Search

Herein, an efficient and green procedure for the synthesis of tetrahydro‐β‐carbolines via dehydrogenative coupling of alcohols with tryptamines is reported. The reaction was carried out under mild conditions in the presence of a catalytic amount of the iPrPNP−Mn catalyst and a weak base (Na2CO3). This method tolerated a variety of benzylic and aliphatic alcohol substrates with different functional groups and afforded diverse products in good to excellent isolated yields using tryptamines. Using this strategy, we successfully synthesised pharmaceutical molecules harman, harmaline, and harmine in a concise manner. [ABSTRACT FROM AUTHOR]

Bioethanol is a major raw chemical produced in large quantities by the fermentation of sugar-containing crops and lignocellulosic materials. As a consequence, there is a need for advanced methods to convert ethanol into fine chemicals. Here, we report the synthesis of higher-order alcohols by cross-coupling of ethanol with primary alcohols under solvent-free conditions, catalyzed by low amounts of a selective manganese pincer complex under mild reaction conditions with a stoichiometric amount of sodium ethoxide. Poisoning experiments suggest that the catalysis system is homogeneous. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of an efficient and sustainable synthetic route for formaldehyde production from renewable feedstock, especially in combination with a subsequent transformation to straightforwardly construct valuable chemicals, is highly desirable. Herein, we report a novel manganese‐catalyzed dehydrogenative cyclization of methanol as a formaldehyde surrogate with a variety of dinucleophiles for facile synthesis of N‐heterocycles. The in situ generated formaldehyde via catalytic methanol dehydrogenation can be selectively trapped by diverse dinucleophiles to avoid several possible side reactions. The utility of this transformation is further highlighted by its successful application to the synthesis of 13C‐labeled N‐heterocycles using 13CH3OH as a readily accessible 13C‐isotope reagent. [ABSTRACT FROM AUTHOR]

Glycosylation is critical for monoclonal antibody production because of its impact on pharmacokinetics and pharmacodynamics. Modulation of glycan profile is frequently needed in biosimilar development. However, glycosylation profile is not a single value like that of cell culture titer, hence making it challenging for the Design of Experiment (DoE) methodology to be directly applied. In this study, a Her2-binding antibody was developed as a biosimilar to Herceptin. Cluster analysis was introduced to demonstrate the similarity of glycan profiles between the samples and the reference with specific value—distance. The glycosylation was subsequently optimized with the DoE method. Basal medium and feed medium were found to be the significant factors to the glycosylation pattern. Moreover, a combination of medium and feed strategy was developed to attain the most similar glycoprotein molecule to that of the originator biologic drug. This study may provide an additional option to evaluate multivariable factors and assess biosimilarity and/or comparability in monoclonal antibody production. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Catalytic hydrogenation of esters is essential for the sustainable production of alcohols in organic synthesis and chemical industry. Herein, we describe the first non‐noble metal catalytic system that enables an efficient hydrogenation of non‐activated esters to alcohols in the absence of phosphine ligands (with a maximum turnover number of 2391). The general applicability of this protocol was demonstrated by the high‐yielding hydrogenation of 39 ester substrates including aromatic/aliphatic esters, lactones, polyesters and various pharmaceutical molecules. [ABSTRACT FROM AUTHOR]

Reported herein is a general and efficient dual‐deoxygenative coupling of primary alcohols with 2‐arylethanols catalyzed by a well‐defined Mn/PNP pincer complex. This reaction is the first example of the catalytic dual‐deoxygenation of alcohols using a non‐noble‐metal catalyst. Both deoxygenative homocoupling of 2‐arylethanols (17 examples) and their deoxygenative cross‐coupling with other primary alcohols (20 examples) proceeded smoothly to form the corresponding alkenes by a dehydrogenation and deformylation reaction sequence. "Mn" of action: A general and efficient dual‐deoxygenative coupling of primary alcohols with 2‐arylethanols, catalyzed by a well‐defined manganese/PNP pincer complex, is reported. Mechanistic studies indicate that this transformation undergoes a reaction process involving catalytic dehydrogenation, aldol condensation, and base‐promoted deformylation. [ABSTRACT FROM AUTHOR]

Reported herein is a general and efficient dual‐deoxygenative coupling of primary alcohols with 2‐arylethanols catalyzed by a well‐defined Mn/PNP pincer complex. This reaction is the first example of the catalytic dual‐deoxygenation of alcohols using a non‐noble‐metal catalyst. Both deoxygenative homocoupling of 2‐arylethanols (17 examples) and their deoxygenative cross‐coupling with other primary alcohols (20 examples) proceeded smoothly to form the corresponding alkenes by a dehydrogenation and deformylation reaction sequence. [ABSTRACT FROM AUTHOR]

The effect of temperature gradient on space charge behavior is necessary to investigate for HVDC insulation. In this paper, space charge distributions in neat epoxy resin (EP) and EP/SiO2 nanocomposites (NC) were measured under different DC stresses and temperature gradients. We found that different temperature conditions applied to the electrodes had a great impact on space charge distributions: Only homocharge accumulated near anode at isothermal conditions, on the contrast, at temperature gradient of 60 °C, negative charge injected from cathode (high temperature side) and accumulated in the bulk, heterocharge appeared near anode (low temperature side). Moreover, SiO2 nano-fillers added to NC could suppress the space charge accumulation significantly, and the pattern of space charge distribution in NC at temperature gradient of 60 °C also shows differently from that of EP. Numerical simulation based on the bipolar charge transport model was employed to study the experimental results. It shows that under temperature gradient, charge extraction plays an important role in heterocharge accumulation near the low temperature side. Moreover, it indicates that unlike the apparently measured conductivity, the charge mobility of NC does not increase rapidly with temperature in the range from 20 °C to 80 °C. [ABSTRACT FROM PUBLISHER]

Herein, we describe a selective cobalt-catalyzed chemodivergent transfer hydrogenation of nitriles to synthesize primary, secondary, and tertiary amines. The solvent effect plays a key role for the selectivity control. The general applicability of this procedure was highlighted by the synthesis of more than 70 amine products bearing various functional groups in high chemoselectivity. Moreover, this mild system achieved >2000 TONs (turnover numbers) for the transfer hydrogenation of nitriles. [ABSTRACT FROM AUTHOR]

Herein, we describe a selective cobalt-catalyzed chemodivergent transfer hydrogenation of nitriles to synthesize primary, secondary, and tertiary amines. The solvent effect plays a key role for the selectivity control. The general applicability of this procedure was highlighted by the synthesis of more than 70 amine products bearing various functional groups in high chemoselectivity. Moreover, this mild system achieved >2000 TONs (turnover numbers) for the transfer hydrogenation of nitriles. [ABSTRACT FROM AUTHOR]

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]

Abstract: Starting from peptidomimetic BACE-1 inhibitors, the P2 amino acid including the P2/P3 peptide bond was replaced by a rigid 3-aminomethyl cyclohexane carboxylic acid. Co-crystallization revealed an unexpected binding mode with the P3/P4 amide bond placed into the S3 pocket resulting in a new hydrogen bond interaction pattern. Further optimization based on this structure resulted in highly potent BACE-1 inhibitors with selectivity over BACE-2 and cathepsin D. [Copyright &y& Elsevier]

Abstract: The first catalytic asymmetric three-component reaction of ethyl glyoxylate, para-anisidine, and aliphatic, aromatic alkynes catalyzed by CuOTf·0.5C6H6/pybox 7 has been developed. The protocol provided the corresponding chiral β,γ-alkynyl α-amino acid derivatives in good yields and 66–74% ee. [Copyright &y& Elsevier]

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

This study reports an efficient and green one‐step method for synthesizing thiophene‐substituted ketones from 2‐thiophenemethanol and ketones via dehydrogenative coupling using manganese complexes as catalysts. The manganese complex demonstrated a broad applicability under mild conditions and extended the range of usable substrates. Utilizing this strategy, we carried out an efficient and diverse reaction of ketones with 2‐thiophenemethanol, and successfully synthesized a series of thiophene‐substituted saturated ketones and α, β‐unsaturated ketones in good isolated yields. [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]

In this paper, CexSn1−xOy–F (x = 1, 0.75, 0.5, 0.25, 0) and CexSn1−xOy–A were prepared through a typical reverse co-precipitation method. The experimental results showed that Sn doping could improve the activity and thermal stability of CeO2 in different modes. Comparing the activity and characterization of CexSn1−xOy–F and CexSn1−xOy–A, the improvement of catalyst activity was attributed to the Ce–O–Sn structure with more oxygen vacancies formed by Sn doping, whereas the enhancement of thermal stability was related to the Sn2+ remaining in the CeO2 lattice after accelerated aging. Therefore, a mechanism was proposed that Ce4+–O–Sn2+ is more stable than Ce4+–O–Sn4+ in CexSn1−xOy solid solution. [ABSTRACT FROM AUTHOR]

Review: ca. 200 refs. [ABSTRACT FROM AUTHOR]

The catalytic dehydrogenation of alcohols is essential for the sustainable production of valuable products. This provides a new strategy for green organic synthesis in chemical industries. Herein, we describe a manganese‐based catalytic system that enables the efficient synthesis of C3‐alkylated indoles from benzyl alcohols and indoles via the borrowing hydrogen process. Furthermore, dehydrogenative coupling of 2‐arylethanols and indoles yields C3‐alkenylated indoles. Meanwhile, reacting 2‐aminophenethanol instead of indoles can also obtain the corresponding indole products with high selectivity under the same conditions. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: A Pd‐catalyzed asymmetric aromative [4+3]‐cyclization reaction of amino‐trimethylenemethanes (TMM, 1,3‐dipoles) with fused 1‐azadienes has been developed. This method enables access to the synthetically importance and biologically active benzofuran fused azepines and indeno‐azepines in excellent efficiency and stereoselectivity (up to 95% yield, 99% ee, >19 : 1 dr). [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 Pd‐catalyzed asymmetric allenylic [4+1] cycloaddition was successfully developed. Alternatively, tuning the Pd catalyst switched the reactivity toward an unprecedented [4+3] cycloaddition/cross‐coupling. Ligands play a vital role in controlling the reaction pathway, allowing highly selective access to different products from identical substrates. Biological evaluation of the obtained compounds led to the discovery of new antitumor targets. A possible mechanism is proposed, suggesting two interesting catalytic cycles for the cycloaddition with palladium‐butadienyls. This study also demonstrated the potential and utility of allenic esters as 1,4‐biselectrophiles and C4 synthons for participating in cycloaddition reactions. Switch it: The use of metal‐butadienyl species in a cycloaddition is exemplified by the first Pd‐catalyzed asymmetric allenylic [4+1] cycloaddition. Notably, tuning the Pd catalysts switched the reactivity toward an unprecedented [4+3] cycloaddition/cross‐coupling. These reactions lead to diverse and valuable carbocycles and heterocycles, and also provide a straightforward synthesis to [3]dendralenes. [ABSTRACT FROM AUTHOR]

The first Pd‐catalyzed asymmetric allenylic [4+1] cycloaddition was successfully developed. Alternatively, tuning the Pd catalyst switched the reactivity toward an unprecedented [4+3] cycloaddition/cross‐coupling. Ligands play a vital role in controlling the reaction pathway, allowing highly selective access to different products from identical substrates. Biological evaluation of the obtained compounds led to the discovery of new antitumor targets. A possible mechanism is proposed, suggesting two interesting catalytic cycles for the cycloaddition with palladium‐butadienyls. This study also demonstrated the potential and utility of allenic esters as 1,4‐biselectrophiles and C4 synthons for participating in cycloaddition reactions. [ABSTRACT FROM AUTHOR]

The application potential of primary amine catalysts in the context of Mannich reactions of aldehydes with ketimines is exemplified by isatin-derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide useful methods for the syntheses of chiral 3-substituted 3-amino-2-oxindoles and dihydroquinazolinones bearing a trifluoromethylated quaternary stereocenter. The synthetic utility of the reactions is demonstrated through the formal synthesis of AG-041R and DPC 083 and the total synthesis of (−)-psychotriasine. [ABSTRACT FROM AUTHOR]

The application potential of primary amine catalysts in the context of Mannich reactions of aldehydes with ketimines is exemplified by isatin-derived ketimines and cyclic trifluoromethyl ketimines. Primary amine catalysts exhibit either unusual stereoselectivity or reactivity, which is not observable with secondary amine catalysts. Moreover, reversal of diastereofacial selectivity between primary and secondary amine catalysts is disclosed. These new reactions provide useful methods for the syntheses of chiral 3-substituted 3-amino-2-oxindoles and dihydroquinazolinones bearing a trifluoromethylated quaternary stereocenter. The synthetic utility of the reactions is demonstrated through the formal synthesis of AG-041R and DPC 083 and the total synthesis of (−)-psychotriasine. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ag-supported CoCe porous nanosheet exhibited ultra-low ignition temperature. • Ag+ species derived from the Ag-Co interface effectively regulated the valence state of Co ions. • In-situ TEM confirmed the key role of Ag species for the ultra-low ignition temperature. • DFT calculations proved the synergistic effect and role of interface between Ag and Co. As a major technology, catalytic combustion is now widely used in reducing harmful soot emissions from diesel combustion. However, large amounts of soot are still emitted to atmosphere due to the lower exhaust temperature (below 200 °C) of diesel engines caused by frequent idling and cold start. Therefore, more and continued efforts are still needed to reduce the ignition temperature of T 10 (at which 10 % of soot is converted) in terms of energy efficiency and environmental sustainability. In this work, an Ag-supported CoCe porous nanosheets catalyst was developed, through which a T 10 < 230 °C was achieved under loose contact mode without the assistance of other atmosphere such as NO x. The detailed characterization of catalysts indicated that the motionless and mobile Ag particles, together with the regulation of valence state of Co ions by the abundant Ag+ species derived from Ag-Co interface are responsible for the ultra-low soot ignition temperature. Density functional theory (DFT) calculations proved that the electronic structure of Co can be tuned by the interactions between Ag and the support, which would promote the adsorption of O 2. More importantly, the synergistic effect between Ag and Co, along with the formed interface can lower the dissociation energy barrier of O 2 , thus achieving a process with fast kinetics. In summary, the appropriate design of catalysts for soot combustion needs to consider both intrinsic activity and morphology, so that a significant reduction of soot emissions from vehicle exhaust can be achieved at low temperature. [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]

The first arylation strategy for the synthesis of enantioenriched propargylamines is disclosed. This approach, which is complementary to previous alkynylation and alkylation strategies, involves a C(sp2)−C(sp3) bond formation, and is based on the first asymmetric Friedel-Crafts-type arylation reaction of C-alkynyl imines. Asymmetric Friedel-Crafts reactions with electron-deficient phenols, a longstanding unsolved challenge, have thus been realized for the first time, enabled by the combination of our recently introduced C-alkynyl N-Boc-protected N,O-acetals as electrophiles and chiral phosphoric acids as catalysts. The synthetic utility of the resulting structurally diverse and polyfunctional chiral propargylamines was demonstrated by a series of selective transformations, including controlled reduction of the alkynyl group and iterative cross-couplings. [ABSTRACT FROM AUTHOR]

The first arylation strategy for the synthesis of enantioenriched propargylamines is disclosed. This approach, which is complementary to previous alkynylation and alkylation strategies, involves a C(sp2)−C(sp3) bond formation, and is based on the first asymmetric Friedel-Crafts-type arylation reaction of C-alkynyl imines. Asymmetric Friedel-Crafts reactions with electron-deficient phenols, a longstanding unsolved challenge, have thus been realized for the first time, enabled by the combination of our recently introduced C-alkynyl N-Boc-protected N,O-acetals as electrophiles and chiral phosphoric acids as catalysts. The synthetic utility of the resulting structurally diverse and polyfunctional chiral propargylamines was demonstrated by a series of selective transformations, including controlled reduction of the alkynyl group and iterative cross-couplings. [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]

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 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]

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]

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.

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.

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