Ketonization Of Acetic Acid Research Articles

Oxiranyl β-Aminovinyl Ketones. 7. Synthesis of 5-Hydroxy-3-(1-oxo-2,3-epoxyalkyl)benzofurans

5-Hydroxy-3-(1-oxo-2,3-epoxyalkyl)benzofurans were obtained with yields of up to 81% by the reaction of p-benzoquinone with oxiranyl β-dimethylaminovinyl ketones in acetic acid.

Fluoro-containing Heterocycles. IV. Synthesis of Benzimidazole Derivatives

2-Mercapto-5,6-difluorobenzimidazole reacts with aliphatic and alicyclic ketones in acetic acid in the presence of catalytic amount of sulfuric acid to afford fluorinated derivatives of 2,3-disubstituted benz[4,5]imidazo[2,1-b][1,3]thiazoles. Reaction with aromatic α-haloketones occurs in another way: to furnish 2-phenylacylthio-5,6-difluorobenzimidazoles that in the system acetic anhydride-pyridine undergo cyclization into the corresponding fluorinated derivatives of benz[4,5]imidazo[2,1-b][1,3]thiazoles.

Catalytic Ketonization of Acetic Acid on Zn/Al Layered Double Hydroxides

Zn/Al Layered double hydroxides (LDHs) with various Zn:Al ratios were prepared, characterized by chemical analysis, PXRD, IR, thermal analysis, nitrogen adsorption-desorption and basic sites. The catalytic activity of samples calcined at 450°C for the ketonization of acetic acid was studied in a fixed bed catalytic reactor (10 mm id) with an on-line gas chromatograph. Amongst all, the sample with Zn:Al ratio 3:1 showed the highest surface area (103.5 m2/g) and yield of acetone (>89%) with high selectivity.

Studies on Indian Ocean Manganese Nodules: XI. Physicochemical Characterization and Catalytic Activity of Silver Oxide Mixed Manganese Nodules

The promoting effect of Ag2O on the physicochemical properties and catalytic activity of manganese nodules has been investigated. The surface area and surface oxygen increased with addition of Ag2O, reaching a maximum at 1 mol% of Ag, and then decreased with further addition of Ag2O. The catalytic activity of manganese nodules substantially increased with addition of Ag2O over a wide range (0.25–25 mol% Ag). Addition of only 0.25 mol% of Ag to the nodule decreased the temperature of complete CO oxidation from 350°C to as low as 100°C. This enhanced activity was explained by the concerted action of Ag and Mn, where CO was preferentially adsorbed on Ag2O and oxidized. The reduced Ag was then reoxidized rapidly by oxygen transferred from Mn. The promoting effect of Ag2O on H2O2decomposition and ketonization of acetic acid, however, was less pronounced.

Zirconium Oxides Dispersed on Silica Derived from Cp2ZrCl2, [(i-PrCp)2ZrH(μ-H)]2, and Zr(OEt)4Characterized by X-Ray Absorption Fine Structure and Catalytic Ketonization of Acetic Acid

Newly dispersed Zr oxides on SiO2were prepared from Cp2ZrCl2, [(i-PrCp)2ZrH(μ-H)]2, and Zr(OEt)4precursors and were characterized by X-ray absorption fine structure (XAFS) and catalytic ketonization of acetic acid. ZrCp2Cl2and [(i-PrCp)2ZrH(μ-H)]2precursors yielded monomeric Zr oxides with unsaturated coordination in low loadings, whereas Zr(OEt)4yielded Zr-oxide assemblies in octahedral symmetry independent of Zr loading up to 15 wt% Zr. The former catalysts were more active than the latter catalyst for ketonization of acetic acid. The catalytic ketonization was suggested to proceed via bidentate acetates adsorbed on neighboring Zr sites.

Ketones from monocarboxylic acids: Catalytic ketonization over oxide systems

The ketonization of acetic acid was studied in the presence of a series of 20 oxide catalysts supported on SiO 2, TiO 2 and Al 2O 3. The reactions were performed in the continuous flow reactor. Ceria-and mangania-containing catalysts exhibited the highest activity. The influence of the oxide phase concentration, liquid hourly space velocity and of the type of the catalyst carrier on the acetone yield was determined. Alumina support showed the most pronounced effect on the activity of deposited oxides. High yields of 3-pentanone, 6-undecanone, and 7-tridecanone were achieved in the ketonization of appropriate acids in the presence of mangania and ceria catalysts in large-scale laboratory experiments.

Palladium(II)-catalyzed hydroarylation of α,β-unsaturated aldehydes and ketones with triarylstibines in the presence of silver acetate

Triarylstibines react with α,β-unsaturated aldehydes and ketones in acetic acid at 25°C in the presence of silver acetate and a catalytic amount of palladium(II) acetate to afford the hydroarylation products by conjugate addition in good yields.

ChemInform Abstract: Zinc‐Promoted Reactions. Part 3. The Reduction of α,β‐ Unsaturated Ketones in Acetic Acid.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Ultrasound assisted zinc reactions in synthesis 1. Efficient reduction of enones

Zinc reduction of α, β-unsaturated ketones in acetic acid has been efficiently accomplished under sonochemical conditions. Different α-enone systems give two kinds of products: olefins and allylic alcohols. Regio- and stereoselective are reported.

ChemInform Abstract: The Synthesis of 1‐Aminoalkylphosphonic Acids. A Revised Mechanism of the Reaction of Phosphorus Trichloride, Amides and Aldehydes or Ketones in Acetic Acid (Oleksyszyn Reaction).

AbstractThe Oleksyszyn reaction leads to phosphonic acids of type (VI).

The synthesis of 1‐aminoalkylphosphonic acids. A revised mechanism of the reaction of phosphorus trichloride, amides and aldehydes or ketones in acetic acid (Oleksyszyn reaction)

AbstractThe mechanism of the amidoalkylation of trivalent phosphorus compounds in acetic acid has been reinvestigated. Evidence is presented that 1‐(acylamino)alkyl acetates 5 and not N,N′‐alkylidenebisamides 2 are the intermediates in this reaction. Supporting literature analogies are discussed. This paper also describes a convenient procedure for the preparation of crude (acylamino)alkyl alkanoates 5, which are excellent amidoalkylating agents. The usefulness of these reagents is demonstrated by a simple two‐step “one pot” synthesis of 1‐aminoalkylphosphonic acids 1.

Catalytic activity of the 1:1:1 Zn, Cr and Fe mixed oxide: Mechanistic study of the ketonization of acetic acid

The catalytic activity of a ternary oxide mixture of Zn, Cr and Fe in 1:1:1 atomic concentration has been studied using ketonization of acetic acid. The Arrhenius plot for the reaction shows a break around 673 K indicating the dependence of the reaction mechanism on temperature. Electrical conductance measurement also shows a change in the electronic nature of the catalyst around 673 K. The utilization of dehydration and dehydrogenation active sites of the catalyst for the ketonization process is established by the mutual effect of isopropyl alcohol and acetic acid on each others reaction on the catalyst. Competitive reaction study shows that ketonization follows Langmuir-Hinshelwood mechanism where as esterification follows Rideal-Eley mechanism. Product inhibition studies and infrared spectral studies show that the reaction is between two adsorbed acetate ions above 673 K and between one adsorbed acetate ion and an adsorbed acyl carbonium ion below 673 K.

Synthesis of potential anticancer agents. Pyrido[4,3-b][1,4]oxazines and pyrido[4,3-b][1,4]thiazines.

Hydrolysis of the chloro group of ethyl (6-amino-4-chloro-5-nitropyridin-2-yl)carbamate (3) with formic acid gave the corresponding 4-hydroxypyridine 4. Catalytic hydrogenation of the nitro group of 4 gave the 5-amino-4-hydroxypyridine 5, which was reacted with alpha-halo ketones in acetic acid at room temperature to give a series of 3- and 2,3-substituted ethyl (5-amino-2H-pyrido[4,3-b][1,4]oxazin-7-yl)carbamates 8. Treatment of 8 with hot concentrated hydrochloric acid regenerated the pyridine synthon 5. In the reaction of 3 with thioacetate, the product underwent hydrolysis and air-oxidation to give the corresponding disulfide 6. Simultaneous reduction of both the nitro group and disulfide linkage of 6 gave the 5-amino-4-mercaptopyridine 7, which was reacted with alpha-halo ketones either in acetic acid at room temperature or in a mixture of ethanol and water at reflux to give a series of 3-, 2,3-, and 2,2,3-substituted ethyl (5-amino-2H-pyridol[4,3-b][1,4]thiazin-7-yl)carbamates 9. The effects of these pyridooxazines and pyridothiazines upon the proliferation and the mitotic index of cultured L1210 cells and upon the survival of mice bearing P388 leukemia were determined.

OXIDATIVE CYCLISATION WITH THALLIUM (III) ACETATE: SYNTHESIS OF 3(2H)-BENZOFURANONES

Abstract The reaction of thallium (III) acetate with enolisable o-hydroxy and o-methoxyphenyl ketones in acetic acid gave predominantly 2-acetoxy-3(2H)-benzofuranones.

Mechanism of ketonization of acetic acid on anatase TiO2 surfaces

The interaction of CH3COOH with anatase TiO2 surfaces has been studied and the results analysed in connection with those previously obtained for HCOOH on this and other oxides. The electron-donor properties of the carboxylate species formed at the surface were found to enhance the thermal elimination of surface hydroxyls, thus determining the actual state of the surface under catalytic conditions. Formation of ketene was detected by i.r.; a mechanism, involving this ketene and molecularly adsorbed acid in equilibrium with the gas phase, has been put forward for catalytic ketonization on TiO2 at T 350°C in the absence of gas phase produces alkyl-metal species (Ti—CH3) which, at T > 400°C, give C2H6 and CH4 leading to irreversible coke poisoning of the surface.

Esterification of alcohols with acetic acid over ferric oxide

AbstractFerric oxide has been found to promote both the ketonization of acetic acid and its esterification with methyl alcohol, isopropyl alcohol, and benzyl alcohol. The competitive kinetic technique, where the esterification reaction is made to compete with the ketonization of acetic acid, has been used to elucidate the mechanistic model for the ketonization of acetic acid on iron oxide. The ketonization of acetic acid at 375°C is found to be a second‐order reaction which proceeds through a Langmuir‐Hinshelwood mechanism.

Studies on the ketonization of acetic acid on chromia: I. The adsorbate-catalyst interaction

The ketonization of acetic acid has been studied on a chromia catalyst at 460 °C and at a contact time of 0.7 sec at various partial pressures in presence of tertiary butyl alcohol and benzyl alcohol. There is no inhibition of the ketonization of acetic acid in presence of tertiary butyl alcohol which undergoes only dehydration giving isobutylene and water. Benzyl alcohol, which undergoes only dehydrogenation to give benzaldehyde and hydrogen, suppresses the ketonization of acetic acid. Comparative studies of the reaction of isopropyl alcohol in mixture with acetic acid and also with propionic acid, under identical conditions, confirm the conclusion that the ketonization is caused by the same activity of the catalyst that is responsible for dehydration and dehydrogenation. It is suggested that the ketonization occurs through the interaction of two acetic acid molecules adsorbed on the surface of chromia, one of them utilizing the dehydrogenation activity for adsorption and the other utilizing the dehydration activity.

Catalytic ketonization of acetic acid over mixed catalysts ZrO2-Al2O3

1. The kinetics of the catalytic ketonization of CH3COOH over coprecipitated ZrO2-Al2O3 catalysts were studied by a flow method at 300–370° under conditions of zero order with respect to the reagent. With increasing ZrO2 content in the catalyst, an increase in the catalytic activity is observed. 2. Ketonization of CH3COOH proceeds directly, without intermediate formation of acetic anhydride.

Catalytic ketonization of acetic acid over a mixed CaCO 3Li 2CO 3 catalyst

Catalytic ketonization of acetic acid over a mixed CaCO 3Li 2CO 3 catalyst

Vapor-phase catalytic ketonization of acetic acid over quadrivalent-metal oxides and BeO

Vapor-phase catalytic ketonization of acetic acid over quadrivalent-metal oxides and BeO