Catalytic Acetylation of Aromatics with Metal Chlorides and Solid Acids − a Comparative Study

Evaluation of catalytic performances of selected metal chlorides such as AlCl3, SnCl4, ZnCl2, FeCl3, InCl3 and GaCl3 with solid acids such as sulfated zirconia, and zeolite beta was accomplished for acetylation of anisole, toluene and naphthalene. Presence of super acidity (Lewis or Bronsted acid) is found to be indispensable for activation of substrates towards acetylation reactions. In addition, presence of redox centers would further complement with the Lewis acid sites rendering catalytic stamina against deactivation. Strength of Lewis acid basically determines the activity of the metal chlorides towards acetylation. Among the Lewis acids investigated, FeCl3, InCl3 and GaCl3 exhibit their catalytic behaviour mostly through redox property as is evident from the conservation of Turn over number even after first cycle. Sulfated zirconia surpasses all the acid catalysts including metal chlorides and exhibits extended catalytic activity in acetylation of anisole. The pre-eminence of sulphated zirconia over other catalytic systems is owing to the synergistic effect of Lewis and Bronsted acidity.

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Merging gold catalysis, organocatalytic oxidation, and Lewis acid catalysis for chemodivergent synthesis of functionalized oxazoles from N-propargylamides

Chemical Communications ◽

10.1039/c7cc05746f ◽

2017 ◽

Vol 53 (75) ◽

pp. 10366-10369 ◽

Cited By ~ 20

Author(s):

Shaoyu Mai ◽

Changqing Rao ◽

Ming Chen ◽

Jihu Su ◽

Jiangfeng Du ◽

...

Keyword(s):

Transition Metal ◽

Lewis Acid ◽

Lewis Acids ◽

Acid Catalysis ◽

Gold Catalysis ◽

One Pot ◽

Catalytic Systems ◽

One Pot Synthesis ◽

The One ◽

Cationic Gold

Novel catalytic systems consisting of cationic gold complexes, N-hydroxyphthalimide (NHPI), and transition-metal-based Lewis acids have been developed for the one-pot synthesis of functionalized oxazoles.

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Measurements of number and strength distribution of Brønsted and Lewis acid sites on sulfated zirconia by ammonia IRMS–TPD method

Applied Catalysis A General ◽

10.1016/j.apcata.2008.01.033 ◽

2008 ◽

Vol 340 (1) ◽

pp. 76-86 ◽

Cited By ~ 35

Author(s):

Naonobu Katada ◽

Takuya Tsubaki ◽

Miki Niwa

Keyword(s):

Lewis Acid ◽

Sulfated Zirconia ◽

Acid Sites ◽

Strength Distribution ◽

Lewis Acid Sites ◽

Brønsted And Lewis Acid

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Nature of Catalytically Active Sites over Solid Acids. I. Selective Poisoning of Lewis Acid Sites on Silica–Alumina with Pyridine and Its Application to Olefin Polymerization

Bulletin of the Chemical Society of Japan ◽

10.1246/bcsj.49.1788 ◽

1976 ◽

Vol 49 (7) ◽

pp. 1788-1793 ◽

Cited By ~ 22

Author(s):

Koichi Mizuno ◽

Masanori Ikeda ◽

Toshiaki Imokawa ◽

Jun-ichiro Take ◽

Yukio Yoneda

Keyword(s):

Lewis Acid ◽

Active Sites ◽

Olefin Polymerization ◽

Acid Sites ◽

Solid Acids ◽

Lewis Acid Sites ◽

Catalytically Active ◽

Silica Alumina

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Solid Acids for the Reaction of Bioderived Alcohols into Ethers for Fuel Applications

Catalysts ◽

10.3390/catal9020172 ◽

2019 ◽

Vol 9 (2) ◽

pp. 172 ◽

Cited By ~ 1

Author(s):

Federica Zaccheria ◽

Nicola Scotti ◽

Nicoletta Ravasio

Keyword(s):

Physical Properties ◽

Lignocellulosic Biomass ◽

Lewis Acid ◽

Product Distribution ◽

Acid Sites ◽

Solid Acids ◽

Lewis Acid Sites ◽

Hydroxymethyl Furfural ◽

Brønsted And Lewis Acid

The use of solids acids in the synthesis of ethers suitable to be used as fuels or fuel additives were reviewed in a critical way. In particular, the role of Brønsted and Lewis acid sites was highlighted to focus on the pivotal role of the acidity nature on the product distribution. Particular emphasis is given to the recently proposed ethers prepared starting from furfural and 5-hydroxymethyl furfural. Thus, they are very promising products that can be derived from lignocellulosic biomass and bioalcohols and possess very interesting chemical and physical properties for their use in the diesel sector.

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Kinetics and Mechanism of Acetalisation of Furfural to Furfural Diethyl Acetal with Ni–Al Layered Double Hydroxides Containing Lewis Acid Sites

Progress in Reaction Kinetics and Mechanism ◽

10.3184/146867817x15066861009956 ◽

2018 ◽

Vol 43 (1) ◽

pp. 21-29 ◽

Cited By ~ 3

Author(s):

Yali Du ◽

Yalin Feng ◽

Chunlei Zou ◽

Xu Wu ◽

Wei Huang

Keyword(s):

Lewis Acid ◽

Catalytic Mechanism ◽

Catalytic Performance ◽

Acid Sites ◽

Diethyl Acetal ◽

Lewis Acid Sites ◽

Hydrolysis Method ◽

Catalytic Behaviour ◽

Double Hydroxide ◽

Double Hydroxides

The nitrate form of Ni–Al layered double hydroxide (denoted as Ni–Al–NO3-LDH) and the corresponding carbonate form (denoted as Ni–Al–CO3-LDH) were tunably fabricated by the hexamethylenetetramine hydrolysis method. A catalytic behaviour investigation proved Ni–Al–CO3-LDH to be an ineffective catalyst, while for Ni–Al–NO3-LDH excellent catalytic activity and reusability were obtained, in the acetalisation of furfural to furfural diethyl acetal. Characterisation and analysis revealed that the appearance of Lewis acid sites in Ni–Al–NO3-LDH was responsible for its excellent catalytic performance. The acquired kinetic parameters confirmed that this reaction was a first-order process and the apparent activation energy was 36.28 kJ mol−1, which is in reasonable agreement with the theoretical result of 38.57 kJ mol−1. Additionally, apart from the typical Brønsted acid catalytic mechanism, a possible Lewis acid catalytic mechanism was probed theoretically.

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Lewis acids immobilized in ionic liquid – application for the acetal synthesis

Polish Journal of Chemical Technology ◽

10.2478/pjct-2013-0049 ◽

2013 ◽

Vol 15 (3) ◽

pp. 78-80 ◽

Cited By ~ 2

Author(s):

Ewa Janus

Keyword(s):

Ionic Liquid ◽

Catalytic Activity ◽

Lewis Acids ◽

Metal Chloride ◽

Triethyl Orthoformate ◽

High Yield ◽

Catalytic Systems ◽

Metal Chlorides ◽

Acetalization Reaction

Abstract Catalytic systems composed of metal chloride (InCl3, ScCl3, YCl3, YbCl3, LaCl3, BiCl3, ZnCl3 and CuCl3) and 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)-imide, [C1C4Pyrr][NTf2] as ionic liquid were prepared. Catalytic activity of all the systems were compared in acetalization reaction between cyclohexanone and triethyl orthoformate. 1,1-Diethoxycyclohexane were formed with high yield and the selectivity at 0°C within 5 minutes. Selected metal chlorides immobilized in ionic liquid were recycled 5 times without a decrease in their activities

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Rational Design of Metal Oxide Solid Acids for Sugar Conversion

Catalysts ◽

10.3390/catal9110907 ◽

2019 ◽

Vol 9 (11) ◽

pp. 907 ◽

Cited By ~ 1

Author(s):

Takagaki

Keyword(s):

Metal Oxide ◽

Metal Oxides ◽

Lewis Acid ◽

Acid Sites ◽

Solid Acids ◽

Amorphous Metal ◽

Bronsted Acid ◽

Brønsted Acid ◽

Brönsted Acid ◽

Amorphous Metal Oxides

Aqueous-phase acid-catalyzed reactions are essential for the conversion of cellulose-based biomass into chemicals. Brønsted acid and Lewis acid play important roles for these reactions, including hydrolysis of saccharides, isomerization and epimerization of aldoses, conversion of d-glucose into 5-hydroxymethylfurfural, cyclodehydration of sugar alcohols and conversion of trioses into lactic acid. A variety of metal oxide solid acids has been developed and applied for the conversion of sugars so far. The catalytic activity is mainly dependent on the structures and types of solid acids. Amorphous metal oxides possess coordinatively unsaturated metal sites that function as Lewis acid sites while some crystal metal oxides have strong Brønsted acid sites. This review introduces several types of metal oxide solid acids, such as layered metal oxides, metal oxide nanosheet aggregates, mesoporous metal oxides, amorphous metal oxides and supported metal oxides for sugar conversions.

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