Recent Advances in Homogeneous Catalysts for the Asymmetric Hydrogenation of Heteroarenes

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(23), P. 13834 - 13851

Published: Nov. 12, 2020

The asymmetric hydrogenation of heteroarenes has recently emerged as an effective strategy for the direct access to enantioenriched, saturated heterocycles. Although several homogeneous catalyst systems have been extensively developed with high levels chemo- and stereoselectivity, development mild conditions that allow efficient stereoselective a broad range substrates remains challenge. This Perspective highlights recent advances in catalysis heteroarene inspiration further catalysts, addresses underdeveloped areas limitations current technology.

Language: Английский

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Recent Strategies in the Nucleophilic Dearomatization of Pyridines, Quinolines, and Isoquinolines

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(3), P. 1122 - 1246

Published: Jan. 2, 2024

Dearomatization reactions have become fundamental chemical transformations in organic synthesis since they allow for the generation of three-dimensional complexity from two-dimensional precursors, bridging arene feedstocks with alicyclic structures. When those processes are applied to pyridines, quinolines, and isoquinolines, partially or fully saturated nitrogen heterocycles formed, which among most significant structural components pharmaceuticals natural products. The inherent challenge lies low reactivity heteroaromatic substrates, makes dearomatization process thermodynamically unfavorable. Usually, connecting event irreversible formation a strong C–C, C–H, C–heteroatom bond compensates energy required disrupt aromaticity. This aromaticity breakup normally results 1,2- 1,4-functionalization heterocycle. Moreover, combination these subsequent tandem stepwise protocols allows multiple heterocycle functionalizations, giving access complex molecular skeletons. aim this review, covers period 2016 2022, is update state art nucleophilic dearomatizations showing extraordinary ability dearomative methodology indicating their limitations future trends.

Language: Английский

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Recent Progress in Transition-Metal-Catalyzed Asymmetric Reductive Amination

ACS Catalysis, Journal Year: 2021, Volume and Issue: 11(22), P. 13809 - 13837

Published: Oct. 29, 2021

Asymmetric reductive amination (ARA) of a prochiral carbonyl compound with an amine using H2/hydrogen surrogate is concise and operationally simple method for the synthesis chiral amines. ARA proceeds via condensation group amine/ammonia followed by enantioselective reduction generated intermediate. The activation reductant stereoselective transfer hydrogen to intermediate imine/enamine often mediated transition metal catalyst. Considering wide applications enantiopure amines in pharmaceuticals, agrochemicals, materials, development effective catalysts has been intensively pursued last two decades. Since first report Blaser 1999, this key research area grown significantly recent years, as reflected advances catalyst design, diversifying substrate scope better mechanistic understanding. Several highly efficient general methodologies applicable challenging partners have demonstrated, providing ready access variety In Review, we present progress featuring diverse employing metal-catalysts. This Review provides organized critical discussion on engineering evolution, expanding susbstrate insights. To conclude, remaining challenges opportunities are also highlighted.

Language: Английский

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Recent advances on transition-metal-catalysed asymmetric reductive amination

Organic Chemistry Frontiers, Journal Year: 2021, Volume and Issue: 8(10), P. 2328 - 2342

Published: Jan. 1, 2021

This review focuses on the recent progress of homogeneous transition-metal-catalysed asymmetric reductive amination ketones with diverse nitrogen sources.

Language: Английский

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A diversity of recently reported methodology for asymmetric imine reduction

Organic Chemistry Frontiers, Journal Year: 2020, Volume and Issue: 7(20), P. 3312 - 3342

Published: Jan. 1, 2020

This review describes recent developments in enantioselective imine reduction, including related substrates which a CN bond is the target for and in situ methods.

Language: Английский

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Recent Developments in Enantioselective Domino Reactions. Part A: Noble Metal Catalysts

Advanced Synthesis & Catalysis, Journal Year: 2023, Volume and Issue: 365(5), P. 620 - 681

Published: Jan. 17, 2023

Abstract This review updates the field of enantioselective domino reactions promoted by chiral catalysts derived from noble metals, including palladium, silver, rhodium, ruthenium, iridium and gold, published since beginning 2019. It illustrates how much a diversity these allow unprecedented asymmetric many types to be achieved with excellent enantioselectivity, giving direct access wide variety complex molecules. magnified image

Language: Английский

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Direct Synthesis of Chiral NH Lactams via Ru-Catalyzed Asymmetric Reductive Amination/Cyclization Cascade of Keto Acids/Esters

Organic Letters, Journal Year: 2020, Volume and Issue: 22(7), P. 2707 - 2713

Published: March 19, 2020

Lactams with a stereogenic center adjacent to the N atom have existed in many medicinal agents and bioactive alkaloids. Herein we report broadly applicable synthesis of enantioenriched NH lactams through one-pot asymmetric reductive amination/cyclization sequence easily available keto acids/esters. Such cascade processes alleviate demand for protecting group manipulations as well intermediate purification. This strategy is capable constructing benzo-lactams five-, six-, or seven-membered ring generally high yield excellent enantioselectivities (up 97% ee). Scalable concise syntheses key drug intermediates further displayed importance this methodology.

Language: Английский

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Iridium-catalyzed direct asymmetric reductive amination utilizing primary alkyl amines as the N-sources

Nature Communications, Journal Year: 2022, Volume and Issue: 13(1)

Published: June 10, 2022

Abstract Direct asymmetric reductive amination is one of the most efficient methods for construction chiral amines, in which scope applicable amine coupling partners remains a significant challenge. In this study we describe primary alkyl amines effectively serve as N-sources direct catalyzed by iridium precursor and sterically tunable phosphoramidite ligands. The density functional theory studies reaction mechanism imply substrates ligand strengthened (N)H-O(P) hydrogen-bonding attraction, hydride addition occurs via an outer-sphere transition state, Cl-H H-bonding plays important role. Through concise procedure, cinacalcet, tecalcet, fendiline many other related have been synthesized single step with high yields excellent enantioselectivity.

Language: Английский

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Direct Construction of Julolidines via Reductive Annulation of Quinolines and Conjugated Enones by a MOF-Derived Hierarchically Porous Iridium Catalyst

ACS Catalysis, Journal Year: 2022, Volume and Issue: 12(16), P. 10294 - 10303

Published: Aug. 5, 2022

Here, we describe the development of a MOF-derived hierarchically porous ZrO2-supported iridium catalyst (Ir-N@HP-mesoZrO2), featuring sufficient accessible catalytic sites even with ultralow loading. Such was successfully applied to selective and direct construction julolidines via reductive annulation readily available quinolines conjugated enones, proceeding good substrate functional group compatibility, reusable catalyst, high step atom efficiency, easy applicability for fabrication molecules. The present work opens door further develop useful transformations by merging hydrogen transfer-mediated activation in situ incorporation coupling sequence under heterogeneous catalysis.

Language: Английский

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Diastereoselective construction of cage-like and bridged azaheterocycles through dearomative maximization of the reactive sites of azaarenes

Organic Chemistry Frontiers, Journal Year: 2020, Volume and Issue: 8(2), P. 204 - 211

Published: Oct. 29, 2020

A highly diastereoselective multicomponent dearomative multifunctionalization of N-alkyl activated azaarenes with 1,5-diazapentadienium salts has been developed to access structurally rigid and synthetically challenging cage-like bridged azaheterocycles.

Language: Английский

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