Synthesis of Diverse 4‐Pyrrolin‐2‐ones by Electrochemically Induced Dehydrogenative Regioselective Cyclization of 3‐Aza‐1,5‐dienes and 1,3‐Dicarbonyl Compounds

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(11)

Опубликована: Янв. 20, 2024

Abstract A practical and mild electrochemical dehydrogenative regioselective cyclization method has been established for the synthesis of 4‐pyrrolin‐2‐ones using 3‐aza‐1,5‐dienes 1,3‐dicarbonyl compounds as substrates. This protocol is catalyst‐free, metal‐free, does not require oxidizing agents. It exhibits wide substrate compatibility can be easily scaled up to gram scale.

Язык: Английский

---

Redox Approaches to Carbene Generation in Catalytic Cyclopropanation Reactions

Angewandte Chemie International Edition, Год журнала: 2024, Номер 63(29)

Опубликована: Май 16, 2024

Abstract Transition metal‐catalyzed carbene transfer reactions have a century‐old history in organic chemistry and are primary method for the synthesis of cyclopropanes. Much work this field has focused on use diazo compounds related precursors, which can fragment to catalyst with concomitant loss stable byproduct. Despite utility approach, there persistent limitations scope viable carbenes, most notably those lacking stabilizing substituents. By coupling two‐electron redox cycles, it is possible expand available starting materials that be used as precursors. In Minireview, we discuss emerging catalytic reductive cyclopropanation using either gem ‐dihaloalkanes or carbonyl compounds. This strategy inspired by classic stoichiometric transformations, such Simmons–Smith Clemmensen reduction, but instead entails formation catalytically generated transition metal carbenoid. We also present recent efforts generate carbenes directly from methylene (CR 2 H ) groups via formal 1,1‐dehydrogenation. These currently restricted substrates containing electron‐withdrawing substituents, serve facilitate deprotonation subsequent oxidation anion.

Язык: Английский

---

A water-soluble type II photosensitizer for selective photooxidation reactions of hydroazaobenzenes, olefins, and hydrosilanes in water

Green Chemistry, Год журнала: 2024, Номер 26(4), С. 2241 - 2247

Опубликована: Янв. 1, 2024

A water-soluble type II photosensitizer with excellent water solubility was utilized for selective photooxidation reactions of hydroazaobenzenes, olefins, and hydrosilanes in water.

Язык: Английский

---

Synergistic Brønsted Base/Photoredox‐Catalyzed Three‐Component Coupling with Malonates to Synthesize δ‐Hydroxy Esters and δ‐Keto Esters

Chinese Journal of Chemistry, Год журнала: 2024, Номер 42(9), С. 957 - 962

Опубликована: Янв. 18, 2024

Comprehensive Summary Multicomponent alkene 1,2‐dicarbofunctionalizations (DCFs) have emerged as a powerful strategy to rapidly incorporate both two carbon subunits across one C—C double bond in step for enhancing molecular complexity and diversity. To the best of our knowledge, there is only report on photoredox‐catalyzed three‐component DCFs with malonates through radical−radical cross‐coupling, while radical‐polar crossover (RPC)‐type were still rare. Herein, we describe redox‐neutral RPC‐type 1,2‐dialkylation styrenes aldehydes synergistic Brønsted base/photoredox catalysis system. This transition‐metal‐free provides an efficient clean approach broad variety δ‐hydroxy esters also features exceptionally mild conditions, wide compatibility substrate scope functional groups, high atomic economy. Moreover, 1,2‐alkylacylation from same starting materials was achieved one‐pot manner such coupling subsequent two‐electron oxidation process, providing set δ‐keto interest pharmaceutical research.

Язык: Английский

---

Cyano migration-mediated radical-polar crossover cyclopropanation

Science China Chemistry, Год журнала: 2024, Номер unknown

Опубликована: Сен. 3, 2024

---

The efficient synthesis of three-membered rings via photo- and electrochemical strategies

Chemical Science, Год журнала: 2024, Номер 15(34), С. 13576 - 13604

Опубликована: Янв. 1, 2024

Three-membered rings, such as epoxides, aziridines, oxaziridines, cyclopropenes, vinyloxaziridines, and azirines, are recognized crucial pharmacophores building blocks in organic chemistry drug discovery. Despite the significant advances synthesis of these rings through photo/electrochemical methods over past decade, there has currently been no focused discussion updated overviews on this topic. Therefore, we presented review article efficient three-membered using photo- electrochemical strategies, covering literature since 2015. In study, a conceptual overview detailed discussions were provided to illustrate advancement field. Moreover, brief outlines current challenges opportunities synthesizing strategies.

Язык: Английский

---

Anti-selective Cyclopropanation of Nonconjugated Alkenes with Diverse Pronucleophiles via Directed Nucleopalladation

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(35), С. 24503 - 24514

Опубликована: Авг. 22, 2024

A facile approach to obtaining densely functionalized cyclopropanes is described. The reaction proceeds under mild conditions via the directed nucleopalladation of nonconjugated alkenes with readily available pronucleophiles and gives excellent yields good anti-selectivity using I2 TBHP as oxidants. Pronucleophiles bearing a diverse collection electron-withdrawing groups, including −CN, −CO2R, −COR, −SO2Ph, −CONHR, −NO2, are well tolerated. Internal alkenes, which generally challenging substrates in other cyclopropanation methods, provide diastereoselectivity this methodology, allowing for controlled access substituted at all three C atoms. DFT calculations mechanistic experiments reveal that major pathway involves initial α-iodination nucleophile, followed by anti-carbopalladation intramolecular C(sp3)–I oxidative addition. Strain-release-promoted C(sp3)–C(sp3) reductive elimination then furnishes cyclopropanated product.

Язык: Английский

---

Transient‐State Self‐Bipolarized Organic Frameworks of Single Aromatic Units for Natural Sunlight‐Driven Photosynthesis of H₂O₂

Advanced Science, Год журнала: 2024, Номер 11(24)

Опубликована: Март 17, 2024

Abstract Constructing π‐conjugated polymer structures through covalent bonds dominates the design of organic framework photocatalysts, which significantly depends on selection multiple donor‐acceptor building blocks to narrow optical gap and increase lifetimes charge carriers. In this work, self‐bipolarized frameworks single aromatic units are demonstrated as novel broad‐spectrum‐responsive photocatalysts for H 2 O production. The preparation such is only fix (such 1,3,5‐triphenylbenzene) with alkane linkers in 3D space. Self‐bipolarized can drive production from under natural sunlight, wide pH ranges (3.0‐10.0) water sources. Moreover, it be extended catalyze oxidative coupling amines. Experimental theoretical investigation demonstrate that a strategy obeys mechanism through‐space π‐conjugation, where closely face‐to‐face overlapped rings permit electron energy transfer large‐area delocalization cloud visible light irradiation. This work introduces concept development will break restriction conventional through‐band π‐conjugation structure open new way synthesis photocatalysts.

Язык: Английский

---

Distinct Photochemistry of Odd-Carbon PAHs from the Even-Carbon Ones During the Photoaging and Analysis of Soot

Environmental Science & Technology, Год журнала: 2024, Номер 58(26), С. 11578 - 11586

Опубликована: Июнь 20, 2024

Polycyclic aromatic hydrocarbons (PAHs) are the primary organic carbons in soot. In addition to PAHs with even carbon numbers (PAH

Язык: Английский

---

Fundamentals of metal-organic framework-based photocatalysts: The role of chemical diversity and structure engineering

Coordination Chemistry Reviews, Год журнала: 2024, Номер 525, С. 216324 - 216324

Опубликована: Ноя. 24, 2024

Язык: Английский

---