Single-Atom Fe-Catalyzed Acceptorless Dehydrogenative Coupling to Quinolines

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(33), P. 23338 - 23347

Published: Aug. 6, 2024

A single-atom iron catalyst was found to exhibit exceptional reactivity in acceptorless dehydrogenative coupling for quinoline synthesis, outperforming known homogeneous and nanocatalyst systems. Detailed characterizations, including aberration-corrected HAADF-STEM, XANES, EXAFS, jointly confirmed the presence of atomically dispersed centers. Various functionalized quinolines were efficiently synthesized from different amino alcohols a range ketones or alcohols. The achieved turnover number (TON) up 10

Language: Английский

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NNN manganese complex-catalyzed α-alkylation of methyl ketones using alcohols: an experimental and computational study

Dalton Transactions, Journal Year: 2024, Volume and Issue: 53(7), P. 3236 - 3243

Published: Jan. 1, 2024

A quinoline-based pincer Mn catalyst for α-alkylation of methyl ketones using primary alcohols as alkyl surrogates is presented. The C–C bond formation reaction proceeds via a hydrogen auto-transfer protocol, generating water the only by-product.

Language: Английский

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Iron- and Organo-Catalyzed Borrowing Hydrogen for the Stereoselective Construction of Tetrahydropyrans

Organic Letters, Journal Year: 2024, Volume and Issue: 26(27), P. 5788 - 5793

Published: June 27, 2024

Stereocontrolled oxa-Michael additions are challenging, given the high reversibility of process, which ultimately leads to racemization newly formed stereocenters. When iron-catalyzed borrowing hydrogen from allylic alcohols was combined with a stereocontrolled organocatalytic addition, wide array chiral tetrahydropyrans were efficiently prepared. The reaction could be performed in diastereoselective manner pre-existing stereocenters or enantioselectively achiral substrates. key success reactivity iron complex, selective for alcohol dehydrogenation and irreversibly led final product.

Language: Английский

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CO to Isonitrile Substitution in Iron Cyclopentadienone Complexes: A Class of Active Iron Catalysts for Borrowing Hydrogen Strategies

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(10), P. 7795 - 7805

Published: May 6, 2024

Discovering active, cheap iron complexes for eco-compatible borrowing hydrogen transformations constitutes a real challenge. In this context, we developed family of isonitrile-substituted cyclopentadienone complexes. They were successfully applied in traditional amine alkylation with alcohols and, notably, the development photoactivated multicatalytic enantioselective allylic alcohol functionalization. Of importance, catalyst showing greater activity under photoirradiation differs from one most active conventional using chemical activation. This underscores importance incorporating isonitrile ligands readily customizable manner, resulting catalysts complementary reactivities. The characterization their physical properties was complemented by density functional theory calculations to enhance our understanding behavior. Given distinctive disclosed catalysts, application is poised pave way exploring challenging reactivities related catalytic processes.

Language: Английский

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Change in the Product Selectivity in the Visible Light-Induced Selenium Radical-Mediated 1,4-Aryl Migration Process

Organic Letters, Journal Year: 2022, Volume and Issue: 24(44), P. 8180 - 8185

Published: Oct. 28, 2022

Herein, we demonstrate a visible light-induced selenium radical-mediated domino reaction of aryl alkynoates, for the synthesis 1,1-diselenide alkene derivatives and selenium-containing α,β-unsaturated carboxylic acid. The process is mild, metal free, easy to handle, scalable. decarboxylation step can be controlled by applying catalytic amount Eosin Y dye cesium carbonate as base. methodology shows good functional group tolerance provides decent yields products. In addition, synthetic utility this protocol was expanded further preparing allylic alcohol, ester, vinylic halides.

Language: Английский

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Recent Development of Photoinduced Iron-Catalysis in Organic Synthesis

Chinese Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 43(4), P. 1386 - 1386

Published: Jan. 1, 2023

In recent years, the development and application of transition metal ruthenium or iridium complexes based photocatalysts have opened up a new research field for organic synthesis, which provides mild efficient strategies construction chemical bonds transformations.In order to enrich types photocatalysts, broaden scope photocatalysis, develop green sustainable chemistry, some low-cost easily available organometallic with copper iron were applied as recently.Iron-complexes feature non-toxicity, rich variety, unique property charge transfer from ligands metals, enable them show extraordinary capability in photocatalytic synthesis.According different reaction types, this review focuses on photoinduced iron-catalysis synthesis including C-H bond functionalization, C-C bifunctionalization alkenes, cross-coupling reaction, decarboxylative selective oxidation reduction.

Language: Английский

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Enantioselective Alkylation of Glycine Imines Using a Cinchona-Functionalized Crown Ether-Strapped Calixarene Phase-Transfer Catalyst

The Journal of Organic Chemistry, Journal Year: 2023, Volume and Issue: 88(11), P. 7498 - 7503

Published: May 23, 2023

We report a class of quaternary ammonium Cinchona-functionalized crown ether-strapped calix[4]arene phase-transfer catalysts for the efficient enantioselective α-alkylation glycine imines. The catalyst exhibits excellent catalytic performance at 0.1 mol % loading, affording desired α-alkylated glycinates with 98% yield and 99.9% ee. could be recovered recycled up to 30 test cycles without significant drop in activity.

Language: Английский

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Enhancement of Knölker Iron Catalysts for Imine Hydrogenation by Predictive Catalysis: From Calculations to Selective Experiments

Organometallics, Journal Year: 2023, Volume and Issue: 42(14), P. 1784 - 1792

Published: June 1, 2023

The reductive amination reaction of imines catalyzed by Knölker-type iron complexes under hydrogen at high pressure is very interesting in synthetic terms. This type an important catalytic challenge, since harsh conditions are necessary and do not occur easily. In a previous work ( Organometallics 2022, 41, 1204−1215), we carried out computational study the mechanism showing that electron-withdrawing groups (EWGs) attached to cyclopentadienone favor imines. synthesis with cyclopentadienones having EWGs straightforward, direct bonding on would lead but undesired dimerization. A possible solution consists addition phenyl substituents these catalysts then introduction rings. We have performed studies using density functional theory (DFT) for analyze efficiency such approach. found some facilitate result has been later confirmed experimentally, therefore, computationally designed new improve performances previously known complexes.

Language: Английский

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Functional group tolerant hydrogen borrowing C-alkylation

Nature Communications, Journal Year: 2024, Volume and Issue: 15(1)

Published: June 15, 2024

Abstract Hydrogen borrowing is an attractive and sustainable strategy for carbon–carbon bond formation that enables alcohols to be used as alkylating reagents in place of alkyl halides. However, despite intensive efforts, limited functional group tolerance observed this methodology, which we hypothesize due the high temperatures harsh basic conditions often employed. Here demonstrate room temperature tolerant hydrogen can achieved with a simple iridium catalyst presence substoichiometric base without excess reagents. Achieving yields necessitates application anaerobic counteract oxygen sensitivity catalytic hydride intermediate, otherwise leads degradation. Substrates containing heteroatoms capable complexing exhibit reactivity, but moderately higher extension broad range medicinally relevant nitrogen rich heterocycles. These newly developed allow possessing groups were previously incompatible reactions

Language: Английский

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Selective Monoalkylation or Dialkylation of Indenes with Alcohols by Bis-N-Heterocyclic Carbene Manganese

ACS Catalysis, Journal Year: 2024, Volume and Issue: unknown, P. 18032 - 18044

Published: Nov. 22, 2024

Selective direct alkylation of indenes is important for the synthesis and decoration indene derivatives. In contrast to traditional methods, using unactivated alcohol as reagents via borrowing hydrogen or autotransfer highly attractive. However, nature high-lying lowest unoccupied molecular orbital condensation intermediate raises a big challenge development BH system alcohols. Through tuning stability reactivity metal-hydride species by theoretical prediction, herein, we succeeded in developing non-noble Mn-catalyzed selective monoalkylation dialkylation under mild conditions, producing corresponding versatile alkylated satisfactory yields. A broad scope substrates including primary benzylic, aliphatic, amino, hydroxyl, second alcohols well various are tolerated system. Additionally, this method could be used potential precatalyst complexes bioactive molecules. Mechanistic studies control experiments, kinetic investigations, isotope effect, deuterium labeling density functional theory calculations, reveal proper successful process.

Language: Английский

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