scholarly journals Controlling Product Selectivity with Nanoparticle Composition in Tandem Chemo-Biocatalytic Styrene Oxidation

2021 ◽  
Author(s):  
Derik Wilbers ◽  
Joseph Brehm ◽  
Richard Lewis ◽  
Jacqueline Van Marwijk ◽  
Thomas Davies ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
Product Selectivity ◽  
Styrene Oxidation ◽  
One Pot ◽  
Potential Approach ◽  
Reaction Cascades

The combination of heterogeneous catalysis and biocatalysis into one-pot reaction cascades is a potential approach to integrate enzymatic transformations into existing chemical infrastructure. Peroxygenases, which can achieve clean C-H activation,...

One-Pot Reaction Cascades Using Star Polymers with Core-Confined Catalysts

2005 ◽  
Vol 117 (39) ◽  
pp. 6542-6545 ◽  
Author(s):  
Brett Helms ◽  
Steven J. Guillaudeu ◽  
Yu Xie ◽  
Meredith McMurdo ◽  
Craig J. Hawker ◽  
...  
Keyword(s):  
Star Polymers ◽  
One Pot ◽  
Reaction Cascades

scholarly journals Heterogeneous acidic catalysts for the tetrahydropyranylation of alcohols and phenols in green ethereal solvents

2018 ◽  
Vol 14 ◽  
pp. 1655-1659 ◽  
Author(s):  
Ugo Azzena ◽  
Massimo Carraro ◽  
Gloria Modugno ◽  
Luisa Pisano ◽  
Luigi Urtis
Keyword(s):  
Organic Chemistry ◽  
Heterogeneous Catalysis ◽  
Important Class ◽  
Green Solvents ◽  
Reaction Products ◽  
Reaction Conditions ◽  
One Pot ◽  
Acidic Catalysts ◽  
Set Up ◽  
Work Up

The application of heterogeneous catalysis and green solvents to the set up of widely employed reactions is a challenge in contemporary organic chemistry. We applied such an approach to the synthesis and further conversion of tetrahydropyranyl ethers, an important class of compounds widely employed in multistep syntheses. Several alcohols and phenols were almost quantitatively converted into the corresponding tetrahydropyranyl ethers in cyclopentyl methyl ether or 2-methyltetrahydrofuran employing NH4HSO4 supported on SiO2 as a recyclable acidic catalyst. Easy work up of the reaction mixtures and the versatility of the solvents allowed further conversion of the reaction products under one-pot reaction conditions.

An Efficient Benzoxaborole One‐Pot Synthesis by Silia Cat DPP‐Pd Heterogeneous Catalysis using Diboronic Acid

2018 ◽  
Vol 360 (14) ◽  
pp. 2757-2761 ◽  
Author(s):  
Kana Kunihiro ◽  
Laurence Dumais ◽  
Guillaume Lafitte ◽  
Emeric Varvier ◽  
Loïc Tomas ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
One Pot ◽  
One Pot Synthesis

Improved Protocols for Microwave-Assisted Cu(I)-Catalyzed Huisgen 1,3-Dipolar Cycloadditions

2007 ◽  
Vol 72 (8) ◽  
pp. 1014-1024 ◽  
Author(s):  
Pedro Cintas ◽  
Katia Martina ◽  
Bruna Robaldo ◽  
Davide Garella ◽  
Luisa Boffa ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
Microwave Irradiation ◽  
Ultrasound Irradiation ◽  
Conventional Heating ◽  
Dipolar Cycloaddition ◽  
One Pot ◽  
Click Reactions ◽  
Dipolar Cycloadditions ◽  
Microwave Assisted ◽  
New Applications

The Huisgen 1,3-dipolar cycloaddition of azides and acetylenes catalyzed by Cu(I) salts, leading to 1,2,3-triazoles, is one of the most versatile "click reactions". We have developed a series of optimized protocols and new applications of this reaction starting from several substrates, comparing heterogeneous vs homogeneous catalysis, conventional heating vs microwave irradiation or simultaneous microwave/ultrasound irradiation. Both non-conventional techniques strongly promoted the cycloaddition (bromide → azide → triazole), that could be conveniently performed in a one-pot procedure. This was feasible even with such bulky molecules as functionalized β-cyclodextrins (β-CD), starting from 61-O-tosyl-β-CD or from heptakis[6-O-(tert-butyldimethylsilyl)]-21-O-propargyl-β-CD. "Greener" heterogeneous catalysis with charcoal-supported Cu(II) or Cu(I) (prepared under ultrasound) was advantageously employed.

One-Pot Hydroacetylation of Menadione (Vitamin K3) to Menadiol Diacetate (Vitamin K4) by Heterogeneous Catalysis

2012 ◽  
Vol 354 (7) ◽  
pp. 1301-1306 ◽  
Author(s):  
Claudiu Dobrinescu ◽  
Elena E. Iorgulescu ◽  
Constantin Mihailciuc ◽  
Dan Macovei ◽  
Stefan Wuttke ◽  
...  
Keyword(s):  
Heterogeneous Catalysis ◽  
Vitamin K3 ◽  
One Pot

Einfache photochemische Synthese von Benzylphosphanen / Facile Photochemical Synthesis of Benzylphosphines

1994 ◽  
Vol 49 (12) ◽  
pp. 1606-1614 ◽  
Author(s):  
Gerhard Müller ◽  
Martin Waldkircher ◽  
Martin Winkler
Keyword(s):  
Photochemical Reaction ◽  
Large Scale ◽  
Photochemical Synthesis ◽  
Product Selectivity ◽  
One Pot ◽  
Good Product ◽  
Consecutive Reactions ◽  
Soxhlet Apparatus ◽  
Short Period ◽  
By Products

Facile large-scale synthesis of the benzyl-dibromo-phosphines RPBr2 (R = C6H5CH2, 3,5-Me2C6H3CH2, 2-BrC6H4CH2) is accomplished by the photochemical reaction of toluene, mesitylene, and 2-bromotoluene, respectively, with PBr3 in the absence of solvent. If the reactions are carried out up to 50% completion the amount of by-products formed is remark­ ably low, rarely exceeding 10% of the total amount of products formed. The selectivity of the photoreaction may be improved up to 98% if it is carried out in a modified Soxhlet apparatus which allows the predominant irradiation of only the starting materials. The appar­ ent limitations imposed by the low turnovers required to achieve good product selectivity are by far outweighed by the large amounts of desired products formed in a short period of time and by the easy recovery of unreacted starting material by distillation. Thus in the case of 2-BrC6H4CH2PBr2, in a typical run 94 g (261 mmol) of product may be isolated after 2.5 h of irradiation of 970 mmol of 2-BrC6H5CH3 and 1.39 mol of PBr3. In this case the turnover is 32%. the isolated yield 27%, and the by-product 2-methylphenyl-dibromo-phosphine only amounts to less than 2%. The benzyl-dibromo-phosphines are easily methylated with two equivalents of MeMgCl to give the respective benzyl-dimethyl-phosphines in 79-93% yield. Tertiary benzylphosphines MePRR′ (R = 2-BrC6H4CH2, R′ = Me3SiCH2; R = R′ = 2-BrC6H4CH2) are obtained in easy one-pot syntheses by consecutive reactions of 2-BrC6H4CH2PBr2 with Me3SiCH2MgCl and MeMgCl, and with 2-BrC6H4CH2MgBr and MeMgCl, respectively.

Single molecule study of samarium oxide nanoparticles as a purely heterogeneous catalyst for one-pot aldehyde chemistry

2016 ◽  
Vol 6 (19) ◽  
pp. 7113-7121 ◽  
Author(s):  
Gregory K. Hodgson ◽  
Stefania Impellizzeri ◽  
Juan C. Scaiano
Keyword(s):  
Heterogeneous Catalysis ◽  
Homogeneous Catalysis ◽  
Single Molecule ◽  
Metal Ion ◽  
Active Species ◽  
Oxide Nanoparticles ◽  
Samarium Oxide ◽  
One Pot ◽  
Catalytically Active

Heterogeneous catalysis holds distinct advantages over homogeneous catalysis; however, it is only truly advantageous if unaffected by metal ion leaching or in situ formation of a soluble catalytically active species.

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