Iridium-catalyzed Transfer Hydrogenation for Construction of Quinolines from 2-Aminobenzyl Alcohols with Enones in Water

Herein, we describe a method for the synthesis of functionalized quinolines from 2-aminobenzyl alcohols with α, β-unsaturated ketones. This method exhibits various functional groups tolerance, high-efficiency, environmentally benign and can be performed on a gram scale. Control experiment suggests this transformation is accomplished by iridium complex-catalyzed transfer hydrogenation, which is then followed by the Friedländer cyclization. The results display the alkali is essential for the high selectivities of this catalytic system.

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Bis-NHC–Ag/Pd(OAc)2 Catalytic System Catalyzed Transfer Hydrogenation Reaction

Catalysts ◽

10.3390/catal11010008 ◽

2020 ◽

Vol 11 (1) ◽

pp. 8

Author(s):

Hui-Ju Chen ◽

Chien-Cheng Chiu ◽

Tsui Wang ◽

Dong-Sheng Lee ◽

Ta-Jung Lu

Keyword(s):

Functional Groups ◽

Catalytic System ◽

High Efficiency ◽

Aqueous Media ◽

Hydrogenation Reaction ◽

Transfer Hydrogenation ◽

Terminal Alkynes ◽

Wide Range ◽

Transfer Hydrogenation Reaction

The bis-NHC–Ag/Pd(OAc)2 catalytic system (NHC = N-heterocyclic carbene), a combination of bis-NHC–Ag complex and Pd(OAc)2, was found to be a smart catalyst in the Pd-catalyzed transfer hydrogenation of various functionalized arenes and internal/terminal alkynes. The catalytic system demonstrated high efficiency for the reduction of a wide range of various functional groups such as carbonyls, alkynes, olefins, and nitro groups in good to excellent yields and high chemoselectivity for the reduction of functional groups. In addition, the protocol was successfully exploited to stereoselectivity for the transformation of alkynes to alkenes in aqueous media under air. This methodology successfully provided an alternative useful protocol for reducing various functional groups and a simple operational protocol for transfer hydrogenation.

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Tandem hydrogenation and condensation of fluorinated α,β-unsaturated ketones with primary amines, catalyzed by nickel

Dalton Transactions ◽

10.1039/c5dt02366a ◽

2015 ◽

Vol 44 (35) ◽

pp. 15653-15663 ◽

Cited By ~ 6

Author(s):

Nahury Castellanos-Blanco ◽

Marcos Flores-Alamo ◽

Juventino J. García

Keyword(s):

Catalytic System ◽

Transfer Hydrogenation ◽

Primary Amines ◽

Unsaturated Ketones ◽

Phosphine Complexes ◽

Hydrogen Donors ◽

Nickel Phosphine

A simple homogeneous catalytic system based on nickel phosphine complexes has been developed for the transfer hydrogenation and condensation of α,β-unsaturated ketones to yield saturated ones and saturated imines using primary amines as hydrogen donors.

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Iridium-Catalyzed Transfer Hydrogenation of Ketones and Aldehydes Using Glucose as a Sustainable Hydrogen Donor

Catalysts ◽

10.3390/catal9060503 ◽

2019 ◽

Vol 9 (6) ◽

pp. 503 ◽

Cited By ~ 7

Author(s):

Masato Yoshida ◽

Ryota Hirahata ◽

Takayoshi Inoue ◽

Takuya Shimbayashi ◽

Ken-ichi Fujita

Keyword(s):

Catalytic System ◽

Carbonyl Compounds ◽

Hydrogen Donor ◽

Transfer Hydrogenation ◽

Environmentally Benign ◽

Iridium Catalyst ◽

Hydrogenation Reactions

A new catalytic system for transfer hydrogenation of carbonyl compounds using glucose as a hydrogen donor was developed. Various ketones and aldehydes were efficiently converted to corresponding alcohols with two equivalents of glucose in the presence of a small amount (0.1 to 1.0 mol%) of iridium catalyst that had a functional ligand. In this catalytic system, transfer hydrogenation reactions proceeded based on the cooperativity of iridium and a functional ligand. It should be noted that environmentally benign water could have been used as a solvent in the present catalytic system for the reduction of various carbonyl substrates. Furthermore, the reaction scope could be extended by using N,N-dimethylacetamide as a reaction solvent.

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Chemoselective Transfer Hydrogenation of α,β-Unsaturated Ketones Catalyzed by Iridium Complexes

SynOpen ◽

10.1055/s-0040-1706022 ◽

2021 ◽

Vol 05 (01) ◽

pp. 36-42

Author(s):

Renshi Luo ◽

Yanping Xia ◽

Lu Ouyang ◽

Jianhua Liao ◽

Xiao Yang

Keyword(s):

Formic Acid ◽

Functional Groups ◽

Organic Solvents ◽

Mixed Solvents ◽

Transfer Hydrogenation ◽

Scale Transformation ◽

Iridium Complexes ◽

Practical Application ◽

Unsaturated Ketones ◽

Electron Withdrawing Substituents

AbstractEfficient chemoselective transfer hydrogenation of the C=C bond of α,β-unsaturated ketones has been developed, using the iridium complexes containing pyridine-imidazolidinyl ligands as catalysts and formic acid as a hydrogen source. In comparison with organic solvents or H2O as solvent, the mixed solvents of H2O and MeOH are critical for a high catalytic chemoselective transformation. This chemoselective transfer hydrogenation can be carried out in air, which is operationally simple, allowing a wide variety of α,β-unsaturated substrates with different functional groups (electron-donating and electron-withdrawing substituents) leading to chemoselective transfer hydrogenation in excellent yields. The practical application of this protocol is demonstrated by a gram-scale transformation.

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Non-Enzymatic Desymmetrization Reactions in Aqueous Media

Symmetry ◽

10.3390/sym13040720 ◽

2021 ◽

Vol 13 (4) ◽

pp. 720

Author(s):

Satomi Niwayama

Keyword(s):

Natural Products ◽

Total Synthesis ◽

Functional Groups ◽

Organic Compounds ◽

Recent Progress ◽

Aqueous Media ◽

Building Blocks ◽

Organic Reactions ◽

Environmentally Benign ◽

Enzymatic Desymmetrization

Symmetric organic compounds are generally obtained inexpensively, and therefore they can be attractive building blocks for the total synthesis of various pharmaceuticals and natural products. The drawback is that discriminating the identical functional groups in the symmetric compounds is difficult. Water is the most environmentally benign and inexpensive solvent. However, successful organic reactions in water are rather limited due to the hydrophobicity of organic compounds in general. Therefore, desymmetrization reactions in aqueous media are expected to offer versatile strategies for the synthesis of a variety of significant organic compounds. This review focuses on the recent progress of desymmetrization reactions of symmetric organic compounds in aqueous media without utilizing enzymes.

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Kinetic resolution of indolines by asymmetric hydroxylamine formation

Nature Communications ◽

10.1038/s41467-021-22658-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Gang Wang ◽

Ran Lu ◽

Chuangchuang He ◽

Lei Liu

Keyword(s):

Hydrogen Peroxide ◽

Chemical Synthesis ◽

Late Stage ◽

Kinetic Resolution ◽

High Efficiency ◽

Bond Formation ◽

Bioactive Molecules ◽

Environmentally Benign ◽

Secondary Amines

AbstractCatalytic kinetic resolution of amines represents a longstanding challenge in chemical synthesis. Here, we described a kinetic resolution of secondary amines through oxygenation to produce enantiopure hydroxylamines involving N–O bond formation. The economic and practical titanium-catalyzed asymmetric oxygenation with environmentally benign hydrogen peroxide as oxidant is applicable to a range of racemic indolines with multiple stereocenters and diverse substituent patterns in high efficiency with efficient chemoselectivity and enantio-discrimination. Late-stage asymmetric oxygenation of bioactive molecules that are otherwise difficult to synthesize was also explored.

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Iridium Complex Catalyzed Hydrogen Production from Glucose and Various Monosaccharides

Catalysts ◽

10.3390/catal11080891 ◽

2021 ◽

Vol 11 (8) ◽

pp. 891

Author(s):

Ken-ichi Fujita ◽

Takayoshi Inoue ◽

Toshiki Tanaka ◽

Jaeyoung Jeong ◽

Shohichi Furukawa ◽

...

Keyword(s):

Hydrogen Production ◽

Catalytic System ◽

Catalytic Reaction ◽

Hydrogen Gas ◽

Water Soluble ◽

Starting Material ◽

Iridium Complex ◽

Production Of Hydrogen ◽

Bipyridine Ligand

A new catalytic system has been developed for hydrogen production from various monosaccharides, mainly glucose, as a starting material under reflux conditions in water in the presence of a water-soluble dicationic iridium complex bearing a functional bipyridine ligand. For example, the reaction of D-glucose in water under reflux for 20 h in the presence of [Cp*Ir(6,6′-dihydroxy-2,2′-bipyridine)(H2O)][OTf]2 (1.0 mol %) (Cp*: pentamethylcyclopentadienyl, OTf: trifluoromethanesulfonate) resulted in the production of hydrogen gas in 95% yield. In the present catalytic reaction, it was experimentally suggested that dehydrogenation of the alcoholic moiety at 1-position of glucose proceeded.

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Separation of phenols from oils using deep eutectic solvents and ionic liquids

Pure and Applied Chemistry ◽

10.1515/pac-2019-1119 ◽

2020 ◽

Vol 92 (10) ◽

pp. 1717-1731

Author(s):

Yucui Hou ◽

Zhi Feng ◽

Jaime Ruben Sossa Cuellar ◽

Weize Wu

Keyword(s):

Ionic Liquids ◽

Phenolic Compounds ◽

High Efficiency ◽

Deep Eutectic Solvents ◽

Environmentally Benign ◽

Organic Chemical ◽

Environmental Friendliness ◽

Oil Mixtures ◽

Organic Chemical Industry

AbstractPhenolic compounds are important basic materials for the organic chemical industry, such as pesticides, medicines and preservatives. Phenolic compounds can be obtained from biomass, coal and petroleum via pyrolysis and liquefaction, but they are mixtures in oil. The traditional methods to separate phenols from oil using alkaline washing are not environmentally benign. To solve the problems, deep eutectic solvents (DESs) and ionic liquids (ILs) have been developed to separate phenols from oil, which shows high efficiency and environmental friendliness. In this article, we summarized the properties of DESs and ILs and the applications of DESs and ILs in the separation of phenols and oil. There are two ways in which DESs and ILs are used in these applications: (1) DESs formed in situ using different hydrogen bonding acceptors including quaternary ammonium salts, zwitterions, imidazoles and amides; (2) DESs and ILs used as extractants. The effect of water on the separation, mass transfer dynamics in the separation process, removal of neutral oil entrained in DESs, phase diagrams of phenol + oil + extractant during extraction, are also discussed. In the last, we analyze general trends for the separation and evaluate the problematic or challenging aspects in the separation of phenols from oil mixtures.

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