Recent Advances in Dearomative Partial Reduction of Benzenoid Arenes

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(21)

Опубликована: Март 14, 2024

Abstract Dearomative partial reduction is an extraordinary approach for transforming benzenoid arenes and has been well‐known many decades, as exemplified by the dehydrogenation of Birch hydroarylation Crich addition. Despite its remarkable importance in synthesis, this field experienced slow progress over last half‐century. However, a revival observed with recent introduction electrochemical photochemical methods. In Minireview, we summarize advancements dearomative arenes, including dihydrogenation, hydroalkylation, arylation, alkenylation, amination, borylation others. Further, intriguing utilization synthesis natural products also emphasized. It anticipated that Minireview will stimulate further arene transformations.

Язык: Английский

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Chemoselective 1,2‐Reduction and Regiodivergent Deuteration of Chromium‐Bound Arenes

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(18)

Опубликована: Фев. 23, 2023

Herein, a general strategy for chemo- and regioselective 1,2-reduction of chromium-bound arenes was developed, thus providing rapid access to 1,3-cyclohexadienes. Selective arene activation via π-complexation along with the use mild hydride Ph3 SiH can overcome inherently low reactivity π-bonds while tolerating various reduction-sensitive functional groups. Its versatility further enables regiodivergent deuteration. Using different sequences (non)deuterated acid reagents, deuterated positions as well degrees deuterium incorporation be controlled precisely, which leads large previously inaccessible chemical space 1,3-cyclohexadiene isotopologues. A reasonable mechanism proposed based on intermediate capture control experiments. The synthetic value this selective demonstrated in formal total synthesis (±)-galanthamine (±)-lycoramine.

Язык: Английский

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Chemoselective Quinoline and Isoquinoline Reduction by Energy Transfer Catalysis Enabled Hydrogen Atom Transfer

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(48)

Опубликована: Окт. 7, 2023

(Hetero)arene reduction is one of the key avenues for synthesizing related cyclic alkenes and alkanes. While catalytic hydrogenation Birch are two broadly utilized approaches (hetero)arene across academia industry over last century, both methods have encountered significant chemoselectivity challenges. We hereby introduce a highly chemoselective quinoline isoquinoline protocol operating through selective energy transfer (EnT) catalysis, which enables subsequent hydrogen atom (HAT). The design this bypasses conventional metric reaction, that is, reductive potential, instead relies on triplet energies chemical moieties kinetic barriers events. Many reducing labile functional groups, were incompatible with previous reactions, retained in reaction. anticipate will trigger further advancement arene enable current arene-rich drug space to escape from flatland.

Язык: Английский

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Umpolung‐Enabled Divergent Dearomative Carbonylations

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(33)

Опубликована: Май 31, 2024

Although dearomative functionalizations enable the direct conversion of flat aromatics into precious three-dimensional architectures, case for simple arenes remains largely underdeveloped owing to high aromatic stabilization energy. We herein report a sequential addition two nucleophiles arene π-bonds through umpolung chromium-arene complexes. This mode enables divergent carbonylation reactions benzene derivatives by tolerating various in combination with alcohols or amines under CO-gas-free conditions, thus providing modular access functionalized esters amides. The tunable synthesis 1,3- 1,4-cyclohexadienes as well construction carbon quaternary centers further highlight versatility this dearomatization. Diverse late-stage modifications and derivatizations towards synthetically challenging bioactive molecules reveal synthetic utility. A possible mechanism was proposed based on control experiments intermediate tracking.

Язык: Английский

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Intermolecular Dearomative 1,2‐Amination/Carbonylation via Nucleophilic Addition of Simple Amines to Arene π‐Bonds

Chemistry - A European Journal, Год журнала: 2023, Номер 29(36)

Опубликована: Апрель 19, 2023

The incorporation of the privileged amino functionality is paramount importance in organic synthesis. In contrast to well-developed amination methods for alkenes, dearomative arenes largely underexplored due inherently inert reactivity arene π-bonds and selectivity challenges. Herein, we report an intermolecular aminofunctionalization via direct nucleophilic addition simple amines chromium-bound arenes. This multicomponent 1,2-amination/carbonylation reaction enables rapid access complicated alicyclic compounds containing amide functionalities from benzene derivatives under CO-gas-free conditions, which also represents first application nitrogen-based nucleophiles η6 -coordination-induced dearomatizations.

Язык: Английский

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Multicomponent Tf₂O-Triggered Dearomative Triazinylmethylation of Isoquinolines Using Acetonitrile

The Journal of Organic Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Фев. 13, 2025

A Tf2O-triggered dearomative triazinylmethylation of isoquinolines and other azaarenes utilizing acetonitrile as the nucleophile has been developed through a formal five-component reaction. This method showcases broad substrate scope exceptional functional group compatibility, presenting mild expedient synthetic approach. Kinetic studies, including kinetic isotope effect (KIE) Hammett analysis, indicate that activation by Tf2O constitutes rate-limiting step.

Язык: Английский

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Copper‐Functionalized MIL‐101(Cr): An Efficient, Reusable, and Heterogeneous Catalyst for Chan–Lam Coupling and Amide Bond Formation

ChemistrySelect, Год журнала: 2025, Номер 10(11)

Опубликована: Март 1, 2025

Abstract Efficient protocols for the synthesis of secondary amines using phenylboronic acid and aniline via Chan–Evan–Lam coupling reaction amides by oxidative amidation aldehydes with utilizing heterogeneous, recyclable MIL‐101(Cr)‐SB‐Cu catalyst have been developed. has synthesized post‐synthetic modification amino‐functionalized MIL‐101(Cr). Various spectroscopic analytical methods, such as FT‐IR, PXRD, SEM, TEM, EDX, XPS, ICP‐OES, TG were used to characterize catalyst. The showed excellent catalytic activity provided good yields desired products under mild conditions. can be reused up five consecutive runs without significant loss in its activity. Low loading, easy work‐up, gram‐scale synthesis, a simple preparation are some other advantages this approach.

Язык: Английский

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Extensive Studies on the Synthesis and Characterization of π‐Arene Chromium Complexes and Their Performance in S_NAr and Suzuki–Miyaura Cross‐Coupling Reactions

Chemistry - An Asian Journal, Год журнала: 2025, Номер unknown

Опубликована: Апрель 25, 2025

Abstract We report an efficient synthesis of a series new (η 6 ‐arene)Cr(CO) 3 complexes via ligand exchange strategy under thermal conditions using chromium hexacarbonyl and readily accessible arene feedstocks. optimized the previously reported procedures found that high excess arenes usually employed is not required to access π ‐arene in yields. Consequently, revised procedure simplifies purification tricarbonyl bearing with boiling points. The reaction amenable provide decorated various functional groups. Notably, novel already missing spectroscopic characterization were fully characterized by nuclear magnetic resonance (NMR), infrared (IR) spectroscopies, high‐resolution mass spectrometry (HRMS). Besides, we structure 20 X‐ray crystallography. potential application these has also been exploited toward selective construction poly(hetero)aryls possessing single unit through S N Ar Suzuki–Miyaura cross‐coupling reactions. This work meant be practical guide for fill gap their characterization.

Язык: Английский

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Chromium(II)-Catalyzed Defluorinative Reductive Cross-Coupling of Acetals with α-Trifluoromethyl Alkenes

Organic & Biomolecular Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

α-Alkoxyalkyl radicals are generated from acetals by chromium catalysis. The addition of the to α-trifluoromethyl alkenes, followed β-fluoride elimination, efficiently produces gem -difluoroalkenes with a homoallylic alkoxy group.

Язык: Английский

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Radical‐Dearomative Generation of Cyclohexadienyl Pd(II) toward the 3D Transformation of Nonactivated Phenyl Rings

Advanced Science, Год журнала: 2023, Номер 11(9)

Опубликована: Дек. 15, 2023

Abstract Traditional palladium‐catalyzed dearomatization of (hetero)arenes takes place via an ionic pathway and usually requires elevated temperatures to overcome the energy barrier dearomative insertion step. Herein, a combination radical two‐electron pathways is disclosed, which enables room temperature 3D transformations nonactivated phenyl rings with Pd(0) as catalyst. Experimental results together density functional theory (DFT) calculations indicate versatile π‐allyl Pd(II) species, cyclohexadienyl Pd(II), possibly involved in dearomatization. This species generated by combining Pd(I). The provides chemoselective (carboamination trieneylation), regioselective (1,2‐carboamination), diastereoselective (carbonyl‐group directed face selectivity) conversions.

Язык: Английский

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