Hydrogen Fluoride Catalysis Simons

Hydrogen Fluoride Catalysis J. H. Simons Entropy of Adsorption Charles Kemball... 

Simons (143) in a recent review of catalysis concludes that the catalytic activity of hydrogen fluoride must be related to its high acidity. For reactions in the hydrocarbon phase where the dielectric constant of the medium is too low for free ions, we would have to consider complexes of the type Ar HF and Ar HF BF3 which do not exclude ionic mechanisms. For reactions of methylbenzenes with liquid hydrochloric acid or hydrochloric acid and aluminum chloride, similar complexes might be found, and the existence of HAICI4 or HBF4 as such in the medium is unnecessary for an explanation of catalytic action. 

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