Iridium-Catalyzed Asymmetric Allylic Substitution Reactions

Chemical Reviews, Journal Year: 2018, Volume and Issue: 119(3), P. 1855 - 1969

Published: Dec. 24, 2018

In this review, we summarize the origin and advancements of iridium-catalyzed asymmetric allylic substitution reactions during past two decades. Since first report in 1997, Ir-catalyzed have attracted intense attention due to their exceptionally high regio- enantioselectivities. been significantly developed recent years many respects, including ligand development, mechanistic understanding, substrate scope, application synthesis complex functional molecules. an explicit outline ligands, mechanism, scope nucleophiles, applications is presented.

Language: Английский

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Recent Advances in the Synthesis of β-Carboline Alkaloids

Molecules, Journal Year: 2021, Volume and Issue: 26(3), P. 663 - 663

Published: Jan. 27, 2021

β-Carboline alkaloids are a remarkable family of natural and synthetic indole-containing heterocyclic compounds they widely distributed in nature. Recently, these have been the focus interest, thanks to their diverse biological activities. Their pharmacological activity makes them desirable as sedative, anxiolytic, hypnotic, anticonvulsant, antitumor, antiviral, antiparasitic or antimicrobial drug candidates. The growing potential inherent encourages many researchers address challenges synthesis products containing complex β-carboline frameworks. In this review, we describe recent developments closely related derivatives through selected examples from last 5 years. is on key steps with improved procedures approaches. Furthermore also highlighted.

Language: Английский

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Ketones and Aldehydes asO-Nucleophiles in Iridium-Catalyzed Intramolecular Asymmetric Allylic Substitution Reaction

Journal of the American Chemical Society, Journal Year: 2019, Volume and Issue: 141(6), P. 2228 - 2232

Published: Jan. 28, 2019

Ketones and aldehydes are employed as enol O-nucleophiles in an iridium-catalyzed asymmetric allylic substitution reaction. The reaction proceeds well the presence of a well-defined chiral iridium complex under mild conditions. A series 2H-1,4-oxazine skeletons can be obtained up to 94% yield with 99% ee. utility this novel method has been demonstrated by its implementation first enantioselective synthesis (+)-chelonin A.

Language: Английский

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Intramolecular Heck Reaction in Total Synthesis of Natural Products: An Update

European Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 2021(14), P. 2057 - 2076

Published: Feb. 19, 2021

Abstract This review highlights the application of intramolecular Heck reaction in total synthesis natural products which were successfully synthesized recent years (2013 to 2019). cyclization was used as one strategic steps for constructions wide variety cyclic scaffolds essential preparation different products.

Language: Английский

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Bioinspired Oxidative Cyclization of the Geissoschizine Skeleton for the Total Synthesis of (−)‐17‐nor‐Excelsinidine

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(38), P. 12294 - 12298

Published: March 25, 2018

We report the first total synthesis of (-)-17-nor-excelsinidine, a zwitterionic monoterpene indole alkaloid that displays an unusual N4-C16 connection. Inspired by postulated biosynthesis, we explored oxidative coupling approach from geissoschizine framework to forge key ammonium-acetate Two strategies allowed us achieve this goal, namely intramolecular nucleophilic substitution on 16-chlorolactam with N4 nitrogen atom or direct I2 -mediated enolate geissoschizine.

Language: Английский

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Trimethyl Orthoacetate and Ethylene Glycol Mono‐Vinyl Ether as Enolate Surrogates in Enantioselective Iridium‐Catalyzed Allylation

Angewandte Chemie International Edition, Journal Year: 2018, Volume and Issue: 57(26), P. 7654 - 7658

Published: May 2, 2018

Abstract Trimethyl orthoacetate and ethylene glycol mono‐vinyl ether are employed in iridium‐catalyzed enantioselective allylation reactions. The method documented enables their convenient use as surrogates for silyl ketene acetals enol ethers to prepare γ,δ‐unsaturated esters protected aldehydes with excellent enantioselectivity. utility of this novel has been demonstrated by its implementation a formal synthesis the meroterpenoid (+)‐conicol.

Language: Английский

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Catalytic enantioselective nitrone cycloadditions enabling collective syntheses of indole alkaloids

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: July 31, 2024

Abstract Tetrahydro-β-carboline skeletons are prominent and ubiquitous in an extraordinary range of indole alkaloid natural products pharmaceutical compounds. Powerful synthetic approaches for stereoselective synthesis tetrahydro-β-carboline have immense impacts attracted enormous attention. Here, we outline a general chiral phosphoric acid catalyzed asymmetric 1,3-dipolar cycloaddition 3,4-dihydro-β-carboline-2-oxide type nitrone that enables access to three types tetrahydro-β-carbolines bearing continuous multi-chiral centers quaternary centers. The method displays different endo/exo selectivity from traditional chemistry. distinct power this strategy has been illustrated by application collective enantiodivergent total syntheses 40 tetrahydro-β-carboline-type with divergent stereochemistry varied architectures.

Language: Английский

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Short Synthesis of the Monoterpene Indole Alkaloid (±)-Arbornamine

The Journal of Organic Chemistry, Journal Year: 2018, Volume and Issue: 83(8), P. 4867 - 4870

Published: March 28, 2018

The first total synthesis of the monoterpene indole alkaloid (±)-arbornamine (1) has been completed, which proceeds in only 6 steps and 31% overall yield from three readily available, known compounds. features a cascade involving Pictet–Spengler cyclization/intramolecular ammonolysis to create tetracyclic core arbornamine single chemical operation. subsequent elaboration 5 into 1 was effected by key reductive Heck reaction global reduction.

Language: Английский

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Monoterpene indole alkaloids with acetylcholinesterase inhibitory activity from the leaves of Rauvolfia vomitoria

Bioorganic Chemistry, Journal Year: 2020, Volume and Issue: 102, P. 104136 - 104136

Published: July 23, 2020

Language: Английский

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Catalytic Asymmetric Alkynylation of 3,4‐Dihydro‐β‐carbolinium Ions Enables Collective Total Syntheses of Indole Alkaloids

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(47), P. 25135 - 25142

Published: Sept. 28, 2021

Chiral tetrahydro-β-carboline (THβC) is not only a prevailing structural feature of many natural alkaloids but also versatile synthetic precursor for vast array monoterpenoid indole alkaloids. Asymmetric synthesis C1-alkynyl THβCs remains rarely explored and challenging. Herein, we describe the development two complementary approaches catalytic asymmetric alkynylation 3,4-dihydro-β-carbolinium ions with up to 96 % yield 99 ee. The utility chiral was demonstrated by collective total syntheses seven alkaloids: harmicine, eburnamonine, desethyleburnamonine, larutensine, geissoschizol, geissochizine, akuammicine.

Language: Английский

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