Zeolite Catalysts as Solid Solvents in Fine Chemicals Synthesis

Identification of Active Surface Species for Friedel–Crafts Acylation and Koch Carbonylation Reactions by in situ Solid‐State NMR Spectroscopy

“…We must note that adsorbed PMAP appears about 10 ppm high-field shifted with respect to the free compound (d = 198 ppm); this is indicative of strong adsorption on the zeolite, which can contribute to catalyst deactivation. [20] The spectrum of Figure 2 c shows that, at longer reaction times, the intensity of the signal of PMAP at 208 ppm progressively increases at the expense of the signal at 168 ppm, which indicates that the covalently bound acetylzeolite species is a reactive intermediate in the Friedel-Crafts acylation reaction. It is worth noting the absence of any signal at 150-160 ppm in Figure 2 that could be attributed to H 3 C À C + = O (Figure 1 c), which suggests that this species is not formed.…”

A Novel Friedel-Crafts Acylation Reaction of Anisole for Production of 4-Methoxyacetophenone with High Selectivity and Sufficient Reusability of Mordenite Zeolite Catalyst

“…In general textbook of organic chemistry, this reaction can be promoted by Lewis acid catalysts such as AlCl 3 , HF and BF 3 using acid chlorides and alkylhalides for pro-ducing corresponding substituted aromatics. Unfortunately these conventional reactions produce large amounts of waste after the reaction by work-up, neutralization of catalyst and/or used reagent.…”

“…Thus necessity of alternating to conventional catalytic reaction and a wide spreading concern for environmental benignity have triggered the development of economic and green chemical processes for Friedel-Crafts reaction. In researches of eco-friendly Friedel-Crafts acylations of anisole, usage of zeolite has been widely developed as promising catalysts as well as the index of shape selectivity of the zeolite due to their validities of three dimensional pore structure, so far [1] [2] [3]. Among the examined zeolite catalysts, reports on using BEA zeolites have been paid much attention, for example, using toluene as solvent [4] [5], neat conditions [6] [7] [8] and fixedbed vapor phase reaction [9].…”

Efficient Acylation of Anisole over Hierarchical Porous ZSM‐5 Structure

“…Conventionally, the method used to prepare aromatic ketones is the acylation of aromatics with activated derivatives of carboxylic acids, such as acid halides and anhydrides, in the presence of soluble Lewis acids such as AlCl 3 , FeCl 3 , or ZnCl 3 as catalysts [3]. Recently, a large number of studies were carried out with solid acids for the acylation of anisole in order to make the process greener [4][5][6][7][8][9][10]. Also recent is the amount of emphasis placed on the synthesis and application of meso-/ macroporous catalysts for fine chemical synthesis [11][12][13][14][15].…”