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The first example of chiral secondary amine and iridium(i) co-catalyzed enantioselective three-component reaction of aryldiazoacetates, indoles and enals was rationally designed and developed to afford 3-substituted indole derivatives in good yields and with moderate diastereoselectivity as well as excellent enantioselectivity. This reaction is proposed to proceed through the enantioselective trapping of iridium(i)-associated zwitterionic intermediates via selective 1,4-addtition to the chiral amine activated enals. [ABSTRACT FROM AUTHOR]

The chiral RhI-diene-catalyzed asymmetric three-component reaction of aryldiazoacetates, aromatic amines, and β-nitroacrylates was achieved to obtain γ-nitro-α-amino-succinates in good yields and with high diastereo- and enantioselectivity. This reaction is proposed to proceed through the enantioselective trapping of RhI-associated ammonium ylides by nitroacrylates. This new transformation represents the first example of RhI-carbene-induced ylide transformation. [ABSTRACT FROM AUTHOR]

An elegant synergistic catalytic system comprising a ruthenium complex with a chiral Brønsted acid was developed for a four-component Mannich/cascade aza-Michael reaction. The ruthenium-associated ammonium ylides successfully trapped with in situ generated imines indicates a stepwise process of proton transfer in the ruthenium-catalyzed carbenoid NH insertion reaction. The different decomposition abilities of various ruthenium complexes towards diazo compounds were well explained by the calculated thermodynamic data. The transformation features a mild, rapid, and efficient method for the synthesis of enantiomerically pure 1,3,4-tetrasubstituted tetrahydroquinolines bearing a quaternary stereogenic carbon center from simple starting precursors in moderate yields with high diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

A highly enantioselective trapping of protic phosphoramidate ammonium ylides with α-imino esters is reported. The intriguing Rh2(OAc)4 and chiral Brønsted acid co-catalyzed three-component Mannich-type reaction of a diazo compound, a phosphoramidate, and an α-imino ester provides a rapid and efficient access to 2,3-diaminosuccinic acid derivatives with a high level control of diastereo- and enantioselectivity. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "A Transformation of Cyclopropyl Carbene: A Highly Enantioselective Three-Component Reaction via Trapping Oxonium Ylide by Imine" by Mingfeng Li and others, published in the journal "Tetrahedron" in 2016.

The first example of chiral secondary amine and iridium(I) co-catalyzed enantioselective three-component reaction of aryldiazoacetates, indoles and enals is developed to afford 3-substituted indole derivatives in good yields and with moderate diastereoselectivity as well as excellent enantioselectivity. [ABSTRACT FROM AUTHOR]

An abstract of the article "An Ylide Transformation of Rhodium(I) Carbene: Enantioselective Three-Component Reaction Through Trapping of Rhodium(I)-Associated Ammonium Ylides by Β-Nitroacrylates" by Xiaochu Ma and colleagues is presented.

A four-component Mannich/cascade aza-Michael reaction using a ruthenium complex with a chiral Broensted acid is developed. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Efficient Synthesis of Chiral Cyclic Acetals by Metal and Broensted Acid Co-Catalyzed Enantioselective Four-Component Cascade Reactions" by X. Guo and others published in the journal "Chemical Communications" in the 2014 issue.