Nitrene Transfer and Carbene Transfer in Gold Catalysis

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(14), P. 9039 - 9112

Published: Aug. 3, 2020

Catalytic transformations involving metal carbenes are considered one of the most important aspects homogeneous transition catalysis. Recently, gold-catalyzed generation gold from readily available alkynes represents a significant advance in carbene chemistry. This Review summarizes advances nitrene-transfer reactions with nitrogen-transfer reagents, such as azides, nitrogen ylides, isoxazoles, and anthranils, carbene-transfer reactions, oxygen atom-transfer nitro compounds, nitrones, sulfoxides, pyridine N-oxides, through presumable α-imino α-oxo intermediates, respectively. Gold-catalyzed processes reviewed by highlighting their product diversity, selectivity, applicability, mechanistic rationale is presented where possible.

Language: Английский

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Gold-Catalyzed Reactions of Specially Activated Alkynes, Allenes, and Alkenes

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(14), P. 8756 - 8867

Published: Nov. 23, 2020

This review describes the gold-catalyzed reactions of specially activated alkynes, allenes, and alkenes. Such species are characterized by presence either electron-donating or electron-withdrawing groups as substituents carbon π-system. They intrinsically polarized, when compared to their nonspecially counterparts can therefore be involved in transformations featuring increased regio-, stereo-, chemoselectivities. The chemistry π-systems under homogeneous gold catalysis is extremely rich varied. reactivity observed with unsaturated systems often transposed ones without loss efficiency. However, also exhibit specific reactivities that cannot attained regular substrates. In this family π-systems, ynamides analogs, along alkynyl carbonyl derivatives, classes substrates have retained most attention. provides an overview developed all discussing general reactivities, presenting commenting on well applications.

Language: Английский

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Recent Advances in Gold(III) Chemistry: Structure, Bonding, Reactivity, and Role in Homogeneous Catalysis

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(14), P. 8364 - 8451

Published: Sept. 23, 2020

Over the past decade organometallic chemistry of gold(III) has seen remarkable advances. This includes synthesis first examples several compound classes that have long been hypothesized as being part catalytic cycles, such alkene, alkyne, CO and hydride complexes, important catalysis-relevant reaction steps at last demonstrated for gold, like migratory insertion β-H elimination reactions. Also, pathways were already known, example generation intermediates by oxidative addition their reductive elimination, are much better understood. A deeper understanding fundamental reactivity revealed unexpected mechanistic avenues, which can open when barriers reactions other metals would be regarded "standard" too high. review summarizes evaluates these developments, together with applications in catalysis, emphasis on insight gained investigations.

Language: Английский

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Gold-Catalyzed Synthesis of Small Rings

Chemical Reviews, Journal Year: 2020, Volume and Issue: 121(14), P. 8613 - 8684

Published: Nov. 2, 2020

Three- and four-membered rings, widespread motifs in nature medicinal chemistry, have fascinated chemists ever since their discovery. However, due to energetic considerations, small rings are often difficult assemble. In this regard, homogeneous gold catalysis has emerged as a powerful tool construct these highly strained carbocycles. This review aims provide comprehensive summary of all the major advances discoveries made gold-catalyzed synthesis cyclopropanes, cyclopropenes, cyclobutanes, cyclobutenes, corresponding heterocyclic or heterosubstituted analogs.

Language: Английский

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Reactivity of ynamides in catalytic intermolecular annulations

Chemical Society Reviews, Journal Year: 2020, Volume and Issue: 50(4), P. 2582 - 2625

Published: Dec. 24, 2020

This review comprehensively summarizes the advances achieved in catalytic intermolecular annulations of ynamides from 2010 to 2020.

Language: Английский

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Acyl Migration versus Epoxidation in Gold Catalysis: Facile, Switchable, and Atom‐Economic Synthesis of Acylindoles and Quinoline Derivatives

Angewandte Chemie International Edition, Journal Year: 2019, Volume and Issue: 59(1), P. 471 - 478

Published: Oct. 17, 2019

Abstract We report a switchable synthesis of acylindoles and quinoline derivatives via gold‐catalyzed annulations anthranils ynamides. α‐Imino gold carbenes, generated in situ from an N,O‐coordinated gold(III) catalyst, undergo electrophilic attack to the aryl π‐bond, followed by unexpected highly selective 1,4‐ or 1,3‐acyl migrations form 6‐acylindoles 5‐acylindoles. With (2‐biphenyl)di‐ tert ‐butylphosphine (JohnPhos) ligand, gold(I) carbenes experienced carbene/carbonyl additions deliver oxides. Some these epoxides are valuable substrates for preparation 3‐hydroxylquinolines, quinolin‐3(4 H )‐ones, polycyclic compounds facile rearrangements. The reaction can be efficiently conducted on gram scale obtained products preparing other potentially useful compounds. A computational study explained selectivities dependency pathway oxidation state ligands gold. barrier formation strained oxirane ring is too high; whereas with this transition becomes accessible. Furthermore, energetic barriers migration substituents intermediate sigma‐complexes support observed substitution pattern final product.

Language: Английский

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α‐Imino Gold Carbene Intermediates from Readily Accessible Sulfilimines: Intermolecular Access to Structural Diversity

Chemistry - A European Journal, Journal Year: 2019, Volume and Issue: 26(15), P. 3197 - 3204

Published: Dec. 3, 2019

Abstract Catalytic approaches to pharmaceutically important bioactive skeletons through gold carbene intermediates have experienced a dramatic development in the last decade. Although various precursors continue play an role heterocyclic syntheses, these reagents are associated with some drawbacks terms of functional group tolerance, synthetic methods and safety limitations. A new generation nitrene transfer was established 2019: sulfilimines. These safe, inexpensive readily available. They can conveniently be stored handled, thus represent ideal for fast modular modification scaffolds preparation libraries by intermolecular reactions two components. Both practical synthesizing sulfilimines versatility ylidic species gold‐catalyzed structural diversity, both heterocycles carbocycles, will outlined this Concept article.

Language: Английский

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Gold‐Catalyzed Oxidative Alkyne Functionalization by N−O/S−O/C−O Bond Oxidants

Advanced Synthesis & Catalysis, Journal Year: 2020, Volume and Issue: 362(18), P. 3664 - 3708

Published: May 11, 2020

Abstract Since the beginning of this century, homogeneous gold‐catalyzed alkyne transformations have been an active area research in pursuit developing efficient synthetic methodologies. This emerging which at exploited mild Lewis acid character gold and its propensity to form π‐complex with alkyne, has reinvigorated upon discovery oxidative functionalization 2007. The oxidation enabled direct access α‐oxo carbenes alkynal complex versatile reactivity applied achieve including but not limited oxyarylation, C−H, X−H (X=N, O) insertion, cyclization, cycloaddition, ring expansion, various cascade reactions. review provides a comprehensive summary methods, applications mechanistic insight by N−O/S−O/C−O bond oxidants covering literature reports appeared since magnified image

Language: Английский

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Anthranils: versatile building blocks in the construction of C–N bonds and N-heterocycles

Organic Chemistry Frontiers, Journal Year: 2020, Volume and Issue: 7(9), P. 1177 - 1196

Published: Jan. 1, 2020

This review article provides an overview of the recent progress in transformations anthranils, which have emerged as versatile building blocks assembly various C–N bonds and medicinally active heterocyclic systems.

Language: Английский

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Transition Metal‐Catalysed Direct C−H Bond Functionalizations of 2‐Pyridone Beyond C3‐Selectivity

Chemistry - An Asian Journal, Journal Year: 2020, Volume and Issue: 15(14), P. 2092 - 2109

Published: June 5, 2020

2-Pyridone is a ubiquitous motif in natural products, drug molecules, ligands catalysis and organic materials. There necessity of direct step-economic methods for the construction 2-pyridone based molecules. Strategically, primary developments have led to C3-functionalizations due inherent reactivity this center. Despite this, many elegant transition metal-catalysed been established introduce versatile functional groups at C4, C5 C6-position via C-H bond functionalizations. This minireview focuses on categorized introduction different scaffolds beyond C3-selectivity discusses substrate scope, limitations plausible mechanistic details.

Language: Английский

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