The Alkylation of Aromatic Compounds by the Friedel‐Crafts Method

Abstract

Since the discovery by Friedel and Crafts that aluminum chloride catalyzes the condensation of alkyl and acyl halides with various aromatic compounds to effect substitution of an alkyl or acyl group for more or more hydrogen atoms of the aromatic compound, this reaction has been greatly extended in scope with respect to alkylating or acylating agents and catalysts. The use of aluminum chloride as a catalyst was studied by Thomas. Aspects of this study appeared in an earlier volume of this series. The present discussion is limited to the direct alkyl, cycloalky, or aralkyl residues containing no functional groups into various aromatic compounds under various catalysts, such as e.g., aluminum trichloride, zinc dichloride, and hydrogen fluoride. The alkylating agents include olefins, highly strained cycloparaffins, polyalkylbenzenes, alkyl halides, alcohols, esters, of inorganic and organic acids, and ethers. The aromatic compound may be e.g., a hydrocarbon, an aryl chloride, or bromide, a mono‐or polyhdrydric phenol or its ether. The Friedel‐Crafts process is frequently the most useful method for the introduction of an alkyl group.

A general route for RuO2deposition on metal oxides from RuO4

“…Friedel-Crafts alkylations using CH 2 Cl 2 as a methylene source have been effectively reported. 10 This prompted us to perform the reaction in different solvents. Treatment of an equimolar mixture of 3 and 4 with AlCl 3 in nitrobenzene or 1,2-dichloroethane gave only linear oligomers and no cyclization product could be detected.…”

A New Three-Component Photo-Initiating System for Visible Light Recording of Volume Holograms with Single-Pulsed Laser

“…Scheme 5 [14][15][16]. The electron acceptors 2-4 had to be synthesized from the respective commercially available precursors by an Friedel-Crafts alkylation using carbon tetrachloride as highly efficient electrophilic reagent [17]. The products were obtained as crystalline solids in good-to-excellent yields.…”

Self-foaming polymers: Opportunities for the next generation of personal protective equipment

“…With the less reactive monomers, pMBC and mMBC, the addition of a crosslinker, the trioxane (TO), was required to observe the formation of a foam. TO promoted the cross-linking of the growing polyaromatic resin by the formation of methylene bridges between aromatic rings through Friedel-Crafts alkylation [165] (Figure 12c). This observation indicates that, for these monomers, the increase of the molecular weight resulting from the cationic polymerization of the activated carbeniums was not sufficient to promote the viscosification of the polymeric matrix, and in return the efficient trapping of the blowing agent (CO2 and H2O).…”