Pyrazolone: a powerful synthon for asymmetric diverse derivatizations

Chemical Communications, Journal Year: 2018, Volume and Issue: 54(82), P. 11515 - 11529

Published: Jan. 1, 2018

As a powerful synthon, pyrazolone has widely been exploited for the construction of various chiral pyrazoles/pyrazolones which hold great potential in development pharmaceutical chemistry, coordination chemistry and functional materials. Benefited from diversity multiple active sites starting materials, such as 4-nonsubstituted/4-monosubstituted pyrazolones α,β-unsaturated pyrazolones, large numbers strategies asymmetric synthesis have developed successfully past few years. This feature article summarizes these excellent research studies since 2015, including some efforts by our group. Based on structural final products, this is divided into four sections, catalytic 4-monosubstituted, 4-disubstituted, fused spiro pyrazoles/pyrazolones. Schematic illustrations are given representative examples each section.

Language: Английский

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Pentamethylcyclopentadienyl rhodium(III)–chiral disulfonate hybrid catalysis for enantioselective C–H bond functionalization

Nature Catalysis, Journal Year: 2018, Volume and Issue: 1(8), P. 585 - 591

Published: July 20, 2018

Language: Английский

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Chiral Carboxylic Acid Enabled Achiral Rhodium(III)‐Catalyzed Enantioselective C−H Functionalization

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(37), P. 12048 - 12052

Published: July 24, 2018

Reported is an achiral Cpx RhIII /chiral carboxylic acid catalyzed asymmetric C-H alkylation of diarylmethanamines with a diazomalonate, followed by cyclization and decarboxylation to afford 1,4-dihydroisoquinolin-3(2H)-one. Secondary alkylamines as well nonprotected primary underwent the transformation high enantioselectivities (up 98.5:1.5 e.r.) using newly developed chiral sole source chirality achieve enantioselective cleavage concerted metalation-deprotonation mechanism.

Language: Английский

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Tailored trisubstituted chiral Cp^xRh^III catalysts for kinetic resolutions of phosphinic amides

Chemical Science, Journal Year: 2018, Volume and Issue: 9(11), P. 2981 - 2985

Published: Jan. 1, 2018

A trisubstituted chiral Cp^x ligand family is introduced.

Language: Английский

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Enantioselective Formal C(sp³)−H Bond Activation in the Synthesis of Bioactive Spiropyrazolone Derivatives

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 58(1), P. 307 - 311

Published: Oct. 17, 2018

Abstract Herein, we report the first enantioselective annulation of α‐arylidene pyrazolones through a formal C(sp 3 )−H activation under mild conditions enabled by highly variable Rh III ‐Cp x catalysts. The method has wide substrate scope and proceeds with good to excellent yields enantioselectivities. Its synthetic utility was demonstrated late‐stage functionalization drugs natural products as well preparation enantioenriched [3]dendralenes. Preliminary biological investigations also identified spiropyrazolones novel class Hedgehog pathway inhibitors.

Language: Английский

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Rhodium(III)‐Catalyzed Atroposelective Synthesis of Biaryls by C−H Activation and Intermolecular Coupling with Sterically Hindered Alkynes

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(32), P. 13288 - 13294

Published: April 16, 2020

Abstract Reported herein is the atroposelective synthesis of biaryl NH isoquinolones by Rh III ‐catalyzed C−H activation benzamides and intermolecular [4+2] annulation for a broad scope 2‐substituted 1‐alkynylnaphthalenes, as well sterically hindered, symmetric diarylacetylenes. The axial chirality constructed based on dynamic kinetic transformation alkyne in redox‐neutral with benzamides, insertion being stereodetermining. reaction accommodates both heteroaryl carboxamides proceeds excellent regioselectivity (if applicable) enantioselectivities (average 91.8 % ee ). An enantiomerically diastereomerically pure rhodacyclic complex was prepared offers insight into enantiomeric control coupling system, wherein steric interactions between amide directing group substrate dictate regio‐ enantioselectivity.

Language: Английский

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Chiral Transient Directing Groups in Transition-Metal-Catalyzed Enantioselective C–H Bond Functionalization

ACS Catalysis, Journal Year: 2020, Volume and Issue: 10(21), P. 12898 - 12919

Published: Oct. 21, 2020

Transition-metal-catalyzed C–H bond functionalization has known a rapid evolution in the last years, offering modern strategies for reaching high molecular complexity step- and atom-economical way. Despite indisputable advances, selectivity issues still remain, given ubiquity of bonds on molecules; thus, several approaches have been developed to tackle this challenge. Among them, use transient directing group emerged as an effective tool, circumventing need extra synthetic steps install then cleave molecule. More recently, strategy successfully applied even more challenging transition-metal-catalyzed enantioselective functionalization. This review will highlight discuss main advances made chiral C(sp2)–H C(sp3)–H by transition-metal catalysis.

Language: Английский

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C−H Bond Activation for the Synthesis of Heterocyclic Atropisomers Yields Hedgehog Pathway Inhibitors

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(43), P. 14250 - 14254

Published: Sept. 11, 2018

Abstract Axially chiral 4‐arylisoquinolones are endowed with pronounced bioactivity, and methods for their efficient synthesis have gained widespread attention. However, enantioselective of axially by means C−H activation has not been reported to date. Described here is a rhodium (III)‐catalyzed bond annulation the atroposelective 4‐arylisoquinolones. The method employs cyclopentadienyl ligands embodying piperidine ring as backbone yields atropisomers good excellent enantioselectivity. Biological relevance was demonstrated investigation in different cellular assays, leading discovery novel non‐SMO (SMO= smoothened) binding Hedgehog pathway inhibitors.

Language: Английский

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Rhodium‐Catalyzed Enantioselective Oxidative [3+2] Annulation of Arenes and Azabicyclic Olefins through Twofold C−H Activation

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 58(49), P. 17666 - 17670

Published: Sept. 24, 2019

Abstract C−H bond activation is mostly limited to ortho selectivity. Activation of both and meta bonds constitutes a particularly important strategy for annulation, but has rarely been studied in enantioselective systems. Reported herein rhodium(III)‐catalyzed asymmetric [3+2] transannulation arenes with 7‐azabenzonorbornadienes. Two distinct classes have identified as substrates, the coupling proceeded high enantioselectivity excellent diastereoselectivity through sequential bonds.

Language: Английский

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Rhodium(III)‐Catalyzed Asymmetric Access to Spirocycles through C−H Activation and Axial‐to‐Central Chirality Transfer

Angewandte Chemie International Edition, Journal Year: 2020, Volume and Issue: 59(18), P. 7188 - 7192

Published: Feb. 3, 2020

Axial-to-central chirality transfer is an important strategy to construct chiral centers, where the axially reagents are mostly limited atropomerically stable ones. Reported herein a RhIII -catalyzed enantioselective spiroannulative synthesis of nitrones. The coupling proceeds via C-H arylation give metastable biaryl, followed by intramolecular dearomative trapping under oxidative conditions with high degree transfer.

Language: Английский

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