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Structurally diverse 3,3′-thiopyrrolidonyl spirooxindoles bearing three contiguous stereogenic centers can be smoothly prepared via domino Michael/cyclization reaction using quinine as chiral catalyst. [ABSTRACT FROM AUTHOR]

Attractive features of this protocol are the utilization of readily available substrates, reagents, and catalysts, as well as simplicity and mild conditions. [ABSTRACT FROM AUTHOR]

In the presence of the newly designed thiourea-binol catalyst, a broad range of alkylaminophenols is obtained in good yield and good to high enantioselectivity (up to 95% e.e.). [ABSTRACT FROM AUTHOR]

A diagram is presented which explains the chemical process of organocatalytic asymmetric Michael addition of 3-Pyrrolyloxindoles to β-Phthalimidonitroethene for the synthesis of 3,3′-Disubstituted Oxindoles bearing contiguous 3,α,β-Triamino functionality.

The products are formed with excellent diastereo and enantioselectivities. [ABSTRACT FROM AUTHOR]

Chemical equation related to Asymmetric Michael Reaction of Arylacetyl Phosphonates to Nitroalkenes with Bifunctional Amine-Thiourea Catalyst Bearing Multiple-Hydrogen-Bond Donor by M.L. Zhang and colleagues published in the "Tetrahedron" periodical is presented.

An abstract of the article "Organocatalytic Asymmetric Henry Reaction of 1H-Pyrrole-2,3-diones with Bifunctional Amine-Thiourea Catalysts Bearing Multiple Hydrogen-Bond Donors" by K. Kobayashi and colleagues is presented.

An abstract of the article "Organocatalytic Asymmetric Michael/Cyclization Cascade Reactions of 3-Hydroxyoxindoles/3-Aminooxindoles with α,β-Unsaturated Acyl Phosphonates for the Construction of Spirocylic Oxindole-γ-lactones/lactams" by Chen L and colleagues is presented.

The method proves superior to previously developed protocols, thus providing variously substituted polycyclic spirooxindoles in virtually quantitative yields with excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

The reaction tolerates aryl, but no alkyl substituted butenolides and aryl, hetaryl, alkyl, and carboxyl-substituted 2-enoylpyridines. [ABSTRACT FROM AUTHOR]

An abstract of the article "Enantioselective Synthesis of 3,3-Disubstituted Oxindoles Bearing Two Different Heteroatoms at the C3 Position by Organocatalyzed Sulfenylation and Selenenylation of 3-Pyrrolyl-oxindoles" by Y. You and colleagues is presented.

The scalable and efficient method provides various polycyclic spirooxindoles with three contiguous chiral centers, two of which are quarternary, in excellent yields and with high to excellent dia- and enantioselectivities. [ABSTRACT FROM AUTHOR]

A broad range of complex 3,3′-disubstituted oxindoles bearing two stereogenic centers are obtained in high yields and with high to excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

Spirocyclic oxindoles are obtained by the title cyclization reaction with good to excellent diastereo- and enantioselectivities. [ABSTRACT FROM AUTHOR]

A squaramide-substituted cinchona alkaloid is successfully applied as catalyst for the synthesis of chiral oxindoles such as (III) and (V) by Michael addition of 3-pyrrolyloxindoles with nitroalkenes. [ABSTRACT FROM AUTHOR]

Crucial for the enantiomeric excess is the presence of an ortho-substituent on one of the two aromatic rings. [ABSTRACT FROM AUTHOR]

The absolute configuration of the products is not determined. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to article "Organocatalytic Asymmetric Double Michael Reaction of Nazarov Reagents with Alkylidene Azlactones for the Construction of Spiro-Fused Cyclohexanone/5-Oxazolone System" by J. Zuo and others, published in periodical "Tetrahedron" in 2014.

An abstract of the article "Quinine-Catalyzed Asymmetric Domino Michael-Cyclization Reaction for the Synthesis of Spirocyclic Oxindoles Bearing Two Spiro Quaternary Centers and Three Consecutive Stereocenters," by Bao-Dong Cui and colleagues is presented.

Chemical equations for article "Asymmetric Synthesis of β-Hydroxy-α-amino Phosphonic Acid Derivatives via Organocatalytic Direct Aldol Reaction of &#945-Isothiocyanato Phosphonates with Aldehydes" by W.Y. Han, and others, published in "Journal of Organic Chemistry" in 2013 are presented.

This method yields 3-aminooxindoles with adjacent quaternary and tertiary stereocenters in good yields and with good diastereo- and enantioselectivities under mild reaction conditions. [ABSTRACT FROM AUTHOR]

A novel L-serine derived catalyst is investigated for the stereoselective hydrosilylation of α-acetamido-β-enamino esters. [ABSTRACT FROM AUTHOR]

The preparation of thiols (III) proceeds with reasonable diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

Optimized conditions including optically active thioureas allow the synthesis of the title compounds in very short reaction times. [ABSTRACT FROM AUTHOR]

The article presents the steps of the chemical equations involved in a cascade michael/cyclization process with amino-thiocarbamate catalysts.

An abstract related to the synthesis of a series of novel chiral Lewis base catalysts is presented.

The reaction can also be carried out with some other Lewis acids, but a catalyst loading <10% gives only rise to trace amounts. [ABSTRACT FROM AUTHOR]

The asymmetric reduction of benzoxazines with trichlorosilane gives the corresponding products (II) with mostly moderate enantioselectivity. [ABSTRACT FROM AUTHOR]

The domino-Michael-type Friedel-Crafts alkylation/cyclization of β-naphthol (and its 6-bromo derivative) with arylidene Meldrum′s acid derivatives is catalyzed by a bifunctional thiourea catalyst to give the title compounds in high yield but only moderate enantioselectivities. [ABSTRACT FROM AUTHOR]