Progress in organocatalysis with hypervalent iodine catalysts

Chemical Society Reviews, Год журнала: 2022, Номер 51(18), С. 8102 - 8139

Опубликована: Янв. 1, 2022

Hypervalent iodine compounds as environmentally friendly and relatively inexpensive reagents have properties similar to transition metals. They are employed alternatives metal catalysts in organic synthesis mild, nontoxic, selective recyclable catalytic reagents. Formation of C-N, C-O, C-S, C-F C-C bonds can be seamlessly accomplished by hypervalent catalysed oxidative functionalisations. The aim this review is highlight recent developments the utilisation iodine(III) iodine(V) a wide range including chiral for stereoselective synthesis. Polymer-, magnetic nanoparticle- framework-supported also described.

Язык: Английский

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Recent Progress in Synthetic Applications of Hypervalent Iodine(III) Reagents

Chemical Reviews, Год журнала: 2024, Номер unknown

Опубликована: Сен. 13, 2024

Hypervalent iodine(III) compounds have found wide application in modern organic chemistry as environmentally friendly reagents and catalysts. iodine are commonly used synthetically important halogenations, oxidations, aminations, heterocyclizations, various oxidative functionalizations of substrates. Iodonium salts arylating reagents, while iodonium ylides imides excellent carbene nitrene precursors. Various derivatives benziodoxoles, such azidobenziodoxoles, trifluoromethylbenziodoxoles, alkynylbenziodoxoles, alkenylbenziodoxoles group transfer the presence transition metal catalysts, under metal-free conditions, or using photocatalysts photoirradiation conditions. Development hypervalent catalytic systems discovery highly enantioselective reactions chiral represent a particularly recent achievement field chemistry. Chemical transformations promoted by many cases unique cannot be performed any other common, non-iodine-based reagent. This review covers literature published mainly last 7-8 years, between 2016 2024.

Язык: Английский

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Stereodivergent Synthesis of the Vicinal Difluorinated Tetralin of Casdatifan Enabled by Ru-Catalyzed Transfer Hydrogenation

Organic Letters, Год журнала: 2025, Номер unknown

Опубликована: Янв. 13, 2025

We disclose a stereodivergent strategy to prepare vicinal difluorinated tetralins from γ-substituted tetralones via combination of catalyst-controlled transfer hydrogenation and substrate-controlled fluorinations. This process is easily scalable amenable highly functionalized substrates, as demonstrated here in the late-stage synthesis casdatifan, clinical-stage inhibitor hypoxia-inducible factor-2α. Analysis physicochemical properties which features cis-vicinal difluoride, revealed higher level facial polarization compared its trans-vicinal difluoride isomers.

Язык: Английский

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Stereocontrolled Synthesis of Fluorinated Isochromans via Iodine(I)/Iodine(III) Catalysis

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(30)

Опубликована: Май 10, 2022

The success of saturated, fluorinated heterocycles in contemporary drug discovery provides a stimulus for creative endeavor main group catalysis. Motivated by the ubiquity isochromans across bioactive small molecule spectrum, prominence anomeric effect regulating conformation, and metabolic lability benzylic position, iodine(I)/iodine(III) catalysis has been leveraged stereocontrolled generation selectively analogs. To augment current arsenal fluorocyclization reactions involving carboxylic acid derivatives, reaction readily accessible 2-vinyl benzaldehydes is disclosed (up to >95 : 05 d.r. 97 03 e.r.). Key stereoelectronic interactions manifest themselves X-ray crystal structures products, thereby validating [CH

Язык: Английский

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Catalyst-Substrate Helical Character Matching Determines the Enantioselectivity in the Ishihara-Type Iodoarenes Catalyzed Asymmetric Kita-Dearomative Spirolactonization

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(13), С. 7301 - 7312

Опубликована: Март 20, 2023

Catalyst design has traditionally focused on rigid structural elements to prevent conformational flexibility. Ishihara's elegant of conformationally flexible C2-symmetric iodoarenes, a new class privileged organocatalysts, for the catalytic asymmetric dearomatization (CADA) naphthols is notable exception. Despite widespread use Ishihara catalysts CADAs, reaction mechanism remains subject debate, and mode induction not been well established. Here, we report an in-depth computational investigation three possible mechanisms in literature. Our results, however, reveal that this best rationalized by fourth called "proton-transfer-coupled-dearomatization (PTCD)", which predicted be strongly favored over other competing pathways. The PTCD consistent with control experiment further validated applying it rationalize enantioselectivities. Oxidation I(I) catalyst active I(III) species induces defined helical chiral environment delicate balance between flexibility rigidity. A match/mismatch effect substrate's shape transition states was observed. match allows adapt its conformation maximize attractive noncovalent interactions, including I(III)···O halogen bond, N-H···O hydrogen π···π stacking, stabilize state. stereochemical model capable rationalizing variation enantioselectivities developed. present study enriches our understanding how achieve high stereoinduction may serve as inspiration future exploration designs.

Язык: Английский

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Recent Advancement on Selectfluor Mediated Synthesis of Heterocyclic Molecules

The Chemical Record, Год журнала: 2025, Номер unknown

Опубликована: Янв. 16, 2025

Abstract Selectfluor, [1‐chloromethyl‐4‐fluoro‐1,4‐diazoniabicyclo[2.2.2]octane bis(tetrafluoroborate)], is a highly valuable reagent in contemporary chemistry, serving not only as an electrophilic fluorinating agent but also effective catalyst the synthesis of various pharmaceutically relevant heterocycles. This review article seeks to present comprehensive overview significant heterocyclic ring formations facilitated by selectfluor. Both metal‐free and metal‐catalyzed recent advancement on selectfluor mediated cyclisation processes are discussed this mainly over last eight years (2017‐April 2024).

Язык: Английский

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Recent Advances in Catalytic Asymmetric Syntheses of Functionalized Heterocycles via Halogenation/Chalcogenation of Carbon‐Carbon Unsaturated Bonds

Advanced Synthesis & Catalysis, Год журнала: 2022, Номер 364(23), С. 3974 - 4005

Опубликована: Окт. 20, 2022

Abstract Halogen (fluorine, chlorine, bromine, iodine) or chalcogen (sulfur, selenium)‐containing heterocycles are widely recognized as key building blocks in many natural products and bioactive targets. Catalytic asymmetric halogenation/chalcogenation of carbon‐carbon unsaturated bonds via onium ion transformations efficient methods to obtain diverse chiral heterocyclic backbones. In the past few years, catalytic enantioselective versions halo/thio/seleno‐functionalizations with various halogen electrophiles have experienced constant development. This review highlights those advances preparing functionalized promoted by organocatalysts metal‐based catalysts. magnified image

Язык: Английский

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Diverting the 5-exo-Trig Oxypalladation to Formally 6-endo-Trig Fluorocycloetherification Product through 1,2-O/Pd(IV) Dyotropic Rearrangement

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(29), С. 15735 - 15741

Опубликована: Июль 18, 2023

Pd-catalyzed cyclizative functionalization of γ-hydroxyalkenes affords tetrahydrofuran derivatives via a key 5-exo-trig oxypalladation step. Herein, we report palladium(II)-catalyzed, Selectfluor-mediated formal 6-endo-trig fluorocycloetherification for the synthesis functionalized tetrahydropyrans. Mechanistically, an σ-alkyl-Pd(II) intermediate resulting from process is isolated and characterized by X-ray crystallographic analysis. Its oxidation with Selectfluor to Pd(IV) triggers chemoselective 1,2-O/Pd(IV) dyotropic rearrangement affording, after C-F bond-forming reductive elimination, tetrahydropyrans concurrent generation tertiary carbon-fluorine bond. The occurrence this 1,2-positional interchange further evidenced trapping rearranged quaternary C(sp3)-Pd bond internal nucleophile that materialized development Pd(II)-catalyzed oxidative bis-heterocyclization alkenes.

Язык: Английский

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Apparent 6‐endo‐trig Carbofluorination of Alkenes Enabled by Palladium‐Based Dyotropic Rearrangement

Angewandte Chemie International Edition, Год журнала: 2022, Номер 61(50)

Опубликована: Окт. 12, 2022

Alkene difunctionalization featuring an intramolecular carbometallation step has been developed into a powerful transformation in organic synthesis. The 5-exo-trig is general highly favored over the alternative 6-endo-trig cyclization. We report herein formal carbofluorination protocol by combining conventional carbopalladation with chemoselective 1,2-aryl/Pd dyotropic rearrangement. Treatment of 2-(2-alkylallyloxy)phenyl boronic acid derivatives presence catalytic amount Pd(dba)2 , 4,4'-di-tert-butyl-2,2'-bipyridine and Selectfluor affords chromanes concurrent generation tertiary alkyl fluoride function. A σ-alkyl-PdII species resulting from process isolated characterized X-ray crystallographic analysis. Its oxidation to PdIV complex triggers rearrangement leading ring expansion product.

Язык: Английский

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Rhodium‐Catalyzed Hydrosilylation of Alkenes with Acylhydrosilanes

Chemistry - A European Journal, Год журнала: 2023, Номер 29(40)

Опубликована: Апрель 12, 2023

Acylsilanes are an important class of organosilicon compounds that have gained increased attention recently. Their various reaction modes in particularly their ability to generate carbenes under thermal or photochemical conditions render them valuable reagents organic synthesis. In this communication, unprecedented route towards acylsilanes is reported by introducing the acylsilane moiety directly a single step through alkene hydrosilylation. context, acylhydrosilanes representing novel introduced and applied as silylation rhodium catalyzed hydrosilylations access great variety acylsilanes. These reactions occur good excellent yields mild show high functional group tolerance atom economy.

Язык: Английский

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