Thianthrenium-enabled sulfonylation via electron donor-acceptor complex photoactivation

Chem Catalysis, Год журнала: 2022, Номер 2(4), С. 898 - 907

Опубликована: Апрель 1, 2022

Sulfone-containing compounds are prevalent building blocks in pharmaceutical agents and other biomolecules, they serve as key intermediates the synthesis of complex scaffolds. During past decade, several methods have been developed to access sulfones. These strategies, however, require use strong reaction conditions, limiting their substrate scope. Recently, visible-light-mediated transformations emerged novel platforms unprecedented structural motifs. This report demonstrates thianthrenium-enabled sulfonylation via intra-complex charge transfer generate transient aryl- persistent sulfonyl radicals that undergo selective coupling alkyl- (hetero)aryl sulfones under ambient conditions. strategy allows retention halide handles, presenting a complementary approach transition metal-mediated photoredox couplings. Furthermore, this high functional group tolerance is amenable late-stage functionalization biomolecules. Mechanistic investigations support intermediacy electron donor-acceptor (EDA) complexes.

Язык: Английский

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Recent Advances in Thianthrenation/Phenoxathiination Enabled Site-Selective Functionalization of Arenes

Synthesis, Год журнала: 2022, Номер 54(18), С. 3928 - 3940

Опубликована: Июнь 28, 2022

Abstract Site-selective functionalization of simple arenes remains a paramount challenge due to the similarity multiple C–H bonds in same molecule with similar steric environment and electronic properties. Recently, site-selective thianthrenation/phenoxathiination has become an attractive solution reach this challenging goal it been applied late-stage various bioactive molecules. This short review aims summarize recent advances via aryl thianthrenium salts, as well mechanistic insights remarkable site-selectivity obtained thianthrenation step. 1 Introduction 2 Site-Selective Thianthrenation Arenes Mechanistic Insight 3 Thianthrenation-Enabled Functionalization 3.1 C(sp 2)–C Bond Formation Reaction 3.2 2)–X 4 Conclusion Outlook

Язык: Английский

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Intermolecular Metal‐Free Cyclopropanation and Aziridination of Alkenes with XH₂(X=N, C) by Thianthrenation**

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(41)

Опубликована: Авг. 17, 2022

Three-membered cyclic structures are widely existing in natural products and serve as enabling intermediates organic synthesis. However, the efficient straightforward access to such with diversity remains a formidable challenge. Herein, general practical protocol aziridines cyclopropanes synthesis using free XH2 (X=C or N) alkenes by thianthrenation is presented. This metal-free features direct aziridination cyclopropanation unprotected . Free sulfonamides, amides, carbamates, amines, methylene acidic protons, good precursors, providing an attractive alternative for of from easily available starting materials.

Язык: Английский

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Copper‐Catalyzed Carboxylation of Aryl Thianthrenium Salts with CO₂

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(47)

Опубликована: Окт. 5, 2022

Carboxyl group is one of the most widely used groups in organic synthesis. Herein, an efficient copper-catalyzed carboxylation aryl thianthrenium salts with carbon dioxide (CO2 ) at room temperature has been developed. The reaction employs low loading cuprous chloride catalyst under 1 atm CO2 and exhibits good functional tolerance. In combination C-H thianthrenation aromatic hydrocarbons, this work provides method for site-selective hydrocarbons. It may serve as a significant late-stage tool modification drug molecules future.

Язык: Английский

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Synthesis of Arynes via Formal Dehydrogenation of Arenes

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(6), С. 3306 - 3311

Опубликована: Фев. 2, 2023

Arynes offer immense potential for diversification of benzenoid rings, which occur in pharmaceuticals, agrochemicals, and liquid crystals. However, accessing these high-energy intermediates requires synthetic precursors, involve either harsh conditions or multistep syntheses. The development alternative methods to access arynes using simpler substrates milder is necessary a more streamlined approach. Here, we describe two-step formal dehydrogenation simple arenes generate at remote position relative traditionally reactive groups, e.g., halides. This approach enabled by regioselective installation ejection an "onium" leaving group, demonstrate the compatibility (20 examples) arynophiles (8 examples). Moreover, through direct comparison, show that our method both functional group tolerant efficient generating than current state-of-the-art aryne precursors. Finally, opportunities C-H amination are distinct from other methods.

Язык: Английский

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Metallaphotoredox deuteroalkylation utilizing thianthrenium salts

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Июнь 13, 2024

Abstract Deuterium labeling compounds play a crucial role in organic and pharmaceutical chemistry. The synthesis of such typically involves deuterated building blocks, allowing for the incorporation deuterium atoms functional groups into target molecule single step. Unfortunately, limited availability synthetic approaches to synthons has impeded progress this field. Here, we present an approach utilizing alkyl-substituted thianthrenium salts that efficiently selectively introduce at α position alkyl chains through pH-dependent HIE process, using D 2 O as source. resulting α-deuterated salts, which bear two atoms, exhibit excellent selectivity electrophilic substitution reactions. Through situ formation isotopically labelled halides, these demonstrate compatibility series metallaphotoredox cross-electrophile coupling with (hetero)aryl, alkenyl, bromides, other salts. Our technique allows wide range substrates, high incorporation, precise control over site insertion within benzyl position, allylic or any chain between, well neighboring heteroatoms. This makes it invaluable synthesizing various deuterium-labeled compounds, especially those significance.

Язык: Английский

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Dibenzothiophenium Salts: Practical Alternatives to Hypervalent I(III)-Based Reagents

Accounts of Chemical Research, Год журнала: 2025, Номер unknown

Опубликована: Фев. 2, 2025

ConspectusDuring the past few years, interest among organic synthesis practitioners in use of sulfonium salts has exponentially growth. This can arguably be attributed to a series specific factors: (a) The recent development more direct and efficient protocols for these species, which make reagents wide structural variety easily available multigram scale. (b) recognition that reactivity resembles hypervalent iodine compounds, therefore, they used as effective replacement such species most their applications. (c) Their intrinsic thermal stability tolerance air moisture, clearly surpass I(III)-reagents analogue reactivity, facilitate purification, isolation well-defined storage, safely handling on larger (d) Finally, possibility further functionalize once sulfur-containing platform been incorporated. Specifically, this last synthetic approach is not trivial when working with I(III)-species facilitates access no counterpart I(III) realm.This renewed led improvement already existing transformations well discovery unprecedented ones; particular, by incorporate partners traditional cross-coupling C–H activation steps or combine them modern technologies photocatalysis electrosynthesis. In Account, originally prepared our laboratory will outlined compared I(III)-counterparts. Some are now commercially available, started spread widely across chemistry community, helping speed process identification potentially bioactive products new functionaliced materials. However, challenges still remain. characterized an optimal balance between site-selectivity, showing broader compatibility toward sensitive functional groups need. addition, often makes necessary (sophisticated) catalysts activate latent hidden structures. Although priori one see fact disadvantage, it might actually decisive harvest full potential because surely preparation operational context I(III)-chemistry. If becomes true, may contribute expediting retrosynthetic disconnections that, date, impossible.

Язык: Английский

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Sulfur(IV) in Transition-Metal-Free Cross-Couplings for Biaryl Synthesis

ACS Sustainable Chemistry & Engineering, Год журнала: 2022, Номер 10(8), С. 2569 - 2586

Опубликована: Фев. 16, 2022

The reactivity of sulfur(IV) compounds is great current interest among organic chemists. In this Perspective, we discuss the chemistry (namely, sulfoxides, sulfonium salts, and sulfinates) within area transition-metal-free cross-couplings for biaryl synthesis. These sulfur(IV)-based methods show potential in sustainable formation can deliver unique structures that are difficult to access by other means. This Perspective also highlights how versatile has helped design new reagents, mediators, catalysts.

Язык: Английский

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Visible-light-initiated catalyst-free trifluoromethylselenolation of arylsulfonium salts with [Me₄N][SeCF₃]

Organic Chemistry Frontiers, Год журнала: 2022, Номер 9(8), С. 2220 - 2227

Опубликована: Янв. 1, 2022

Catalyst-free visible-light irradiation has leveraged the big redox potential gaps between arylsulfonium salts and [Me 4 N][SeCF 3 ], which combined with sulfenylation processes offers convenient selective C–H trifluoromethylselenolation.

Язык: Английский

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Catalyst-Free C(sp²)-H Borylation through Aryl Radical Generation from Thiophenium Salts via Electron Donor–Acceptor Complex Formation

Organic Letters, Год журнала: 2022, Номер 24(40), С. 7434 - 7439

Опубликована: Окт. 3, 2022

Aryl borates lie at the heart of carbon–carbon bond couplings, and they are widely applied to synthesis functional materials, pharmaceutical compounds, natural products. Currently, synthetic methods for aryl mostly limited metal-catalyzed routes, nonmetallic strategies remain comparatively underdeveloped. Herein, we report a mild, scalable, visible-light-induced cross-coupling between dibenzothiophenium triflate salts bis(catecholato)-diboron construction C–B bonds in absence base, transition metal–ligand complex, or photoredox catalyst. Mechanistic studies reveal that this transformation is achieved through an electron donor–acceptor (EDA) complex activation The mild reaction conditions allow preparation aromatic good yields with excellent group tolerance. This photochemical protocol was also successfully late-stage modification products drug intermediate, greatly demonstrating broadened utility.

Язык: Английский

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