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Abstract: An unprecedented effect of the ligand-to-metal ratio on the stereofacial selection in the copper-catalyzed enantioselective addition of terminal alkynes to N-PMP-α-imino esters was observed. An excess of ligand was found not to be beneficial, on the contrary, an excess of copper was found to be beneficial. Moreover, both enantiomers of the alkynylation product were obtained with almost the same enantiomeric excess with the same chiral ligand by simply adjusting the ligand-to-metal ratio. The investigation of the mechanism demonstrated the presence of a positive nonlinear effect [(+)-NLE]. [Copyright &y& Elsevier]

The first organocatalytic synthesis of terminal propargylic amines from aldehydes via tandem amination/Seyferth-�Gilbert alkynylation has been developed. The described protocol provides the formal addition products of acetylene (HC≡CH) to ali�phatic imines, which are not easily obtained directly. [ABSTRACT FROM AUTHOR]

Abstract: A short review on the development and application of chiral primary amine catalysts in organocatalytic enantioselective reactions has been described. [Copyright &y& Elsevier]

A novel catalytic enantioselective synthesis of functionalized 1,3-enynes has been developed featuring the design and synthesis of conjugated nitro dienynes as a useful new class of Michael acceptors. Moreover, a simple, yet flexible catalytic cascade approach to functionalized enantioenriched acyclic α,β-enones and cyclic dienones has also been developed. [ABSTRACT FROM AUTHOR]

Herein we report a Pd‐catalyzed asymmetric allenylic alkylation strategy for the direct functionalization of 1H‐indoles by employing P‐chiral BIBOP‐type ligands. The regioselectivity (N1/C3) of this process can be switched efficiently. Using Cs2CO3 at elevated temperatures in MeCN, N1‐alkylated indoles bearing axial chirality with a stereocenter non‐adjacent (β) to the nitrogen are produced in good yields with high enantioselectivity and complete N1‐regioselectivity regardless of the electronic properties and substitution patterns of diverse indoles. Using K2CO3 at room temperature in CH2Cl2, chiral C3‐alkylated indoles can also be obtained. Notably, we introduce a new class of tri‐substituted allenylic electrophiles that proceeded through different pathways from di‐substituted allenylic electrophiles. [ABSTRACT FROM AUTHOR]

Herein we report a Pd‐catalyzed asymmetric allenylic alkylation strategy for the direct functionalization of 1H‐indoles by employing P‐chiral BIBOP‐type ligands. The regioselectivity (N1/C3) of this process can be switched efficiently. Using Cs2CO3 at elevated temperatures in MeCN, N1‐alkylated indoles bearing axial chirality with a stereocenter non‐adjacent (β) to the nitrogen are produced in good yields with high enantioselectivity and complete N1‐regioselectivity regardless of the electronic properties and substitution patterns of diverse indoles. Using K2CO3 at room temperature in CH2Cl2, chiral C3‐alkylated indoles can also be obtained. Notably, we introduce a new class of tri‐substituted allenylic electrophiles that proceeded through different pathways from di‐substituted allenylic electrophiles. [ABSTRACT FROM AUTHOR]

A method for the asymmetric construction of functionalized acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements has been developed via organo/metal dual catalyzed asymmetric allenylic substitution of branched and linear aldehydes, by developing an unknown acyclic secondary‐secondary diamine as the enabling organocatalyst. Although it is believed that secondary‐secondary diamines are difficult to be used as the organocatalysts in organo/metal dual catalysis, this study demonstrates that such diamines can be successfully combined with a metal catalyst in organo/metal dual catalysis. Our study enables the asymmetric construction of two important classes of motifs which were previously difficult to access, axially chiral allene‐containing acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements bearing allenyl axial chirality and central chirality, in good yields with high enantio‐ and diastereoselectivity. [ABSTRACT FROM AUTHOR]

A method for the asymmetric construction of functionalized acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements has been developed via organo/metal dual catalyzed asymmetric allenylic substitution of branched and linear aldehydes, by developing an unknown acyclic secondary‐secondary diamine as the enabling organocatalyst. Although it is believed that secondary‐secondary diamines are difficult to be used as the organocatalysts in organo/metal dual catalysis, this study demonstrates that such diamines can be successfully combined with a metal catalyst in organo/metal dual catalysis. Our study enables the asymmetric construction of two important classes of motifs which were previously difficult to access, axially chiral allene‐containing acyclic all‐carbon quaternary stereocenters and 1,3‐nonadjacent stereoelements bearing allenyl axial chirality and central chirality, in good yields with high enantio‐ and diastereoselectivity. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to an article on catalytic asymmetric synthesis of 1,3-enyne scaffolds and its design and synthesis of conjugated nitro dienynes by X. Li and others, published in the journal "Chemical Communication" in 2014.

The first metal-catalyzed 1,4-selective asymmetric addition of malonates to nitroenynes promoted by a simple chiral nickel(II)-diamine catalyst, was developed, facilitating a mild synthesis of a novel type of multifunctional chiral β-alkynyl acids bearing a nitro group. Based on this protocol, we have developed a practical and collective synthesis of a series of diverse functional molecules and building blocks including new types of chiral β-alkynyl-γ-amino acids, β-functionalized chiral δ-keto-γ-lactones, chiral γ-alkylidenelactones, alkynyl-substituted pyrrole-3-carboxylic acid derivatives, tetrasubstituted furans and chiral β-alkynyl-γ-lactams. Notably, we discovered two unusual tandem reactions leading to functionalized chiral 1,5-dicarbonyl compounds. In addition, by employing simple bifunctional organocatalysts, we have developed the first regio-, diastereo- and enantioselective conjugate addition of α-substituted β-keto esters to nitroenynes, which is poorly diastereoselective with chiral nickel(II)-diamine catalysts, providing a new entry to adjacent quaternary and tertiary stereocenters in one step. Based on this protocol, we have developed a concise asymmetric synthesis of conformationally constrained bicyclic γ2-amino acids featuring an alkynyl side chain with an adjacent quaternary carbon stereocenter. The study described here demonstrates that the mutually complementary strategy of transition metal catalysis and organocatalysis is a powerful and promising tool in catalytic asymmetric synthesis. [ABSTRACT FROM AUTHOR]

The strong binding ability of P‐ylides with transition metals limits the utilization of stabilized P‐ylide as nucleophiles in asymmetric organometallic catalysis. Herein we describe the first rhodium‐catalyzed asymmetric ring‐opening reaction of P‐ylides utilizing oxabicyclic alkenes as the electrophilic partner. Various P‐ylides including ester‐, ketone‐ and amide‐style P‐ylides are all applicable. This asymmetric reaction occurs through the cleavage of two bridgehead C−O bonds and the formation of two C−C bonds, and oxabenzonorbornadienes are used as 1,4‐biselectrophiles, thus providing access to benzonorcaradienes in good yields with high enantioselectivity and perfect diastereoselectivity. The present protocol also constitutes the first highly enantioselective direct catalytic asymmetric cyclopropanation of stabilized P‐ylide nucleophiles. [ABSTRACT FROM AUTHOR]

The strong binding ability of P‐ylides with transition metals limits the utilization of stabilized P‐ylide as nucleophiles in asymmetric organometallic catalysis. Herein we describe the first rhodium‐catalyzed asymmetric ring‐opening reaction of P‐ylides utilizing oxabicyclic alkenes as the electrophilic partner. Various P‐ylides including ester‐, ketone‐ and amide‐style P‐ylides are all applicable. This asymmetric reaction occurs through the cleavage of two bridgehead C−O bonds and the formation of two C−C bonds, and oxabenzonorbornadienes are used as 1,4‐biselectrophiles, thus providing access to benzonorcaradienes in good yields with high enantioselectivity and perfect diastereoselectivity. The present protocol also constitutes the first highly enantioselective direct catalytic asymmetric cyclopropanation of stabilized P‐ylide nucleophiles. [ABSTRACT FROM AUTHOR]

The first enantioselective conjugate additions of problematic aromatic ketones and acetone to nitrodienynes have been achieved by employing a chiral multifunctional primary amine catalyst recently developed by us. The reactions took place in a 1,4-manner. Furthermore, by utilizing the resulting chiral functionalized 1,3-enynes as a starting point, we have developed unprecedented p-toluenesulfonic acid-catalyzed tandem annulations, which allow the efficient and selective construction of various synthetically useful cyclic 1,5-diketones (R=Ar) and dienones (R=Me). [ABSTRACT FROM AUTHOR]

Thefirst method for the asymmetric synthesis of C3-monosubstitutedchiral carbazolones, structural motifs common in medicinal chemistry,has been achieved using Pd-catalyzed decarboxylative protonation ofcarbazolones. This methodology has been applied to the first catalyticenantioselective formal synthesis of (−)-aspidofractinine withstep economy and simplicity. [ABSTRACT FROM AUTHOR]

We report the first catalytic asymmetric approach to octahydroindolones and a divergent enantioselective synthesis of perhydroindole alkaloids, as exemplified by lycorine-type Amaryllidaceae alkaloids (+)-α-lycorane and (+)-lycorine, from a common intermediate by using a highly concise route. The assembly of octahydroindolones employs a catalytic enantioselective 1,4-conjugate addition of nitro dienynes, followed by a TsOH-catalyzed cascade synthesis of highly functionalized enones, and a diastereoselective intramolecular Michael addition. [ABSTRACT FROM AUTHOR]

This is the first metal-catalyzed 1,4-selective asymmetric addition of malonates to nitroenynes using a nickel(II)-diamine catalyst. [ABSTRACT FROM AUTHOR]

The method is highly enantio- and diastereoselective and affords less accessible 3-aminooxindoles with vicinal tetrasubstituted stereocenters. [ABSTRACT FROM AUTHOR]

The first catalytic enantioselective formal synthesis of (-)-aspidofractinine (II) is achieved via key intermediate (I), which is synthesized in only ten steps from commercially available starting materials. [ABSTRACT FROM AUTHOR]

The article presents a chemical structure of Lycorine-Type Amaryllidaceae Alkaloids (+)-α-Lycorane and (+)-Lycorine.