The influence of additives on orthogonal reaction pathways in the Mizoroki-Heck arylation of vinyl ethers

2021 ◽  
Author(s):  
Joseph Becica ◽  
Owen D. Glaze ◽  
Damian Hruszkewycz ◽  
Graham E Dobereiner ◽  
David Leitch
Keyword(s):  
Vinyl Ether ◽  
Reaction Pathways ◽  
Vinyl Ethers ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Heck Arylation

The Mizoroki-Heck arylation of electron-rich alkenes such as butyl vinyl ether often results in regioisomeric mixtures of products under typical reaction conditions. To discover new catalytic systems for achieving α-selective...

scholarly journals Recent Advances in Photocatalytic Transformation of Carbohydrates Into Valuable Platform Chemicals

2021 ◽  
Vol 3 ◽  
Author(s):  
Huan Chen ◽  
Kun Wan ◽  
Fangjuan Zheng ◽  
Zhuo Zhang ◽  
Hongyu Zhang ◽  
...  
Keyword(s):  
Solar Energy ◽  
Scientific Community ◽  
Value Added ◽  
Reaction Pathways ◽  
Future Perspective ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Selective Transformation ◽  
Platform Chemicals ◽  
Broad Interest

In response to the less accessible fossil resources and deteriorating environmental problems, catalytic conversion of the abundant and renewable lignocellulosic biomass to replace fossil resources for the production of value-added chemicals and fuels is of great importance. Depolymerization of carbohydrate and its derivatives can obtain a series of C5-C6 monosaccharides (e.g., glucose and xylose) and their derived platform compounds (e.g., HMF and furfural). Selective transformation of lignocellulose using sustainable solar energy via photocatalysis has attract broad interest from a growing scientific community. The unique photogenerated reactive species (e.g., h+, e−, •OH, •O2−, and 1O2), novel reaction pathways as well as the mild reaction conditions make photocatalysis a “dream reaction.” This review is aimed to provide an overview of the up-to-date contributions achieved in the selective photocatalytic transformation of carbohydrate and its derivatives. Photocatalytic methods, properties and merits of different catalytic systems are well summarized. We then put forward future perspective and challenges in this field.

Gold Catalyzed Hydroamination of Propargylic Alcohols: Controlling Divergent Reaction Pathways to Access 1,3-Aminoalcohols, 3-Hydroxyketones or 3-Aminoketones

2018 ◽  
Author(s):  
Victor Laserna ◽  
Tom Sheppard
Keyword(s):  
Gold Catalysis ◽  
Reaction Pathways ◽  
High Yield ◽  
Reaction Conditions ◽  
Propargylic Alcohols ◽  
Catalytic Quantity ◽  
Selective Formation ◽  
General Method

A versatile approach to the valorization of propargylic alcohols is reported, enabling controlled access to three different products from the same starting materials. Firstly, a general method for the hydroamination of propargylic alcohols with anilines is described using gold catalysis to give 3-hydroxy imines with complete regioselectivity. These 3-hydroxyimines can be reduced to give 1,3-aminoalcohols with high syn seletivity. Alternatively, by using a catalytic quantity of aniline, 3-hydroxyketones can be obtained in high yield directly from propargylic alcohols. Further manipulation of the reaction conditions enables the selective formation of 3-aminoketones via a rearrangement/hydroamination pathway.<br>

scholarly journals Selective Styrene Oxidation to Benzaldehyde over Recently Developed Heterogeneous Catalysts

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1680
Author(s):  
Marta A. Andrade ◽  
Luísa M. D. R. S. Martins
Keyword(s):  
Heterogeneous Catalysts ◽  
Carbon Materials ◽  
Oxygen Species ◽  
Styrene Oxidation ◽  
Reaction Conditions ◽  
Reactive Metal ◽  
Catalytic Systems ◽  
Tert Butyl Hydroperoxide ◽  
Metal Organic ◽  
Important Intermediate

The selective oxidation of styrene under heterogeneous catalyzed conditions delivers environmentally friendly paths for the production of benzaldehyde, an important intermediate for the synthesis of several products. The present review explores heterogeneous catalysts for styrene oxidation using a variety of metal catalysts over the last decade. The use of several classes of supports is discussed, including metal–organic frameworks, zeolites, carbon materials and silicas, among others. The studied catalytic systems propose as most used oxidants tert-butyl hydroperoxide, and hydrogen peroxide and mild reaction conditions. The reaction mechanism proceeds through the generation of an intermediate reactive metal–oxygen species by catalyst-oxidant interactions. Overall, most of the studies highlight the synergetic effects among the metal and support for the activity and selectivity enhancement.

scholarly journals Revisiting Catalytic Cycles: A Broader View Through the Energy Span Model

2020 ◽  
Author(s):  
Diego Garay-Ruiz ◽  
Carles Bo
Keyword(s):  
Catalytic Reaction ◽  
Reaction Mechanisms ◽  
Computational Study ◽  
Reaction Network ◽  
Co2 Hydrogenation ◽  
Level Of Detail ◽  
Reaction Pathways ◽  
Catalytic Systems ◽  
Computational Code ◽  
Catalytic Cycles

<div><div><div><p>The computational study of catalytic processes allows discovering really intricate and detailed reaction mechanisms that involve many species and transformations. This increasing level of detail can even result detrimental when drawing conclusions from the computed mechanism, as many co-existing reaction pathways can be in close com- petence. Here we present a reaction network-based implementation of the energy span model in the form of a computational code, gTOFfee, capable of dealing with any user-specified reaction network. This approach, compared to microkinetic simulations, enables a much easier and straightforward analysis of the performance of any catalytic reaction network. In this communication, we will go through the foundations and appli- cability of the underlying model, and will tackle the application to two relevant catalytic systems: homogeneous Co-mediated propene hydroformylation and heterogeneous CO2 hydrogenation over Cu(111).</p></div></div></div>

scholarly journals Successive Activation of C–H and C–O Bonds of Vinyl Ethers by a Diphosphine and Hydrido-Bridged Diiridium Complex

Inorganics ◽  
2019 ◽  
Vol 7 (10) ◽  
pp. 121
Author(s):  
Takahashi ◽  
Shimbayashi ◽  
Fujita
Keyword(s):  
Vinyl Ether ◽  
Bond Activation ◽  
Ethyl Vinyl Ether ◽  
Vinyl Ethers ◽  
Ethyl Vinyl

The reaction of [(Cp*Ir)2(μ-dmpm)(μ-H)][OTf] (2) [Cp* = η5-C5Me5, dmpm = bis(dimethylphosphino)methane] with 2,3-dihydrofuran gives [(Cp*IrH)2(μ-dmpm){μ-(2,3-dihydrofuranyl)}][OTf] (3) in an isolated yield of 70% via the C–H bond activation at the 5-position of 2,3-dihydrofuran. Complex 3 is slowly converted into [(Cp*Ir)2(μ-dmpm)(μ-C=C(H)CH2CH2OH)][OTf] (4) quantitatively via the proton-mediated C–O bond activation. The reaction of 2 with ethyl vinyl ether gives [(Cp*Ir)2(μ-dmpm)(μ-CH=CH2)][OTf] (5) in the isolated yield of 64% via the successive activation of C–H and C–O bonds.

scholarly journals Cyclopentadienone Iron Tricarbonyl Complexes-Catalyzed Hydrogen Transfer in Water

Molecules ◽  
2020 ◽  
Vol 25 (2) ◽  
pp. 421 ◽  
Author(s):  
Daouda Ndiaye ◽  
Sébastien Coufourier ◽  
Mbaye Diagne Mbaye ◽  
Sylvain Gaillard ◽  
Jean-Luc Renaud
Keyword(s):  
Metal Complexes ◽  
Hydrogen Transfer ◽  
Low Cost ◽  
Pure Water ◽  
Free Water ◽  
Water Soluble ◽  
Tricarbonyl Complex ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Iron Tricarbonyl

The development of efficient and low-cost catalytic systems is important for the replacement of robust noble metal complexes. The synthesis and application of a stable, phosphine-free, water-soluble cyclopentadienone iron tricarbonyl complex in the reduction of polarized double bonds in pure water is reported. In the presence of cationic bifunctional iron complexes, a variety of alcohols and amines were prepared in good yields under mild reaction conditions.

scholarly journals Direct Catalytic Conversion of CO2 to Cyclic Organic Carbonates under Mild Reaction Conditions by Metal—Organic Frameworks

Catalysts ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 34 ◽  
Author(s):  
Seong Huh
Keyword(s):  
Metal Organic Framework ◽  
Cycloaddition Reaction ◽  
Co2 Concentration ◽  
Reaction Conditions ◽  
Catalytic Systems ◽  
Heterogeneous Catalytic ◽  
Electrochemical Conversion ◽  
Modern Chemical ◽  
Metal Organic ◽  
Carbon Dioxide Co2

The reduction of the representative greenhouse gas, carbon dioxide (CO2), is significantly an important theme for the current research in the modern chemical world. For the last two decades, the development of new metal-organic framework (MOF) systems with highly selective capture of CO2, in the presence of other competing gaseous molecules, has flourished to capture or separate CO2 for environmental protection. Nonetheless, the ultimate resolution to lessen the atmospheric CO2 concentration may be in the chemical or electrochemical conversion of CO2 to other compounds. In this context, the catalytic cycloaddition reaction of CO2 into organic epoxides to produce cyclic carbonates is a more attractive method. MOFs are being proven as efficient heterogeneous catalytic systems for this important reaction. In this review, we collected very recent progress in MOF-based catalytic systems, fully operable under very mild reaction conditions (room temperature and 1 atm CO2).

Stereoselective Preparation of Precursors of α-C-(1→3)-Disaccharides

2005 ◽  
Vol 70 (9) ◽  
pp. 1411-1428 ◽  
Author(s):  
Petr Štěpánek ◽  
Ondřej Vích ◽  
Lukáš Werner ◽  
Ladislav Kniežo ◽  
Hana Dvořáková ◽  
...  
Keyword(s):  
Vinyl Ether ◽  
Vinyl Ethers ◽  
Chiral Catalyst ◽  
Substituted 1

The stereoselectivity of cycloaddition of sugar-containing substituted 1-(thiazol-2-yl)but-2-en-1-ones 1 and vinyl ethers was studied using the achiral vinyl ether/chiral catalyst as well as the chiral vinyl ether/achiral catalyst combinations. It has been shown that Eu(fod)3-catalyzed cycloaddition of oxadienes 1a-1e with the chiral vinyl ethers 9 and 10 affords stereoselectively almost pure cycloadducts 11a-11e and 12a-12e, respectively. The obtained cycloadducts are suitable precursors for the synthesis of α-C-(1→3)-disaccharides, containing 2-deoxy-arabino-hexopyranose moiety of D- or L-configuration.

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