniline, water, and methanol. [ABSTRACT FROM AUTHOR]

The scalable title reaction affords the products with high diastereo- and enantioselectivities under mild conditions. [ABSTRACT FROM AUTHOR]

The scalable method is applicable to a broad range of arylated oxindoles and diaryliodonium salts with high to excellent enantioselectivity. [ABSTRACT FROM AUTHOR]