Autocatalytic Friedel‐Crafts Acylation of Arenes without Additional Catalyst and Additive

Abstract

A new and autocatalytic method was developed for Friedel‐Crafts acylation of arenes without additional catalyst and additive. A series of electron‐rich arenes underwent the acylation to give the targeted product in low to high yields by using aryl, alkyl and vinyl acyl chlorides as the acylating reagent, which gave an effective method for the preparation of diaryl ketones, alkyl aryl ketones and α,β‐unsaturated ketones. Preliminary mechanistic investigation suggested that the present acylation displayed an induction period and a sigmoid kinetic profile characteristic of autocatalytic systems, and the resulting H+ played a role of the catalyst.

Unraveling the reaction mechanism of AlCl3Lewis acid catalyzed acylation reaction of pyrene from the perspective of the molecular electron density theory

“…Several experimental and computational works devoted to the acylation of benzene or non-aromatic compounds can be found in the literature. 5,6 Olah et al 7 experimentally carried out the acylation reaction of benzene, alkylbenzenes, and halobenzenes with acetyl halides (fluoride, chloride and bromide) and acetic anhydride in the presence of variety of LA catalysts. For the authors, the nature of the acetylating ion (fluoride, chloride or bromide) was a key parameter affecting the ortho, meta and para isomer distribution.…”

Catalyst‐Free Hydrogenolysis of Lignin β‐O‐4 Ketone Models with Water as an H‐transfer Reagent

“…On the other hand, the above‐mentioned methods rely on the use of various catalysts. By comparison, catalyst‐free process should be more attractive from environmental and economic perspectives [12b,c] . Thus we have attempted to actualize this goal, and found that lignin β ‐O‐4 ketone models undergo smoothly the hydrogenolysis by light‐induced water‐donating transfer hydrogenation, which provided an example of catalyst‐free hydrogenolysis of lignin β ‐O‐4 ketone models with water as an H‐transfer reagent (Scheme 1).…”

Mechanism of Friedel–Crafts Acylation Using Metal Triflate in Deep Eutectic Solvents: An Experimental and Computational Study

“…Friedel–Crafts acylation reaction is one of the important reactions of synthetic aromatic ketones. , The common acylation reaction employs acyl chlorides, acid anhydrides, or carboxylic acids as acylating reagents in the presence of traditional catalysts including Lewis acids − (anhydrous ZnCl 2 , A1Cl 3 , FeCl 3 ) or Brønsted acids − (concentrated sulfuric acid, hydrochloric acid), nanoparticles, − ionic liquids, − metal triflates, , mesoporous zeolite, nitrogen-doped carbon, , metal oxides, heteropoly acids, , and solid superacids . Besides, several effective methods were applied to the Friedel–Crafts acylation reaction, including flow chemistry, ultrasound activation, and microwave irradiation …”