K2CO3-promoted formation of aryl esters from primary aryl amides by the acyl–acyl exchange process

2016 ◽  
Vol 14 (16) ◽  
pp. 3869-3872 ◽  
Author(s):  
Yongjun Bian ◽  
Xingyu Qu
Keyword(s):  
Exchange Reaction ◽  
Exchange Process ◽  
Reaction Conditions ◽  
Acyl Exchange

A new acyl–acyl exchange reaction has been developed for the formation of aryl esters from primary aryl amides. The reaction could occur under mild reaction conditions with catalytic quantities of K2CO3, and could afford moderate to good yields of the desired products.

13C NMR-spektroskopische Untersuchungen an Äthylaluminiumverbindungen / 13C NMR Spectroscopic Investigations of Ethylaluminium Compounds

1976 ◽  
Vol 31 (6) ◽  
pp. 730-736 ◽  
Author(s):  
R. Rottler ◽  
C. G. Kreiter ◽  
G. Fink
Keyword(s):  
Temperature Dependence ◽  
Exchange Reaction ◽  
13C Nmr ◽  
Line Shape ◽  
Nmr Spectra ◽  
Exchange Process ◽  
Kcal Mole ◽  
Line Shapes ◽  
Calculated Line ◽  
C Nmr

The 13C NMR spectra of the ethylaluminium compounds [Al(C2H5)xCl3_x]2 x = 1, 1,5, 2 and 3 are presented and factors governing the temperature dependence of the line shape are discussed. The exchange reaction of terminal ethyl groups for chlorine ligands and ethyl ligands, resp., in ethylaluminium-sesquichloride was investigated by fitting the calculated line shapes to the observed spectra.The energy of activation of this exchange process was determined as to be 12,3 ‡ 1,5 kcal/mole. The synthesis of 13C2-[Al(C2H5)Cl2]2 is described.

scholarly journals Substitution of Ca2+ in Calcite by Sn2+ and Sr2+ cations through ion exchange characterized by X-ray absorption and photoelectron spectroscopies

MRS Advances ◽  
2021 ◽  
Author(s):  
Jonathan B. Junio ◽  
Prae Chirawatkul ◽  
Marlon T. Conato ◽  
Candy C. Mercado
Keyword(s):  
Ion Exchange ◽  
Cation Exchange ◽  
Exchange Reaction ◽  
Exchange Process ◽  
X Ray ◽  
Exchange Transformation ◽  
Ion Exchange Process ◽  
Cation Exchange Reaction ◽  
Carbonate Material ◽  
X Ray Absorption

AbstractTin (Sn2+) and strontium (Sr2+), two potential alternatives to lead (Pb2+) in perovskite formation, were explored in transforming calcium carbonate (CaCO3) into a leaving group in a cation exchange reaction. This is the first part of a sequential ion exchange process in transforming calcite into a Pb-free perovskite material for perovskite solar cell applications. Calcite, a polymorph of CaCO3, was successfully transformed into strontianite (SrCO3) through a cation exchange reaction. In the Sn substitution reaction on the other hand, no SnCO3 formation was noted. Instead, oxides of Sn were formed. The wider spaces in between Ca2+ cations in (100) orientation account for the higher atomic Sn2+ and Sr2+ concentrations as compared to (001) orientation, where the cation movement is restricted. X-ray absorption and photoelectron spectroscopies were used to investigate the ion-exchange transformation of calcite towards the formation of an intermediate carbonate material. Graphic abstract

scholarly journals A Green Synthesis of Polylimonene Using Maghnite-H+, an Exchanged Montmorillonite Clay, as Eco-Catalyst

2019 ◽  
Vol 14 (1) ◽  
pp. 69 ◽  
Author(s):  
Hodhaifa Derdar ◽  
Mohammed Belbachir ◽  
Amine Harrane
Keyword(s):  
Reaction Time ◽  
Green Synthesis ◽  
Exchange Process ◽  
Gel Permeation Chromatography ◽  
Bulk Polymerization ◽  
Montmorillonite Clay ◽  
Scanning Calorimetry ◽  
Reaction Conditions ◽  
Ft Ir ◽  
Optimal Reaction

A new green polymerization technique to synthesis polylimonene (PLM) is carried out in this work. This technique consists of using Maghnite-H+ as eco-catalyst to replace Friedel-Crafts catalysts which are toxics. Maghnite-H+ is a montmorillonite silicate sheet clay which is prepared through a simple exchange process. Polymerization experiments are performed in bulk and in solution using CH2Cl2 as solvent. Effect of reaction time, temperature and amount of catalyst is studied, in order to find the optimal reaction conditions. The polymerization in solution leads to the best yield (48.5%) at -5°C for a reaction time of 6 h but the bulk polymerization, that is performed at 25°C, remains preferred even if the yield is lower (40.3%) in order to respect the principles of a green chemistry which recommend syntheses under mild conditions, without solvents and at room temperature. The structure of the obtained polymer (PLM) is confirmed by FT-IR and Nuclear Magnetic Resonance of proton (1H-NMR). The glass transition temperature (Tg) of the polylimonene is defined using Differential Scanning Calorimetry (DSC) and is between 113°C and 116°C. The molecular weight of the obtained polymer is determined by Gel Permeation Chromatography (GPC) analysis and is about 1360 g/mol. Copyright © 2019 BCREC Group. All rights reservedReceived: 26th May 2018; Revised: 11st September 2018; Accepted: 22nd September 2018; Available online: 25th January 2019; Published regularly: April 2019How to Cite: Derdar, H., Belbachir, M., Harrane, A. (2019). A Green Synthesis of Polylimonene Using Maghnite-H+, an Exchanged Montmorillonite Clay, as Eco-Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 14 (1): 69-78 (doi:10.9767/bcrec.14.1.2692.69-78)Permalink/DOI: https://doi.org/10.9767/bcrec.14.1.2692.69-78 

COS-triggered Oxygen/Sulfur Exchange of Isatins: Chemoselective Synthesis of Functionalized Isoindigos and Spirothiopyrans via Self-condensation and Thio-Diels-Alder Reaction

2022 ◽  
Author(s):  
Wei Chen ◽  
Hui Zhou ◽  
Bai-Hao Ren ◽  
Wei-Min Ren ◽  
Xiaobing Lu
Keyword(s):  
Exchange Reaction ◽  
Sulfur Atom ◽  
Carbonyl Sulfide ◽  
Alder Reaction ◽  
Diels Alder ◽  
Reaction Conditions ◽  
Diels Alder Reaction ◽  
Chemoselective Synthesis ◽  
Sulfur Exchange

Herein, we present the first organocatalytic oxygen/sulfur atom exchange reaction (O/S ER) of isatins by employing carbonyl sulfide (COS) as novel sulfuring reagent under mild reaction conditions. 8-Diazabicyclo[5.4.0] undec-7-ene (DBU),...

scholarly journals Studies of inositol analogues as inhibitors of the phosphoinositide pathway, and incorporation of 2-deoxy-2-fluoro-myo-inositol to give analogues of phosphatidylinositol intermediates

1991 ◽  
Vol 277 (2) ◽  
pp. 407-412 ◽  
Author(s):  
F McPhee ◽  
C P Downes ◽  
G Lowe
Keyword(s):  
Kinetic Analysis ◽  
Exchange Reaction ◽  
The Other ◽  
Exchange Reactions ◽  
Reaction Conditions ◽  
Competitive Inhibitors ◽  
Substantial Inhibition ◽  
Phosphoinositide Pathway

The incorporation of [3H]Ins into PtdIns by exchange of free and lipid-bound inositol moieties occurs via the action of at least two types of Mg2+/Mn(2+)-dependent enzymes in turkey erythrocytes. One is a nucleotide-independent PtdIns/Ins exchange enzyme and its function is, as yet, unknown, whereas the other is CMP-dependent and appears to be an exchange reaction catalysed by PtdIns synthase. The effects of analogues with modifications of the substituent at the 1-, 2-, 3-, 4- and 5-positions on the incorporation of [3H]Ins into PtdIns under both synthase and exchange reaction conditions were investigated in turkey erythrocytes. Analogues causing substantial inhibition of [3H]Ins incorporation were then used in kinetic experiments to determine the type of inhibition involved. The analogues 1-deoxy-1-fluoro-scyllo-inositol and 5-O-methyl-myo-inositol exhibited the greatest effects on the incorporation of [3H]Ins via both the synthase and exchange reactions, and the kinetic analysis indicated that they were competitive inhibitors of Ins. Ki values of 0.37 mM and 2.87 mM were observed for 1-deoxy-1-fluoro-scyllo-inositol under exchange and synthase reaction conditions respectively; similar Ki values of 0.26 mM and 2.80 mM were observed for 5-O-methyl-myo-inositol in the exchange and synthase reactions respectively. The ability of 1-deoxy-1-fluoro-scyllo-inositol and its diastereoisomer, 2-deoxy-2-fluoro-myo-inositol, to act as substrates for the synthase and exchange reactions in turkey erythrocytes was investigated. The radiolabelled derivative of the former analogue was not incorporated into phospholipids, whereas the radiolabelled derivative of the latter analogue was a poor substrate for the synthase and exchange enzymes. In the presence of ATP, the labelled analogue of PtdIns, derived from 2-deoxy-2-fluoro-myo-[2-3H]inositol, appeared to be converted into phosphorylated PtdIns analogues, presumably by the enzymes of the phosphoinositide pathway.

Stereoselective Synthesis of Vinyl Iodides through Copper(I)-Catalyzed Finkelstein-Type Halide-Exchange Reaction

Synthesis ◽  
2017 ◽  
Vol 49 (12) ◽  
pp. 2727-2732 ◽  
Author(s):  
Xiujuan Feng ◽  
Haixia Zhang ◽  
Wenbo Lu ◽  
Yoshinori Yamamoto ◽  
Abdulrahman Almansour ◽  
...  
Keyword(s):  
Exchange Reaction ◽  
Potassium Iodide ◽  
Efficient Method ◽  
Stereoselective Synthesis ◽  
Copper Catalyst ◽  
Reaction Conditions ◽  
Halide Exchange ◽  
Vinyl Iodides

An efficient method for the stereoselective synthesis of vinyl iodides is described. The reactions of vinyl bromides with potassium iodide proceed smoothly in the presence of a copper catalyst under mild reaction conditions to produce the corresponding vinyl iodides stereospecifically and in satisfactory to excellent yields.

Zur Kinetik der Ionenaustauscher III. Die Filmdiffusion bei vollständigen Umbeladungen

1969 ◽  
Vol 24 (6) ◽  
pp. 900-902
Author(s):  
Kurt Bunzel
Keyword(s):  
Ion Exchange ◽  
Exchange Reaction ◽  
Exchange Process ◽  
Ionic Composition ◽  
Selectivity Coefficient ◽  
Film Diffusion ◽  
Ion Exchange Process ◽  
Ion Exchange Reaction ◽  
Diffusion Controlled ◽  
Kinetics Of

The selectivity coefficient K21 of an ion-exchange process is in general a function of the ionic composition of the material. As a result, the value of K21 will change continuously during a com­plete conversion of the ion-exchanger. Equations for the kinetics of such a conversion with variable K21 are given for a film diffusion controlled ion-exchange reaction.

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