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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]

An enantioselective [3+2] cycloaddition of donor‐acceptor aziridines with N‐aryl protected imines was developed with a Ni(ClO4)2 ⋅ 6H2O/N,N′‐dioxide catalyst system, providing a broad range of chiral trans‐substituted imidazolidine compounds with good yields and excellent enantioselectivities (up to 99 % yield, up to 98 % ee). Control experiments indicated that the products could offer excellent diastereoselectivities with the control of chiral Ni(II)‐N,N′‐dioxide complex and the interaction of the substrates. The possible catalytic process was proposed to rationalize the stereocontrol. [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]

A new 1,3-dipolar cycloaddition of nitrile imines with 3-alkenyl-oxindoles was catalyzed by a new chiral Mg(ClO4)2complex of an N,N′-dioxide ligand. The reaction is so far the sole catalytic synthesis of spiro-pyrazoline-oxindole derivatives. A wide variety of substrates were explored to obtain good yields (up to 98%) and excellent enantioselectivities (up to 99%). This cycloaddition expands the scope of propargyl anion type 1,3-dipole in the construction of 2-pyrazoline subunit. [ABSTRACT FROM AUTHOR]

Abstract: A new self-assembled catalyst based on titanium complex has been developed for the effective enantioselective cyano-ethoxycarbonylation of aldehydes. The self-assembled catalyst was readily prepared from (R)-3,3′-bis((methyl((S)-1-phenylethyl)amino)methyl)-1,1′-binaphthyl-2,2′-diol (1h), N-((1S,2R)-2-hydroxy-1,2-diphenylethyl)acetamide (2b), and tetraisopropyl titanate (Ti(OiPr)4). A variety of aromatic aldehydes, aliphatic aldehydes, and α,β-unsaturated aldehydes were found to be suitable substrates in the presence of the self-assembled titanium catalyst (5mol% 1h, 5mol% 2b, and 5mol% Ti(OiPr)4). The desired cyanohydrin ethyl carbonates were afforded with high isolated yields (up to 95%) and moderate to good enantioselectivities (up to 92% ee) under mild conditions (at −15°C). A possible catalytic cycle based on the experimental observation was proposed. [Copyright &y& Elsevier]

The first iron(iii)/N,N′-dioxide-catalyzed asymmetric haloamination of 3-alkylidene- and 3-arylidene-indolin-2-ones was developed, affording the corresponding chiral oxindole derivatives bearing vicinal haloamine substituents with excellent results (up to 99% yield, 99% ee, ＞19 : 1 dr). This iron catalyst also exhibits perfect enantioselectivity for chalcone derivatives. The cooperative activation of the substrate and the reagent in concert guarantees the high stereoselectivity. [ABSTRACT FROM AUTHOR]

A cooperative bimetallic catalyst system was applied in the catalytic asymmetric cross-dehydrogenative coupling of β-ketoesters and xanthene. Various optically active xanthene derivatives bearing a quaternary stereogenic carbon center were obtained in moderate to good yields (up to 90%) with excellent enantioselectivities (up to 99% ee). Meanwhile, a transition-state model was proposed to explain the origin of the asymmetric induction. [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.

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]

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]

A simple and efficient acylative kinetic resolution of racemic mandelic acid esters is accomplished with a chiral N,N-dioxide-scandium(III) complex under mild and base-free reaction conditions. [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.

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]

A highly efficient enantioselective dicarbofunctionalization reaction of (E)-alkenyloxindoles with pyridinium salts was realized. The process includes the chiral N,N′-dioxide–Sc(III) complex-catalyzed regio-, diastereo-, and enantioselective [3+2] cycloaddition reaction and the following photo-promoted aza-Norrish II type rearrangement. A series of 2-pyridyl substituted oxindole derivatives were obtained in good yields with moderate to good diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of α‐aminoketone derivatives were readily available through a tandem insertion–[1,3] O‐to‐C rearrangement reaction. The rhodium salt and chiral N,N′‐dioxide‐indium(III) complex make up relay catalysis, which enables the O−H insertion of benzylic alcohols to N‐sulfonyl‐1,2,3‐triazoles, and asymmetric [1,3]‐rearrangement of amino enol ether intermediates, subsequently. Preliminary mechanistic studies suggested that the [1,3] O‐to‐C rearrangement step proceeded through an ion pair pathway. [ABSTRACT FROM AUTHOR]

An enantioselective synthesis of α‐aminoketone derivatives were readily available through a tandem insertion–[1,3] O‐to‐C rearrangement reaction. The rhodium salt and chiral N,N′‐dioxide‐indium(III) complex make up relay catalysis, which enables the O−H insertion of benzylic alcohols to N‐sulfonyl‐1,2,3‐triazoles, and asymmetric [1,3]‐rearrangement of amino enol ether intermediates, subsequently. Preliminary mechanistic studies suggested that the [1,3] O‐to‐C rearrangement step proceeded through an ion pair pathway. [ABSTRACT FROM AUTHOR]

An asymmetric one-pot hydrocyanation/Michael reaction of α-aryl diazoacetates with trimethylsilyl cyanide, tert-butanol, and N-phenylmaleimides has been realized. Using a chiral guanidinium salt/CuBr catalyst, a series of cyanide-containing pyrrolidine-2,5-diones could be obtained in good yields with excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

A highly enantioselective formal conjugate allyl addition of allylboronic acids to β,γ‐unsaturated α‐ketoesters has been realized by employing a chiral NiII/N,N′‐dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy‐Cope rearrangement sequence, providing a facile and rapid route to γ‐allyl‐α‐ketoesters with moderate to good yields (65–92 %) and excellent ee values (90–99 % ee). The isolation of 1,2‐allylboration products provided insight into the mechanism of the subsequent oxy‐Cope rearrangement reaction: substrate‐induced chiral transfer and a chiral Lewis acid accelerated process. Based on the experimental investigations and DFT calculations, a rare boatlike transition‐state model is proposed as the origin of high chirality transfer during the oxy‐Cope rearrangement. [ABSTRACT FROM AUTHOR]

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]

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]

A chiral N,N′-dioxide/Ni(OTf)2 complex-catalyzed asymmetric Diels–Alder reaction of cyclopentadiene with 2,3-dioxopyrrolidines and 2-alkenoyl pyridines has been achieved. The corresponding chiral bridged compounds were obtained in high yields with excellent dr and ee values (up to 97% yield, 95 : 5 dr and 97% ee). [ABSTRACT FROM AUTHOR]

The highly enantioselective alkynylation of isatins, catalyzed by a bifunctional guanidine/CuI catalyst under mild reaction conditions, is described. The reaction is broad in scope with respect to alkyl/aryl-substituted terminal alkynes and substituted isatins, thus affording bioactive propargylic alcohols in excellent yields and enantioselectivities. [ABSTRACT FROM AUTHOR]

A highly efficient N, N′-dioxide-NiII catalyst system for the catalytic [3+2] cycloaddition of indoles with epoxides through CC cleavage of oxiranes was accomplished under mild conditions. It provided a promising approach for chiral furo[3,4- b]indoles in up to 98 % yield with up to 91 % enantiomeric excess ( ee) and >95:5 diastereomeric ratio (d.r.). [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]

Abstract: A new bifunctional chiral Al(III) complex of BINOL derivative, which contained tert-amine at 3,3′-position of the BINOL, has been developed for the effective enantioselective hydrophosphonylation of aldehydes. A variety of aromatic, heteroaromatic, condensed-ring, α,β-unsaturated, and aliphatic aldehydes were found to be suitable substrates for the reaction, and the desired α-hydroxy phosphonate were obtained in good to excellent yields (up to 99%) with moderate to good enantioselectivities (up to 87% ee) under mild conditions (at 0°C). A possible catalytic cycle based on the experimental results was proposed. [Copyright &y& Elsevier]

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]

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

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]

An abstract of the article "Synthesis of Chiral Tetrahydrofurans via Catalytic Asymmetric [3 + 2] Cycloaddition of Heterosubstituted Alkenes with Oxiranes" by Xiao Yuan and colleagues is presented.

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.