A novel route to produce 4-t-butyltoluene by t-butylation of toluene with t-butylalcohol over mesoporous Al-MCM-41 molecular sieves

Development of a Supported Ionic Liquid Phase (SILP) Catalyst for Slurry‐Phase Friedel–Crafts Alkylations of Cumene

“…In this way, the amount of "free", acidic anions [Al 2 Cl 7 ] À and [Al 3 Cl 10 ] À is increased in the system as only the first layer of acidic ionic liquid should react with the basic surface sites of the support.…”

“…Obviously, the interaction of the acidic chloroaluminate with the untreated, dry SiO 2 surface (irreversible reaction of surface Si À OH groups with the acidic anions of the ionic liquid, [Al 2 Cl 7 ] À and [Al 3 Cl 10 ] À ) leads to this loss in acidity. The reduced acidity of the catalytic layer in case of the SILP-slurry system results in its lower ability to isomerizes the kinetic products into the thermodynamic mixture.…”

“…In this case, a recycling of the acidic, ionic catalyst phase is possible by decantation. [10,11] Another interesting point of chloroaluminate ionic liquids is their tunable acidity ranging from mildly Lewis acidity (e.g., [cation]Cl/AlCl 3 = 1/1.1) to very powerful Lewis acidity at the maximum solubility of AlCl 3 . The latter is reached at a 1/2 molar ratio in the case of [cation]Cl/AlCl 3 [12] and can reach up to 1/4.5 in the case of [cation]A C H T U N G T R E N N U N G [NTf 2 ]/AlCl 3 systems.…”

“…[2][3][4][5] These heterogeneous catalysts can be separated from the liquid reaction products very easily by filtration, allowing much simpler process schemes. However, these heterogeneous catalysts are usually less active than the homogeneous system so that longer reaction times and rather extreme reaction conditions are usually required.…”

Alkylation of Hydroquinone with tert-Butanol Catalyzed by Polymer-supported Sulfonimide

“…The tertbutylation of hydroquinone with tert-butanol is an electrophilic substitution reaction on the aromatic ring commonly via a carbenium ion mechanism [23]. In the presence of acid catalyst at high temperatures, tert-butanol gets dehydrated into isobutylene and water.…”