ChemInform Abstract: Electronegativity and Lewis Acid Strength.

ChemInform ◽  
1990 ◽  
Vol 21 (33) ◽  
Author(s):  
I. D. BROWN ◽  
A. SKOWRON
Keyword(s):  
Lewis Acid ◽  
Acid Strength

Empirical Lewis acid strengths for 135 cations bonded to oxygen

2017 ◽  
Vol 73 (5) ◽  
pp. 956-961 ◽  
Author(s):  
Olivier Charles Gagné ◽  
Frank Christopher Hawthorne
Keyword(s):  
Lewis Acid ◽  
Strong Correlation ◽  
Ionization Energy ◽  
Acid Strength ◽  
Lewis Base

New and updated Lewis acid strengths are listed for 135 cations bonded to oxygen for use with published Lewis base strengths. A strong correlation between Lewis acid strength and ionization energy is shown, and correlation with electronegativity is confirmed.

INFRARED SPECTRA OF 2,6-DIMETHYL-4-PYRONE COMPLEXES

1961 ◽  
Vol 39 (6) ◽  
pp. 1184-1189 ◽  
Author(s):  
Denys Cook
Keyword(s):  
Complex Formation ◽  
Oxygen Atom ◽  
Carbonyl Group ◽  
Lewis Acid ◽  
Frequency Band ◽  
Infrared Spectra ◽  
Donor Site ◽  
Carbonyl Oxygen ◽  
Acid Strength ◽  
Group A

The infrared spectra of 2,6-dimethyl-4-pyrone in solution, and in complexes with HgCl2, ZnCl2, BF3, SbCl5, and HBr have been recorded. A band at 1639 cm−1 in the free pyrone moves to progressively lower frequencies in the complexes as the Lewis acid strength increases, identifying this band as the carbonyl stretching frequency and the donor site as the carbonyl group. A higher-frequency band, at 1678 cm−1 in the free pyrone, moves to lower frequency on complex formation, but to a much smaller extent, and is to be identified with a stretching mode of the ring. The site of protonation in 2,6-dimethyl-4-pyrone salts has been unequivocally shown to be the carbonyl oxygen atom.

Electronegativity and Lewis acid strength

1990 ◽  
Vol 112 (9) ◽  
pp. 3401-3403 ◽  
Author(s):  
I. D. Brown ◽  
A. Skowron
Keyword(s):  
Lewis Acid ◽  
Acid Strength

Borane catalyzed polymerization and depolymerization reactions controlled by Lewis acid strength

2021 ◽  
Author(s):  
Kori Anne Andrea ◽  
Mikhailey Diane Wheeler ◽  
Francesca M. Kerton
Keyword(s):  
Lewis Acid ◽  
Acid Strength ◽  
Block Copolymerization ◽  
Catalyzed Polymerization

Triphenylborane catalyzes the polymerization of anhydrides and epoxides along with the block copolymerization of anhydride/ epoxides with epoxides/CO2. Switching to the more Lewis acidic borane, tris(pentafluorophenyl)borane, the carbonate block of...

Influence of Preparation Conditions on the Acidity of WO3/ZrO2 Solid Superacid

2011 ◽  
Vol 233-235 ◽  
pp. 1502-1506 ◽  
Author(s):  
Ping Xu ◽  
Min Wei Wang ◽  
Jia Wei Qu ◽  
Ren Lang Wang ◽  
Jian Wang
Keyword(s):  
Lewis Acid ◽  
Acid Sites ◽  
Acid Strength ◽  
Lewis Acid Sites ◽  
Solid Superacid ◽  
Preparation Conditions ◽  
Acid Type ◽  
Loading Amount ◽  
Superacid Catalysts ◽  
Adsorption Desorption

WO3/ZrO2 solid superacid catalysts were prepared by coprecipitation and impregnation, then were characterized by XRD, N2 adsorption-desorption, Hammett indicator and pyridine chemisorption IR. The acid strength, acid type, acid volume, etc were compared under the different preparation conditions. The results indicated that the catalyst prepared by coprecipitation had stronger acid strength than the catalyst prepared by impregnation. The samples prepared by impregnation had more Lewis acid sites. With the increasing of the W/Zr ratio, the acid strength tended to increase at first and then decrease, and the catalyst with 10% WO3 loading amount had the strongest acidity. The higher the calcination temperature, the less the Lewis acid sites.

Sign in / Sign up

Export Citation Format

Share Document