Ligand-free Guerbet-type reactions in air catalyzed by in situ formed complexes of base metal salt cobaltous chloride

Catalysis Science & Technology, Journal Year: 2022, Volume and Issue: 12(4), P. 1100 - 1108

Published: Jan. 1, 2022

Inexpensive, earth-abundant & environmentally benign CoCl 2 efficiently catalyses the β-alkylation of alcohol in unprecedented yields (89%) turnovers (8900). Mechanistic studies are indicative situ generated homogeneous molecular Co catalysts.

Language: Английский

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Ruthenium‐Catalyzed Selective α‐Alkylation of β‐Naphthols using Primary Alcohols: Elucidating the Influence of Base and Water

Chemistry - A European Journal, Journal Year: 2023, Volume and Issue: 29(59)

Published: July 24, 2023

Abstract Functionalized arenes and arenols have diverse applications in chemical synthesis material chemistry. Selective functionalization of is a topic prime interest. In particular, direct alkylation using alcohols challenging task. this report, ruthenium pincer catalyzed α‐alkylation β‐naphthol primary as alkylating reagents reported. Notably, aryl heteroaryl methanols linear branched aliphatic underwent selective reactions, which water the only byproduct. catalytically derived α‐alkyl‐β‐naphthol products displayed high absorbance, emissive properties, quantum yields (up to 93.2 %). Dearomative bromination on demonstrated synthetic application. Mechanistic studies indicate that reaction involves an aldehyde intermediate. DFT support finding further reveal stoichiometric amount base required make aldol condensation well elementary steps for regeneration active species. situ‐generated molecule from plays important role catalyst.

Language: Английский

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Optical activity levels of metal centers controlling multi-mode emissions in low-dimensional hybrid metal halides for anti-counterfeiting and information encryption

Chemical Science, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 1, 2024

The optical activity levels of metal centers govern the multi-mode emissions by manipulating band alignments in hybrid halides.

Language: Английский

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Mechanism of nickel-catalyzed direct carbonyl-Heck coupling reaction: the crucial role of second-sphere interactions

Dalton Transactions, Journal Year: 2021, Volume and Issue: 50(7), P. 2654 - 2662

Published: Jan. 1, 2021

We present a detailed DFT mechanistic study on the first Ni-catalyzed direct carbonyl-Heck coupling of aryl triflates and aldehydes to afford ketones.

Language: Английский

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Iridium Complexes as Efficient Catalysts for Construction of α‐Substituted Ketones via Hydrogen Borrowing of Alcohols in Water

European Journal of Organic Chemistry, Journal Year: 2021, Volume and Issue: 2021(9), P. 1355 - 1364

Published: Feb. 6, 2021

Abstract Ketones are of great importance in synthesis, biology, and pharmaceuticals. This paper reports an iridium complexes‐catalyzed cross‐coupling alcohols via hydrogen borrowing, affording a series α ‐alkylated ketones high yield (86 %–95 %) chemoselectivities (>99 : 1). methodology has the advantages low catalyst loading (0.1 mol%) environmentally benign water as solvent. Studies have shown amount base impact on chemoselectivities. Meanwhile, deuteration experiments show plays important role accelerating reduction unsaturated intermediates. Remarkably, gram‐scale experiment demonstrates this iridium‐catalyzed potential application practical synthesis ketones.

Language: Английский

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Phosphine‐Free Pincer Ruthenium‐Catalyzed α‐Alkylation of Ketones with Secondary Alcohols to form β‐Branched Ketones

ChemCatChem, Journal Year: 2023, Volume and Issue: 15(14)

Published: May 26, 2023

Abstract Herein, an efficient and expedient method was developed for α‐alkylation of aromatic ketones with secondary alcohols to produce β ‐disubstituted using phosphine‐free pincer ruthenium complexes as the catalyst. Single α ‐alkylated ketone is produced in high yields even reactions where a mixture products possible. Interestingly, challenging substrates such unsubstituted nonhindered acetophenone compounds are effectively alkylated under reaction conditions. The scope can span verities aliphatic, cyclic, acyclic alcohols. Functionalization cholesterol molecule also possible Substitution on cyclohexyl ring afforded diastereoisomers, wherein major isomer found 1,4‐cis conformation ring. Origin cis stereoselectivity alkylation process explored by DFT calculation study. Mechanistic studies reveal that dehydrogenation follows proton shuttle‐type TS, involvement cross‐aldol condensation borrowing hydrogen catalysis. Notably, this selective, catalytic C−C bond forming proceeds low catalyst load, amount base air produces H 2 O only byproduct, making environmentally benign atom efficient.

Language: Английский

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Selective control of secondary alcohols upgrading using Ir-catalyzed cross-coupling strategy

Science China Chemistry, Journal Year: 2023, Volume and Issue: 67(3), P. 914 - 921

Published: Nov. 16, 2023

Language: Английский

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Reactions of Aldehydes and Ketones and Their Derivatives

Organic Reaction Mechanisms/Organic reaction mechanisms, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 45

Published: March 15, 2024

The gold-catalyzed cyclization of 2-alkynylarylaldehyde cyclic acetals leads to indanone derivatives in good-to-excellent yields. It is possible use photoimmobilized Ni clusters on a CdS photocatalyst give imines by the dehydrogenation amines under visible-light illumination. process suitable for primary and secondary amines. An intramolecular asymmetric reductive amination aminoketones leading chiral 1,4-diazepanes catalyzed an imine reductase enzyme has been reported, which proceeds with high enantioselectivity. Aryl acetic acid esters other active methylene compounds react nitrosoarenes diastereoselective formation ketonitrones using 2-t-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine catalyst at room temperature. Saturated aliphatic tricycles including function have cyclized van Leusen imidazole synthesis p-toluenesulfonyl-methyl isocyanide (TosMIC). N-(Tosylmethyl) formamide, decomposition product TosMIC, was further transformed into N-methyleneformamide basic conditions acts as reduce reaction times improve

Language: Английский

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An Overview of Ruthenium-Catalyzed Multicomponent Reactions

Current Organic Chemistry, Journal Year: 2022, Volume and Issue: 26(12), P. 1119 - 1148

Published: June 1, 2022

Abstract: In multicomponent reactions (MCRs), highly functionalized compounds can be formed through the reaction between three or more reactants in a one-pot manner. These provide products utilization of lesser amounts energy, time, and effort. MCRs also possess advantages like generation waste materials. Fewer resources are needed, high convergence etc. terms energy economy atom economy, superior to multistep synthesis. A wide range acquired by combining reagents variety ways thus, became popular various fields such as catalysis, pharmaceutical chemistry, material science, agrochemistry, fine chemistry so on. obey principles green because these approaches simple ecofriendly. MCR is an unrivalled synthetic technique has been used chemists at accelerating rate recent years. Ruthenium catalysts cheap comparison palladium rhodium, generally show activity. Ru possesses wide-ranging oxidation states due its 4d7 5s1 electronic configuration. Numerous organic catalyzed ruthenium, which utilized forming pharmaceuticals natural products, with biological importance. Minimum materials most ruthenium-catalyzed reactions; hence, ruthenium catalysis paves way environmentally benign protocols. had really big impact on synthesis years it now par relevance. The developments field highlighted this review, covering literature up 2021.

Language: Английский

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Ru‐Catalyzed CC Bond Formation Through Alcohol Dehydrogenative Coupling Strategy

Handbook of CH‐Functionalization, Journal Year: 2022, Volume and Issue: unknown, P. 1 - 69

Published: Nov. 29, 2022

Abstract Finding a greener and more sustainable alternative to the waste generating conventional protocols for synthesis of CC bonds is challenging goal in current chemical research. In this context, utilization alcohol dehydrogenative coupling strategy has gained significant importance as it uses bio‐mass derived alcohols reagent produces water by‐product. article, following borrowing hydrogen (BH) acceptorless (ADC) strategy, progress improvements Ru‐based catalytic systems using various bidentate tridentate ligands with diverse electronic steric compatibilities bond formation are summarized. Following these protocols, several alkylated ketones, alcohols, nitriles, amides, indoles was successfully executed. Utilizing development Ru‐catalyzed atom‐economical, sustainable, efficient becomes one essential tools organic chemistry synthesize numerous value‐added products.

Language: Английский

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