Aggregation in strong acid. A micelle of carbonium ions

1979 ◽  
Vol 101 (7) ◽  
pp. 1896-1898 ◽  
Author(s):  
F. M. Menger ◽  
J. M. Jerkunica
Keyword(s):  
Strong Acid ◽  
Carbonium Ions

Stable carbonium ions. XXXI. p-Anisonium and methylphenonium ion-formation via aryl participation in strong acid solution

1967 ◽  
Vol 89 (20) ◽  
pp. 5259-5265 ◽  
Author(s):  
George A. Olah ◽  
Melvin B. Comisarow ◽  
Eli. Namanworth ◽  
Brian G. Ramsey
Keyword(s):  
Acid Solution ◽  
Strong Acid ◽  
Ion Formation ◽  
Carbonium Ions ◽  
Aryl Participation

Acid Catalyzed Rearrangements of Structurally Constrained Tricarbonyl(trans-pentadienyl)iron Cations

1974 ◽  
Vol 52 (11) ◽  
pp. 2085-2097 ◽  
Author(s):  
C. R. Jablonski ◽  
T. S. Sorensen
Keyword(s):  
Positive Charge ◽  
Strong Acid ◽  
Order Process ◽  
Iron Cation ◽  
Acid Media ◽  
First Order ◽  
Bond Rotation ◽  
Carbonium Ions ◽  
Acid Catalyzed ◽  
Secondary Ion

Both the tricarbonyl(1,4-dimethylene-cis, cis, trans, cis-hexa-1,3-dienyl)iron (secondary) and the tricarbonyl(1,4-dimethylene-5-methyl-cis, cis, trans-hexa-1,3-dienyl)iron (tertiary) cations, which cannot convert to a 5h-cis pentadienyl system via a simple bond rotation, can be prepared at low temperature in strong acid media from their related alcohol complexes. The secondary as well as the tertiary ions rearrange to give the thermodynamically more stable tricarbonyl-(1-alkylcyclohexa-1,3-dienyl)iron cation via an acid catalyzed pseudo first order process. The rate of rearrangement of the secondary ion is much faster than that of the tertiary ion indicating a substantial amount of residual positive charge on the exocyclic (β) carbon in the complexed trans-pentadienyl carbonium ions.

Isobutane from acid-catalyzed dehydration of butanols

1970 ◽  
Vol 48 (22) ◽  
pp. 3545-3548 ◽  
Author(s):  
John Warkentin ◽  
Kenneth E. Hine
Keyword(s):  
Acid Solution ◽  
Hydride Transfer ◽  
Strong Acid ◽  
Isomeric Butanols ◽  
Carbonium Ions ◽  
Acid Catalyzed

Dehydration of the four isomeric butanols by strong acid at about 160° gives a C4-fraction containing isobutane as well as the isomeric butenes. Isobutane probably arises by hydride transfer, from one or more donors including the substrate alcohol and hydrocarbons formed from it in the medium, to one or more carbonium ions including the t-butyl cation. Materials which react with 2,4-dinitrophenylhydrazine reagent to form 2,4-dinitrophenylhydrazones can be swept out of the hot acid solution with a stream of nitrogen.

Preparation of Strong Acid Catalysts by Sulfate Treatment of Calcined Boehmite

1992 ◽  
Vol 57 (11) ◽  
pp. 2241-2247 ◽  
Author(s):  
Tomáš Hochmann ◽  
Karel Setínek
Keyword(s):  
Catalytic Activity ◽  
Surface Area ◽  
Aluminum Sulfate ◽  
Solid Acid ◽  
Strong Acid ◽  
Acid Strength ◽  
Solid Acid Catalysts ◽  
Acid Catalysts ◽  
Preparation Methods ◽  
Indicator Method

Solid acid catalysts with acid strength of -14.52 < H0 < -8.2 were prepared by sulfate treatment of the samples of boehmite calcined at 105-800 °C. Two preparation methods were used: impregnation of the calcined boehmite with 3.5 M H2SO4 or mixing of the boehmite samples with anhydrous aluminum sulfate, in both cases followed by calcination in nitrogen at 650 °C. The catalysts were characterized by measurements of surface area, adsorption of pyridine and benzene, acid strength measurements by the indicator method and by catalytic activity tests in the isomerization of cyclohexene, p-xylene and n-hexane. Properties of the catalysts prepared by both methods were comparable.

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