Ketones from carboxylic acids over supported magnesium oxide and related catalysts

Sugiyama, Shigeru; Sato, Kiyozumi; Yamasaki, Seiji; Kawashiro, Katsuhiro; Hayashi, Hiromu

doi:10.1007/bf00764227

Cited by 38 publications

(27 citation statements)

References 6 publications

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“…It is therefore not surprising that the ketonization reaction is well known on polycrystalline oxide samples, and numerous oxides have been found to be active for this reaction. These include γ -Al 2 O 3 [17], ThO 2 [18,19], UO 2 [18], MgO [20], Bi 2 O 3 [17,21], Fe 3 O 4 [22], Fe 2 O 3 [22,23], TiO 2 [17,[23][24][25], Cr 2 O 3 [26], ZrO 2 [23,27], and PbO 2 [17]. Different mechanisms for the ketonization of carboxylic acids have been proposed and debated so far [2]:…”

Section: Introductionmentioning

confidence: 99%

Ketonization of acetic acid on titania-functionalized silica monoliths

Martinez

Huff

Barteau

2004

Journal of Catalysis

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Section: Introductionmentioning

confidence: 99%

Ketonization of acetic acid on titania-functionalized silica monoliths

Martinez

Huff

Barteau

2004

Journal of Catalysis

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“…In such a decarboxylative cross-ketonisation, the carboxylate groups would predefine the position of bond formation, potentially allowing a selective synthesis of any desired regioisomer. If mediated by catalytic amounts of an inexpensive metal with high selectivity for hetero-over homocoupling, the overall process would be advantageous both from economical and ecological standpoints.The decarboxylative homoketonisation of aliphatic carboxylic acids is an established strategy for the preparation of symmetrical dialkyl ketones or cyclic alkanones.[9] State-of-the-art protocols involve gasphase transformations at temperatures above 350 8C at solid catalysts, for example, CaO, ZnO, MgO, [10] TiO 2 , [11] ZrO 2 , [12] MnO, [13] Fe 2 O 3 , [14] or rare earth metal oxides [15] on SiO 2 -, Al 2 O 3 -, or pumice-based supports. However, if equimolar mixtures of aromatic and aliphatic carboxylic acids are subjected to the above catalysts, dialkyl and aryl alkyl ketones are obtained at best in a 1:1 ratio, using elaborate reaction technology such as gas-phase reactions above 400 8C, [16] or continuous-flow reactors.…”

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confidence: 99%

Catalytic Decarboxylative Cross‐Ketonisation of Aryl‐ and Alkylcarboxylic Acids using Magnetite Nanoparticles

2010

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In the presence of catalytic amounts of magnetite nanopowder, mixtures of aromatic and aliphatic carboxylic acids are converted selectively into the corresponding aryl alkyl ketones. As byproducts, only carbon dioxide and water are released. This catalytic cross-ketonisation allows the regioselective acylation of aromatic systems and, thus, represents a sustainable alternative to FriedelCrafts acylations.Keywords: aryl alkyl ketones; catalysis; cross-ketonisation; decarboxylation; iron Aryl alkyl ketones are among the most important synthons in the industrial manufacture of commodities, [1] fine chemicals, and pharmaceuticals.[2] Simple derivatives, at early stages of the chemical value creation chain, are synthesised almost exclusively via FriedelCrafts acylation of arenes, because the low cost of this reaction is unrivalled to date.[3] However, two main issues are associated with this approach. Its low regioselectivity leads to the co-manufacture of large amounts of isomeric by-products, and the use of acyl chlorides as starting materials activated with superstoichiometric amounts of salt mediators (e.g., AlCl 3 ) is responsible for the formation of enormous quantities of salt waste.Regioselective and less waste-intensive acylations, e.g., cross-couplings [4] of sensitive arylmetal reagents with either preformed [5] or in situ-generated [6] carboxylic acid derivatives are widely used to access highervalue synthetic intermediates. However, their high cost precludes their application in the manufacture of base chemicals. This is also the case for alternative approaches, such as Heck-type reactions, [7] or the Pdcatalysed decarboxylative cross-coupling of a-oxocarboxylate salts with aryl halides.[8] Thus, a clear need remained for a broadly applicable, regioselective and waste-minimised aryl alkyl ketone synthesis starting from simple, inexpensive, and widely available chemicals.As a solution to this long-standing problem, we envisioned a catalytic process in which an aromatic and an aliphatic carboxylic acid are cross-coupled under release of CO 2 and water, to selectively give the aryl alkyl ketone (Scheme 1). In such a decarboxylative cross-ketonisation, the carboxylate groups would predefine the position of bond formation, potentially allowing a selective synthesis of any desired regioisomer. If mediated by catalytic amounts of an inexpensive metal with high selectivity for hetero-over homocoupling, the overall process would be advantageous both from economical and ecological standpoints.The decarboxylative homoketonisation of aliphatic carboxylic acids is an established strategy for the preparation of symmetrical dialkyl ketones or cyclic alkanones.[9] State-of-the-art protocols involve gasphase transformations at temperatures above 350 8C at solid catalysts, for example, CaO, ZnO, MgO, [10] TiO 2 , [11] ZrO 2 , [12] MnO, [13] Fe 2 O 3 , [14] or rare earth metal oxides [15] on SiO 2 -, Al 2 O 3 -, or pumice-based supports. However, if equimolar mixtures of aromatic and aliphatic carboxylic acids ar...

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“…They propose a process by which two molecules of acetic acid are coupled to produce acetone, m/z = 58, liberating CO2 and water. This ketonization reaction has been shown to occur on a variety of metal oxides, including alumina [17] and MgO [18]. In a poster presented at the European fire retardancy meeting in 2009, Stec and Hull also reported the formation of acetone from the thermal degradation of an EVA nanocomposite; this was characterized by infrared spectroscopy [19].…”

mentioning

confidence: 99%

EVA-layered double hydroxide (nano)composites: Mechanism of fire retardancy

Wang

Rathore

Songtipya

et al. 2011

Polymer Degradation and Stability

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Abstract:Composites of ethylene-vinyl acetate copolymer with two different layered double hydroxides have been obtained by melt blending and these have been characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis, thermogravimetric analysis connected to mass spectroscopy and cone calorimetry. There is some small difference in dispersion between the zinc-containing and the magnesiumcontaining layered double hydroxides in EVA, but both these are microcomposites with good dispersion at the micrometer level and relatively poor dispersion at the nanometer level. There is a good reduction in the peak heat release rate at 10% LDH loading. In addition to chain stripping, which involves the simultaneous loss of both acetate and a hydrogen atom, forming acetic acid, and the formation of poly(ethylene-co-acetylene), side chain fragmentation of the acetate group also occurs and may be the dominant pathway of thermal degradation in the first step. The presence of the LDH causes acetone, rather than acetic acid, to be evolved in the initial step of the degradation.

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Ketones from carboxylic acids over supported magnesium oxide and related catalysts

Cited by 38 publications

References 6 publications

Ketonization of acetic acid on titania-functionalized silica monoliths

Ketonization of acetic acid on titania-functionalized silica monoliths

Catalytic Decarboxylative Cross‐Ketonisation of Aryl‐ and Alkylcarboxylic Acids using Magnetite Nanoparticles

EVA-layered double hydroxide (nano)composites: Mechanism of fire retardancy

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