Stabilities of nickel–alkyl compounds

1970 ◽  
Vol 48 (21) ◽  
pp. 3443-3446 ◽  
Author(s):  
J. Thomson ◽  
M. C. Baird
Keyword(s):  
Thermal Decomposition ◽  
Olefin Isomerization ◽  
Xylene Solution ◽  
Isomerization Catalyst

The compounds π-C5H5Ni(PPh3)R (R = Me, Et, n-Pr, iso-Pr, n-Bu, sec-Bu, iso-Bu) have been prepared and characterized. Thermal decomposition of these compounds in xylene solution yields, in all cases except the methyl, an olefin and an olefin isomerization catalyst.

Identifying and Evading Olefin Isomerization Catalyst Deactivation Pathways Resulting from Ion-Tunable Hemilability

ACS Catalysis ◽  
2020 ◽  
Vol 10 (21) ◽  
pp. 13019-13030
Author(s):  
Henry M. Dodge ◽  
Matthew R. Kita ◽  
Chun-Hsing Chen ◽  
Alexander J. M. Miller
Keyword(s):  
Catalyst Deactivation ◽  
Olefin Isomerization ◽  
Isomerization Catalyst

Experimental and Computational Study of the Thermal Decomposition of 3-Methyl-3-buten-1-ol inm-Xylene Solution

2014 ◽  
Vol 46 (7) ◽  
pp. 363-369 ◽  
Author(s):  
JAIRO QUIJANO ◽  
PABLO RUIZ ◽  
RAFAEL NOTARIO ◽  
EDILMA ZAPATA ◽  
JAÍR GAVIRIA
Keyword(s):  
Thermal Decomposition ◽  
Computational Study ◽  
Xylene Solution

Thermal decomposition of 4-hydroxy-2-butanone in m -xylene solution: Experimental and computational study

2012 ◽  
Vol 44 (6) ◽  
pp. 407-413 ◽  
Author(s):  
Juliana Murillo ◽  
Diana Henao ◽  
Ederley Vélez ◽  
Carolina Castaño ◽  
Jairo Quijano ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Computational Study ◽  
Xylene Solution

Thermal decomposition of methyl β-hydroxyesters inm-xylene solution

2006 ◽  
Vol 39 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Edilma Zapata ◽  
Jair Gaviria ◽  
Jairo Quijano
Keyword(s):  
Thermal Decomposition ◽  
Xylene Solution

Experimental and computational study of the thermal decomposition of 3-buten-1-ol in m-xylene solution

2013 ◽  
Vol 24 (6) ◽  
pp. 1811-1816 ◽  
Author(s):  
Víctor López ◽  
Jairo Quijano ◽  
Sofía Luna ◽  
Pablo Ruiz ◽  
Diego Rios ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Computational Study ◽  
Xylene Solution

scholarly journals Selecting Double Bond Positions with a Single Cation- Responsive Iridium Olefin Isomerization Catalyst

2020 ◽  
Author(s):  
Andrew M. Camp ◽  
Matthew R. Kita ◽  
Thomas P. Blackburn ◽  
Henry M. Dodge ◽  
Chun-Hsing Chen ◽  
...  
Keyword(s):  
Mechanistic Model ◽  
Computational Studies ◽  
Olefin Isomerization ◽  
Positional Isomerization ◽  
Iridium Catalyst ◽  
Commodity Chemicals ◽  
Covalent Modifications ◽  
Insight Into ◽  
Selective Access ◽  
Isomerization Catalyst

<div><div><div><p>The catalytic transposition of double bonds holds promise as an ideal route to alkenes with value as fragrances, commodity chemicals, and pharmaceuticals; yet, selective access to specific isomers is a challenge, requiring independent development of different catalysts for different products. In this work, a single cation-responsive iridium catalyst is developed for the selective production of either of two different internal alkene isomers. In the absence of salts, a single positional isomerization of 1-butene derivatives furnishes 2-alkenes with exceptional regioselectivity and stereoselectivity. The same catalyst, in the presence of Na+, mediates two positional isomerizations to produce 3-alkenes. The synthesis of new iridium pincer-crown ether catalysts based on an aza-18-crown-6 ether proved instrumental in achieving cation-controlled selectivity. Experimental and computational studies guided the development of a mechanistic model that explains the observed selectivity for various functionalized 1-butenes, providing insight into strategies for catalyst development based on non-covalent modifications.</p></div></div></div>

scholarly journals Selecting Double Bond Positions with a Single Cation- Responsive Iridium Olefin Isomerization Catalyst

2020 ◽  
Author(s):  
Andrew M. Camp ◽  
Matthew R. Kita ◽  
Thomas P. Blackburn ◽  
Henry M. Dodge ◽  
Chun-Hsing Chen ◽  
...  
Keyword(s):  
Mechanistic Model ◽  
Computational Studies ◽  
Olefin Isomerization ◽  
Positional Isomerization ◽  
Iridium Catalyst ◽  
Commodity Chemicals ◽  
Covalent Modifications ◽  
Insight Into ◽  
Selective Access ◽  
Isomerization Catalyst

<div><div><div><p>The catalytic transposition of double bonds holds promise as an ideal route to alkenes with value as fragrances, commodity chemicals, and pharmaceuticals; yet, selective access to specific isomers is a challenge, requiring independent development of different catalysts for different products. In this work, a single cation-responsive iridium catalyst is developed for the selective production of either of two different internal alkene isomers. In the absence of salts, a single positional isomerization of 1-butene derivatives furnishes 2-alkenes with exceptional regioselectivity and stereoselectivity. The same catalyst, in the presence of Na+, mediates two positional isomerizations to produce 3-alkenes. The synthesis of new iridium pincer-crown ether catalysts based on an aza-18-crown-6 ether proved instrumental in achieving cation-controlled selectivity. Experimental and computational studies guided the development of a mechanistic model that explains the observed selectivity for various functionalized 1-butenes, providing insight into strategies for catalyst development based on non-covalent modifications.</p></div></div></div>

Selecting Double Bond Positions with a Single Cation-Responsive Iridium Olefin Isomerization Catalyst

2021 ◽  
Vol 143 (7) ◽  
pp. 2792-2800
Author(s):  
Andrew M. Camp ◽  
Matthew R. Kita ◽  
P. Thomas Blackburn ◽  
Henry M. Dodge ◽  
Chun-Hsing Chen ◽  
...  
Keyword(s):  
Double Bond ◽  
Olefin Isomerization ◽  
Isomerization Catalyst

Applications of Photoelectron Microscopy

1976 ◽  
Vol 34 ◽  
pp. 506-507
Author(s):  
William J. Baxter
Keyword(s):  
Electron Microscopy ◽  
Thermal Decomposition ◽  
Chemical Composition ◽  
Ultraviolet Radiation ◽  
Thin Layer ◽  
Edge Effects ◽  
Electron Optics ◽  
Surface Layers ◽  
Crystalline Orientation ◽  
Fluorescent Screen

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.

Preparation and characterisation of vanadium pentoxide supported rhodium catalyst

1988 ◽  
Vol 46 ◽  
pp. 946-947
Author(s):  
A. Legrouri
Keyword(s):  
Aqueous Solution ◽  
Thermal Decomposition ◽  
Physicochemical Properties ◽  
Surface Area ◽  
Vanadium Pentoxide ◽  
High Purity ◽  
Gas Adsorption ◽  
Rhodium Catalyst ◽  
Optical Methods ◽  
Reducible Oxides

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.

Sign in / Sign up

Export Citation Format

Share Document