Carbon Atom Insertion into Pyrroles and Indoles Promoted by Chlorodiazirines

Journal of the American Chemical Society, Год журнала: 2021, Номер 143(30), С. 11337 - 11344

Опубликована: Июль 21, 2021

Herein, we report a reaction that selectively generates 3-arylpyridine and quinoline motifs by inserting aryl carbynyl cation equivalents into pyrrole indole cores, respectively. By employing α-chlorodiazirines as thermal precursors to the corresponding chlorocarbenes, traditional haloform-based protocol central parent Ciamician-Dennstedt rearrangement can be modified directly afford 3-(hetero)arylpyridines quinolines. Chlorodiazirines are conveniently prepared in single step oxidation of commercially available amidinium salts. Selectivity function substitution pattern was examined, predictive model based on steric effects is put forward, with DFT calculations supporting selectivity-determining cyclopropanation step. Computations surprisingly indicate stereochemistry little consequence subsequent electrocyclic ring opening forges pyridine core, due compensatory homoaromatic stabilization counterbalances orbital-controlled torquoselectivity effects. The utility this skeletal transform further demonstrated through preparation quinolinophanes editing pharmaceutically relevant pyrroles.

Язык: Английский

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A radical approach for the selective C–H borylation of azines

Nature, Год журнала: 2021, Номер 595(7869), С. 677 - 683

Опубликована: Май 20, 2021

Язык: Английский

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Skeletal Editing: Interconversion of Arenes and Heteroarenes

Helvetica Chimica Acta, Год журнала: 2023, Номер 106(3)

Опубликована: Янв. 13, 2023

Abstract Skeletal editing involves making specific point‐changes to the core of a molecule through selective insertion, deletion or exchange atoms. It thus represents potentially powerful strategy for step‐economic modification complex substrates and is perfect complement methods such as C−H functionalization that target molecular periphery. Given their ubiquity in biologically active compounds, ability perform skeletal on – therefore interconvert between aromatic heterocycles especially valuable. This review summarizes both recent key historical examples applied interconversion rings; we anticipate it will serve highlight not only innovative enabling nature current methods, but also tremendous opportunities still exist field.

Язык: Английский

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Overcoming Limitations in Decarboxylative Arylation via Ag–Ni Electrocatalysis

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(38), С. 17709 - 17720

Опубликована: Сен. 15, 2022

A useful protocol for achieving decarboxylative cross-coupling (DCC) of redox-active esters (RAE, isolated or generated in situ) and halo(hetero)arenes is reported. This pragmatically focused study employs a unique Ag-Ni electrocatalytic platform to overcome numerous limitations that have plagued this strategically powerful transformation. In its optimized form, coupling partners can be combined surprisingly simple way: open the air, using technical-grade solvents, an inexpensive ligand Ni source, substoichiometric AgNO3, proceeding at room temperature with commercial potentiostat. Most importantly, all results are placed into context by benchmarking state-of-the-art methods. Applications presented simplify synthesis rapidly enable access challenging chemical space. Finally, adaptation multiple scale regimes, ranging from parallel milligram-based decagram recirculating flow presented.

Язык: Английский

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Boryl radical-mediated halogen-atom transfer enables arylation of alkyl halides with electrophilic and nucleophilic coupling partners

Nature Synthesis, Год журнала: 2024, Номер 3(10), С. 1221 - 1230

Опубликована: Июль 1, 2024

Язык: Английский

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Boron-containing helicenes as new generation of chiral materials: opportunities and challenges of leaving the flatland

Chemical Science, Год журнала: 2024, Номер 15(20), С. 7408 - 7440

Опубликована: Янв. 1, 2024

Recent advances in synthesis have opened the way to a variety of boron helicenes. We highlight main achievements these chiral compounds and discuss their photophysical properties potential as functional materials.

Язык: Английский

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The 2‐Pyridyl Problem: Challenging Nucleophiles in Cross‐Coupling Arylations

Angewandte Chemie International Edition, Год журнала: 2020, Номер 60(20), С. 11068 - 11091

Опубликована: Сен. 17, 2020

Azine-containing biaryls are ubiquitous scaffolds in many areas of chemistry, and efficient methods for their synthesis continually desired. Pyridine rings prominent amongst these motifs. Transition-metal-catalysed cross-coupling reactions have been widely used functionalisation as they often provide a swift tuneable route to related biaryl scaffolds. However, 2-pyridine organometallics capricious coupling partners 2-pyridyl boron reagents particular notorious instability poor reactivity Suzuki-Miyaura reactions. The pyridine-containing is therefore limited, the formation unsymmetrical 2,2'-bis-pyridines scarce. This Review focuses on developed challenging nucleophiles with (hetero)aryl electrophiles, ranges from traditional processes alternative nucleophilic novel main group approaches.

Язык: Английский

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Emerging Building Blocks for Medicinal Chemistry: Recent Synthetic Advances

European Journal of Organic Chemistry, Год журнала: 2021, Номер 2021(47), С. 6478 - 6510

Опубликована: Сен. 8, 2021

Abstract Current medicinal chemistry relies heavily on the quality of building blocks, i. e. reagents used to introduce chemical diversity into target molecules. The last decade witnessed an emergence many novel (or well‐overlooked old) chemotypes for drug discovery, which is related adapting new synthetic methodologies, designing sp 3 ‐enriched bioisosteres, paying attention previously underrated even unwanted) structural motifs, or combination thereof. In this review with 532 references, a survey selected that emerged recently in provided, focus synthesis corresponding blocks. Thus, saturated (hetero)aliphatic boronates, sulfonyl fluorides, sulfinates, non‐classical benzene isosteres, bicyclic morpholine/piperidine/piperazine analogs, as well gem ‐difluorinated cycloalkanes (as example emerging fluorinated motifs) are discussed.

Язык: Английский

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Radical Carbonyl Umpolung Arylation via Dual Nickel Catalysis

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(4), С. 1899 - 1909

Опубликована: Янв. 18, 2022

The formation of carbon-carbon bonds lies at the heart synthetic organic chemistry and is widely applied to construct complex drugs, polymers, materials. Despite its importance, catalytic carbonyl arylation remains comparatively underdeveloped, due limited scope functional group tolerance. Herein we disclose an umpolung strategy achieve radical via dual catalysis. This redox-neutral approach provides a complementary method Grignard-type products from (hetero)aryl bromides aliphatic aldehydes, without need for pre-functionalization. A sequential activation, hydrogen-atom transfer, halogen atom transfer process could directly convert aldehydes corresponding ketyl-type radicals, which further react with aryl-nickel intermediates in overall polarity-reversal process. tolerates─among others─acidic groups, heteroaryl motifs, sterically hindered substrates has been late-stage modification drugs natural products.

Язык: Английский

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Visible-Light Copper Nanocluster Catalysis for the C–N Coupling of Aryl Chlorides at Room Temperature

Journal of the American Chemical Society, Год журнала: 2022, Номер 144(27), С. 12052 - 12061

Опубликована: Июнь 29, 2022

Activation of aryl chlorides in cross-coupling reactions is a long-standing challenge organic synthesis that great interest to industry. Ultrasmall (<3 nm), atomically precise nanoclusters (NCs) are considered one the most promising catalysts due their high surface area and unsaturated active sites. Herein, we introduce copper nanocluster-based catalyst, [Cu61(StBu)26S6Cl6H14] (Cu61NC) enables C–N bond-forming under visible-light irradiation at room temperature. A range N-heterocyclic nucleophiles electronically sterically diverse aryl/hetero react this new Cu61NC-catalyzed process afford coupling products good yields. Mechanistic studies indicate single-electron-transfer (SET) between photoexcited Cu61NC complex halide C–N-arylation reaction.

Язык: Английский

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