Discovery of Organic Optoelectronic Materials Powered by Oxidative Ar–H/Ar–H Coupling

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(2), P. 1224 - 1243

Published: Jan. 4, 2024

Efficient and streamlined synthetic methods that facilitate the rapid build-up of structurally diverse π-conjugated systems are paramount importance in quest for organic optoelectronic materials. Among these methods, transition-metal-catalyzed oxidative Ar–H/Ar–H coupling reactions between two (hetero)arenes have emerged as a concise effective approach generating wide array bi(hetero)aryl fused heteroaryl structures. This innovative bypasses challenges associated with substrate pre-activation processes, thereby allowing creation frameworks were previously beyond reach using conventional Ar–X/Ar–M reactions. These inherent advantages ushered new design patterns molecules deviate from traditional methods. ground-breaking enables transcendence limitations repetitive material structures, ultimately leading to discovery novel high-performance In this Perspective, we provide an overview recent advances development materials through utilization We introduce several notable strategies domain, covering both directed non-directed strategies, dual chelation-assisted strategy ortho-C–H arylation/cyclization strategy. Additionally, shed light on role advancement Finally, discuss current existing protocols offer insights into future prospects field.

Language: Английский

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The green chemistry paradigm in modern organic synthesis

Russian Chemical Reviews, Journal Year: 2023, Volume and Issue: 92(12), P. RCR5104 - RCR5104

Published: Dec. 1, 2023

After the appearance of green chemistry concept, which was introduced in vocabulary early 1990s, its main statements have been continuously developed and modified. Currently, there are 10–12 cornerstones that should form basis for an ideal chemical process. This review analyzes accumulated experience achievements towards design products processes reduce or eliminate use generation hazardous substances. The presents views leading Russian scientists specializing various fields this subject, including homogeneous heterogeneous catalysis, fine basic organic synthesis, electrochemistry, polymer chemistry, based on bio-renewable feedstocks energetic compounds materials. A new approach to quantitative evaluation environmental friendliness by authors is described. <br> bibliography includes 1761.

Language: Английский

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Sulfoxide-Directed or 3d-Metal Catalyzed C–H Activation and Hypervalent Iodines as Tools for Atroposelective Synthesis

Accounts of Chemical Research, Journal Year: 2023, Volume and Issue: 56(3), P. 189 - 202

Published: Jan. 27, 2023

ConspectusThe expanding applications of atropisomeric compounds combined with the growing diversity such chiral molecules translate into an urgent need for innovative synthetic strategies allowing their rapid, efficient, and sustainable synthesis. Recently, C-H activation approach has provided new opportunities synthesizing axially compounds. The two complementary approaches implementation methodology toward synthesis imply either ortho-functionalization preexisting prochiral or atropo-unstable biaryl substrates direct arylation sterically encumbered aromatics. first required preinstallation a directing group on precursor, which drastically limits thus generated products. To tackle this important limitation, we have envisioned using sulfoxide as both auxiliary. Indeed, in addition to efficiently coordinating Pd-catalyst induction, moiety can be easily removed, via sulfoxide/lithium exchange, after step, guaranteeing almost unlimited postdiversification efficiency generality concept could illustrated by developing atropo-diastereoselective oxidative Heck reaction, acetoxylation, iodination, well arylation. Besides, utility was demonstrated designing expedient steganone precursor. This unique transformation also allowed us build up unprecedented triaryl scaffolds perfectly controlled axes, original skeletons ligand design. While considering atroposelective arylations, clear antagonism between harsh reaction conditions frequently coupling hindered atropo-stability product, resulted scarcity transformations. solve fundamental challenge, focused application low-valent cobalt catalyst, prompted catalyze indoles at C2 position under extremely mild (room temperature). Accordingly, C2-arylation achieved carbene delivering uncommon atropoisomerically pure excellent yields enantioselectivities. Detailed experimental theoretical mechanistic studies shed light mechanism transformation, providing strong evidence regarding origin enantioselectivity. Finally, steric hindrance guarantee molecule couple partners is limitation not only development but C-N Despite long history incredible advances Ullmann-Goldberg Buchwald-Hartwig couplings, versions transformations remained until recently. Our idea challenging issue consisted hypervalent iodines highly reactive partners, desired N-arylations occur room temperature. hypothesis validated reporting Cu-catalyzed N-arylation, λ3-iodanes partners. Subsequently, enantioselective version N-arylation successfully established Cu-complex bearing BOX ligand. In conclusion, report herein tailored-made solutions provide construct molecules, including biaryls molecules.

Language: Английский

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Atroposelective brominations to access chiral biaryl scaffolds using high-valent Pd-catalysis

Chemical Science, Journal Year: 2023, Volume and Issue: 14(13), P. 3676 - 3681

Published: Jan. 1, 2023

Compounds featuring atropisomerism are ubiquitous in natural products, therapeutics, advanced materials, and asymmetric synthesis. However, stereoselective preparation of these compounds presents many synthetic challenges. This article introduces streamlined access to a versatile chiral biaryl template through C-H halogenation reactions employing high-valent Pd catalysis combination with transient directing groups. methodology is highly scalable, insensitive moisture air, proceeds, select cases, Pd-loadings as low 1 mol%. Chiral mono-brominated, dibrominated, bromochloro biaryls prepared high yield excellent stereoselectivity. These serve remarkable building blocks bearing orthogonal handles for gamut reactions. Empirical studies elucidated regioselective activation be predicated on the oxidation state diverging site-halogenation result from cooperative effects oxidant.

Language: Английский

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Metal–Ligand Cooperation with Thiols as Transient Cooperative Ligands: Acceleration and Inhibition Effects in (De)Hydrogenation Reactions

Accounts of Chemical Research, Journal Year: 2024, Volume and Issue: 57(12), P. 1709 - 1721

Published: June 4, 2024

ConspectusOver the past two decades, we have developed a series of pincer-type transition metal complexes capable activating strong covalent bonds through mode reactivity known as metal–ligand cooperation (MLC). In such systems, an incoming substrate molecule simultaneously interacts with both center and ligand backbone, one part reacting at another ligand. The majority these feature pincer ligands pyridine core, undergo MLC reversible dearomatization/aromatization this moiety. This platform has enabled us to perform variety catalytic dehydrogenation, hydrogenation, related reactions, high efficiency selectivity under relatively mild conditions.In typical complex that operates MLC, cooperative remains coordinated throughout entire process, is only species involved in reaction. As our ongoing efforts develop new systems featuring recently introduced concept transient (TCL), i.e., when center, but coordination which rather than permanent. We thus far employed thiol(ate)s TCLs, conjunction acridanide-based ruthenium(II)-pincer catalyst, resulted remarkable acceleration inhibition effects various hydrogenation dehydrogenation reactions. A thiol(ate) can be installed situ by simple addition appropriate thiol amount equivalent been repeatedly shown enable efficient bond activation without need for other additives, base. use ancillary not fixed backbone allows system benefit from degree tunability, easily implemented varying added thiol. Importantly, thiols are coordinatively labile enough conditions leave meaningful portion catalyst its original unsaturated form, thereby allowing it carry out own characteristic activity. generates coexisting populations─one contains does not─and may lead different outcomes, namely, enhancement activity, or occurrence diverging reactivities within same reaction mixture. These achieve unique transformations, thiol-accelerated base-free aqueous methanol reforming, controlled stereodivergent semihydrogenation alkynes using inhibitor, hydrogenative perdeuteration C═C D2, combination thiol-induced inhibition. also successfully realized unprecedented formation thioesters dehydrogenative coupling alcohols thiols, well organosulfur compounds, wherein serves reactant product. Account, present overview TCL applications thiols.

Language: Английский

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Transition-metal-catalyzed C–H bond activation as a sustainable strategy for the synthesis of fluorinated molecules: an overview

Beilstein Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 19, P. 448 - 473

Published: April 17, 2023

The last decade has witnessed the emergence of innovative synthetic tools for synthesis fluorinated molecules. Among these approaches, transition-metal-catalyzed functionalization various scaffolds with a panel groups (XR

Language: Английский

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Imine induced metal-free C–H arylation of indoles

Organic Chemistry Frontiers, Journal Year: 2023, Volume and Issue: 10(24), P. 6063 - 6069

Published: Jan. 1, 2023

A simple, mild, and metal- extra-auxiliary group-free method for the direct arylation of indole-3-carbaldehydes induced by an in situ generated transient directing group was developed.

Language: Английский

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C−H Functionalization of Aldehydes and Ketones with Transient Directing Groups: Recent Developments

European Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 26(31)

Published: July 4, 2023

Abstract In order to directly functionalize C−H bonds of complex molecules and, in particular, control the regioselectivity reaction, a wide range directing groups has been used. However, these need be installed and removed for further applications, which may limit use activation synthesis. Concerning aldehydes ketones, transient group strategy recently emerged overcome this drawback. The addition an additive, general amine, allowed situ formation real achieve activation. This review presents latest developments field over period 2020–2023.

Language: Английский

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When is an Imine Directing Group a Transient Imine Directing Group in C−H Functionalization?

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: 30(25)

Published: Feb. 20, 2024

Abstract ‘Transient’ C−H functionalization has emerged in recent years to describe the use of a dynamic linkage, often an imine, direct cyclometallation and subsequent functionalization. As field continues grow popularity, we consider features that make imine directing group transient. A transient should be i) formed dynamically situ , ii) avoid discrete introduction or cleavage steps, iii) offer potential for catalysis both metal. This concept article contrasts imines with pioneering early studies as groups formation metallacycles preformed Leading developments catalytic additives form (as aldehyde amine) are covered including selected highlights most examples directed transition metals.

Language: Английский

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Native Amino Group Directed Meta-Selective C–H Arylation of Primary Amines Via Pd/Norbornene Catalysis

Organic Letters, Journal Year: 2024, Volume and Issue: 26(12), P. 2495 - 2499

Published: March 20, 2024

The selective functionalization of remote C–H bonds in free primary amines holds significant promise for the late-stage diversification pharmaceuticals. However, to date, direct meta position amine substrates lacking additional directing groups remains underexplored. In this Letter, we present a successful meta-C–H arylation derivatives using aryl iodides, resulting synthetically valuable yields. This meta-selective is achieved through sequence involving native amino-directed Pd-catalyzed seven-membered cyclometalation, followed by utilization norbornene-type transient mediator.

Language: Английский

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