Nickel‐Catalyzed Asymmetric Reductive Arylalkylation of Unactivated Alkenes

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(20), P. 6722 - 6726

Published: March 20, 2019

Abstract Reported is an asymmetric reductive dicarbofunctionalization of unactivated alkenes. Under the catalysis a Ni/BOX system, various aryl bromides, incorporating pendant olefinic unit, were successfully reacted with array primary alkyl bromides in presence Zn as reductant, furnishing series benzene‐fused cyclic compounds bearing quaternary stereocenter high enantioselectivities. Notably, this reaction avoids use pregenerated organometallics and demonstrates tolerance sensitive functionalities. The preliminary mechanistic investigations reveal that Ni‐catalyzed proceeds cascade consisting migratory insertion cross‐coupling nickel(I)‐mediated intramolecular 5‐ exo cyclization enantiodetermining step.

Language: Английский

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Enantioselective Dicarbofunctionalization of Unactivated Alkenes by Palladium‐Catalyzed Tandem Heck/Suzuki Coupling Reaction

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(41), P. 14653 - 14659

Published: Aug. 17, 2019

Abstract A highly enantioselective dicarbofunctionalization of unactivated alkenes was implemented by a Pd‐catalyzed asymmetric tandem Heck/Suzuki coupling reaction. This reaction represents the first example intramolecular cyclization/cross‐coupling olefin‐tethered aryl halides with alkyl‐, alkenyl‐ or arylboronic acids, and provides rapid access to number chiral compounds, such as dihydrobenzofurans, indolines, chromanes, indanes bearing quaternary stereocenter, in good yields excellent enantioselectivities. The practicality this validated modification biologically complex molecules peptides, piperitol, CB2 receptor agonists, etc. Moreover, synthesis two enantiomers can be easily realized simple change order steps sequence.

Language: Английский

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Enantioselective Difunctionalization of Alkenes by a Palladium‐Catalyzed Heck/Sonogashira Sequence

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(7), P. 2769 - 2775

Published: Nov. 22, 2019

Abstract Sonogashira‐type cross‐couplings are one of the most significant alkynylations in organic chemistry. One first palladium‐catalyzed intramolecular Heck/Sonogashira reactions alkenes with terminal alkynes is now reported. With this method, a variety uniquely substituted chiral benzene‐fused heterocycles bearing propargyl‐substituted all‐carbon quaternary stereocenter were obtained straightforward, high‐yielding, and highly stereoselective manner under mild conditions. Salient features process include use readily available substrates, high selectivities, broad substrate scope as well versatile product functionalizations.

Language: Английский

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Chiral N,N Ligands Enabling Palladium‐Catalyzed Enantioselective Intramolecular Heck–Matsuda Carbonylation Reactions by Sequential Migratory and CO Insertions

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(37), P. 12067 - 12070

Published: July 19, 2018

Unprecedented enantioselective intramolecular Heck carbonylation reactions of arenediazonium salts were enabled by a chiral N,N ligand. This reaction constitutes the first that proceeds through migratory insertion followed CO insertion. The enantioenriched functionalized dihydrobenzofurans obtained in good to high yields and enantiomeric ratios up 98:2 under mild operationally simple conditions.

Language: Английский

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Palladium‐Catalyzed Enantioselective Heck Carbonylation with a Monodentate Phosphoramidite Ligand: Asymmetric Synthesis of (+)‐Physostigmine, (+)‐Physovenine, and (+)‐Folicanthine

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(29), P. 12199 - 12205

Published: April 2, 2020

Abstract Reported herein is the development of first enantioselective monodentate ligand assisted Pd‐catalyzed domino Heck carbonylation reaction with CO. The highly N ‐aryl acrylamides and various nucleophiles, including arylboronic acids, anilines, alcohols, in presence CO was achieved. A novel phosphoramidite ligand, Xida‐Phos, has been developed for this it displays excellent reactivity enantioselectivity. employs readily available starting materials, tolerates a wide range functional groups, provides straightforward access to diverse array enantioenriched oxindoles having β‐carbonyl‐substituted all‐carbon quaternary stereocenters, thus providing facile complementary method asymmetric synthesis bioactive hexahydropyrroloindole its dimeric alkaloids.

Language: Английский

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Ruthenium(II)‐Catalyzed Asymmetric Inert C−H Bond Activation Assisted by a Chiral Transient Directing Group

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(9), P. 3475 - 3479

Published: Dec. 23, 2019

Abstract A ruthenium(II)‐catalyzed asymmetric intramolecular hydroarylation assisted by a chiral transient directing group has been developed. series of 2,3‐dihydrobenzofurans bearing all‐carbon quaternary stereocenters have prepared in remarkably high yields (up to 98 %) and enantioselectivities >99 % ee ). By this methodology, novel total synthesis CB2 receptor agonist MDA7 successfully

Language: Английский

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Pd/PC‐Phos‐Catalyzed Enantioselective Intermolecular Denitrogenative Cyclization of Benzotriazoles with Allenes and N‐Allenamides

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(33), P. 11444 - 11448

Published: June 14, 2019

Abstract Reported herein is an asymmetric Pd/PC‐Phos‐catalyzed denitrogenative cyclization of benzotriazoles with allenes and N‐allenamides, representing the first example enantioselective cyclizations benzotriazoles. A series optically active 3‐methyleneindolines were obtained in good yields high ee values. The use inexpensive readily available starting materials, regio‐ enantioselectivity, a broad substrate scope, mild reaction conditions, no need for base, as well versatile functionalization make this approach attractive.

Language: Английский

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Design and Synthesis of TY‐Phos and Application in Palladium‐Catalyzed Enantioselective Fluoroarylation ofgem‐Difluoroalkenes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(51), P. 22957 - 22962

Published: Sept. 25, 2020

Abstract The first example of highly enantioselective fluoroarylation gem‐difluoroalkenes with aryl halides is presented by using a new chiral sulfinamide phosphine ( Sadphos ) type ligand TY‐Phos . N‐Me‐ can be easily synthesized on gram scale from readily available starting materials in three steps. Salient features this work including materials, good yields, high enantioselectivities as well broad substrate scope make approach very practical and attractive. Notably, the asymmetric synthesis an analogue biologically active molecule also reported.

Language: Английский

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Sequential Pd⁰‐ and Pd^II‐Catalyzed Cyclizations: Enantioselective Heck and Nucleopalladation Reactions

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(37), P. 20231 - 20236

Published: July 9, 2021

An enantioselective consecutive cyclization/coupling process, catalyzed by palladium is reported. Stereoinduction arises from an carbopalladation, generating intermediate which promotes a nucleopalladation step. The dual cyclization sequence was compatible with variety of alkyne-tethered oxygen- and nitrogen-centered nucleophiles, alkenyl-tethered aryl iodides, to forge numerous bisheterocycles in good yields high regio- enantioselectivities.

Language: Английский

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Enantioselective Synthesis of Isoxazolines Enabled by Palladium‐Catalyzed Carboetherification of Alkenyl Oximes

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(11), P. 4421 - 4427

Published: Dec. 23, 2019

Reported here is a highly efficient Pd/Xiang-Phos catalyzed enantioselective carboetherification of alkenyl oximes with either aryl or halides, delivering various chiral 3,5-disubstituted and 3,5,5-trisubstituted isoxazolines in good yields up to 97 % ee. The sterically bulky electron-rich (S,Rs)-NMe-X2 ligand responsible for the excellent reactivities enantioselectivities. salient features this transformation include mild reaction conditions, general substrate scope, functional-group tolerance, yields, high enantioselectivities, easy scale-up, application late-stage modification bioactive compounds. obtained products can be readily transformed into useful 1,3-aminoalcohols.

Language: Английский

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