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The catalytic activities of maghemite on the aldol condensation of acetone and on the retro-aldol condensation of diacetone alcohol are found to be higher than those of hematite. Further, the catalytic activity of maghemite on the formation of mesityl oxide is significantly higher than that of hematite. The active sites are considered to be surface hydroxyl groups which behave as a Bronsted base and acid points. Maghemite has more basic surface hydroxyl groups than does hematite, and far more acidic surface hydroxyl groups than does hematite they are sufficiently strong to make its average surface acidity greater than that of hematite. The basic surface hydroxyl groups of maghemite are speculated to be those which bond to the iron ions of the octahedral sites the acidic ones are those of the tetrahedral sites of the spinel lattice of the surface.

A method has been proposed for the extraction of bismuth(III) at microgram level from bromide media using mesityl oxide as an extractant. The bismuth–bromo complex formed in the concentration range of 0.05–0.3 mol dm−3 hydrobromic acid showed quantitative extraction into mesityl oxide. Various experimental conditions such as acid concentration, mesityl oxide concentration, period of equilibration, stripping agents, and diverse ions have been studied. Bismuth ion after stripping is determined by thiourea spectrophotometrically. The method is applicable to the analysis of pharmaceutical samples, alloy samples, and synthetic mixtures.

The ion/molecule reactions in acetone were investigated which were induced by the electron impact. It was found that the protonated acetone reacts with an acetone molecule to produce the protonated diacetone alcohol (4-hydroxy-4-methyl-2-pentanone) and the protonated mesityl oxide (4-methyl-3-penten-2-one) through the aldol condensation reaction. It was also found that the acetone molecule isomerizes from keto to enol form in the interaction with the chloride ion. The thermochemical data for the higher-order clustering reactions of the proton and chloride ion with acetone molecules were obtained.

フェノールとアセトンとが反応してビスフェノールAを生成するときには,アセトンがフェノールのパラ位を攻撃している。これに対し,フェノールとメシチルオキシドが反応して4-(4-ヒドロキシフェニル)-2,2,4-トリメチルクロマンを生成するときには,メシチルオキシドがフェノールの酸素を攻撃している。これら二つの求電子試薬のフェノールに対する攻撃位置の違いを明らかにするため,求電子試薬の秀子軌道をHMO法で求めて量子化学的な考察を行なった。これらの求電子試薬はフェノールのパラ位と酸素の両方を攻撃していると考えられる。アセトンがフェノールの酸素を攻撃する反応は可逆であり,生成物もさらに他の化合物に変化するのに対し,フェノールのパラ位を攻撃する反応は不可逆なのでビスフェノールAを生成すると思われる。一方,メシチルオキシドがフェノールの酸素を攻撃して生成する中間体は不可逆な環化反応が起こるのでこの方向に反応が進む。さらに他の原因としてメシチルオキシドの攻撃する炭素とカルボニル基の炭素のLUMOの位相がフェノールの酸素とオルト位の炭素のHOMOの位相とそれぞれ合っていることがあげられる。

Selective asymmetric reductions of carbonyl functionalities in α,β-unsaturated carbonyl compounds, such as β-ionone, 2-methylcyclohexenone and mesityl oxide, were successfully carried out using dihydrosilane-chiral rhodium(I) complex catalyst combinations.

A phenylchromium complex CrPh(acac)2 (1) (acac=2,4-pentanedionato ligand) was prepared from Cr(acac)3 and AlPh3·Et2O. Complex 1 reacts with acetone to give benzene, 2-phenyl-2-propanol, and mesityl oxide and is converted into a hydroxo complex [Cr(OH)(acac)2]2. The mechanism involving the insertion of the carbonyl group of acetone into the Ph–Cr bond giving an alkoxo intermediate is proposed. Reactions of 1 with esters proceed similarly to give diphenylmethanol derivatives and alkoxochromium complexes. Complex 1 reacts with ROH to give benzene and alkoxo complexes [Cr(OR)(acac)2]n [n=1 or 2) which were characterized by means of IR spectra, elemental analyses, molecular weight measurements, magnetic susceptibilities, and chemical reactions. The reactions of 1 with β-dicarbonyl compounds yield corresponding mixed chelate complexes Cr(β-dic)(acac)2, where β-dic=diethyl malonato and 1-ethoxy-1,3-butanedionato ligands.

The kinetics of the direct catalytic conversion of acetone and hydrogen into methyl isobutyl ketone (MIBK) were investigated in the liquid phase using palladium–zirconium phosphate as a catalyst. Kinetic studies on the conversion of acetone into mesityl oxide (4-methyl-3-pentene-2-one) and its hydrogenation were separately carried out using the same catalyst. It was found that the direct reaction proceeded via a sequence of processes: mesityl oxide was first formed by condensation of acetone on acid sites of the catalyst and MIBK was then produced by hydrogenation of the mesityl oxide on palladium metal in the catalyst. Moreover, the experimental results were well interpreted by assuming that the condensation of acetone was controlled by a surface reaction between the acetone molecules adsorbed on the catalyst surface and that the rate of hydrogenation of mesityl oxide was determined by a surface reaction between dissociated hydrogen atoms and adsorbed mesityl oxide molecules.

The sequential separation of osmium and ruthenium as thiocyanate complexes by extraction into mesityl oxide and cyclohexanone is described. The conditions for their re-extraction prior to determination from the respective organic layers have been established. Alternatively, the amounts of osmium and ruthenium were established spectrophotometrically from the coloured mesityl oxide and cyclohexanone layers respectively. The developed procedure has been applied to the separation of these metals present in synthetic samples of various minnerals.

The thioderivative of 2-thenoyltrifluoroacetone [1,1,1-trifluoro-4-(2-thienyl)-4-mercaptobut-3-en-2-one (STTA)] is used for the simultaneous extraction and direct photometric determination of zinc. About 68 μg of zinc was quantitatively extracted at pH 7–7.5 with 10 ml of 0.001 M STTA in carbon tetrachloride as yellow green colored complex. It was measured spectrophotometrically at 450 nm. The system conformed to Beer’s law over the concentration range of 0.4 to 30 μg of zinc per ml. The color of the complex was stable for more than 96 hr. Zinc was extracted quantitatively and was determined in the presence of large excess of (1 : 300) ions which are associated with it. The method was made selective by using sequestering agents like ascorbic, oxalic, citric acids or alkali cyanide to form unextractable negatively charged complexes. The selective extraction with mesityl oxide was used to eliminate the interferences due to iron and chromium. The procedure was found to be applicable for the analysis of zinc ...

Styrene, mesityl oxide, benzonitrile and nitrobenzene are reduced when heated with primary alcohols, such as methanol, ethanol, 1-butanol and benzyl alcohol, in the presence of nickel catalysts. On the other hand, aldehydes are obtained by the dehydrogenation of the primary alcohols. The relative reactivity of the functional groups for the reduction is as follows: C=C>C≡N>NO2>C=O. The carbonyl group and the benzene nucleus can not be reduced under these reaction conditions. A selective reduction occurs in the reaction with mesityl oxide. The lower limit of the reaction temperature depends on the combination of the two species of the hydrogen donor (primary alcohol) and the acceptor compounds. The use of a large excess of alcohols for the reduction is effective in this redox reaction. In the reaction between styrene and benzyl alcohol, the ratio of the decreased amount of styrene to the increased amount of ethylbenzene is always 1 : 1, as determined by gas chromatographic analysis.

Hydrogenation activity of the Raney nickel catalyst for carbonyl compounds was greatly diminished, when the catalyst was treated with a solution of amino acid. On the other hand, no appreciable change in its hydrogenation activity for C=C double bonds occurred upon this treatment. When mesityl oxide was used as a substrate, selective hydrogenation was most clearly demonstrated. The effect of conditions of modification, such as concentration of the modifying solution, immersion time and kind of modifying reagent on the activity of the modified catalyst, were investigated.

The photochemical reaction of mesityl oxide oxime was investigated. In protic solvents, the reaction via oxaziridine proceeded, while in aprotic solvents, syn-anti isomerization was the main reaction pattern. A cyclobutanol formation, which is a new type of reaction in the oxime system, was observed. The photochemical reactions on some other ketoximes and their derivatives were also investigated.

The thio derivative of 2-thenoyltrifluoroacetone 1,1,1-trifluoro-4-(2-thienyl)-4-mercaptobut-3-en-2-one (STTA) is used for the simultaneous extraction and direct colorimetric determination of lead. About 100 μg of lead is quantitatively extracted, at pH 6.5, with 10 ml of 0.0020M STTA-CCl4 as a bright orange colored complex, which can be measured spectrophotometrically at 480 nm. The system conforms to Beer’s law over the concentration range of 1–40 μ/ml of lead(II). The color of the complex is stable for 60 hr. Lead can be quantitatively extracted and determined in the presence of a number of ions. The method is made selective by using some sequestering agents and carrying out selective extractions with mesityl oxide. The procedure is found to be suitable for the analysis of lead in gun metal and solder.

It was found that various organic compounds were reduced in good yields by refluxing them with precipitated metals in water. Water was proved to be indispensable as a hydrogen donor. The reduction of compounds which are insoluble in water was facilitated by using a mixture of dioxane and water. It is of interest that the reduction of nitriles with this catalyst afforded the hydrochlorides of the corresponding primary amines. The results imply the participation of the chloride ion on the ppt-metal catalyst. A selective reduction of C=C was observed in some α,β-unsaturated ketones, such as mesityl oxide and 1,3-diferrocenyl-2-buten-1-one. The relative activity of the various precipitated metals depends not only upon the kinds of the metals but also upon their combination. It is assumed that the surface of the ppt-Ni is acidic as a result of the coexisting chloride ion, which might participate in the catalytic reaction.

The C=O stretching frequencies in acetone, mesityl oxide, acetophenone and benzophenone were measured in various solvents and the frequency shifts induced by solvents were interpreted by McRae’s theoretical equation. Results show that the observed shifts can be explained in terms of the cooperating interactions between solute and solvent molecules. Next, the intensity of the C=O group vibration bands of these ketones was observed and compared with bond moment derivatives calculated by diatomic molecular appoximation. Small changes of about 1 D/A were observed for polar and nonpolar solvents. The increase of the bond moment derivative value in a hydrogen bonding system was attributed to the charge transfer force.

Low temperature cresol No. 1 has an offensive smell, and its spontaneous coloration is remarkable. It was treated with an oxidizing agent and active clay for the purpose of refining, and then washed with sodium bicarbonate solution in order to remove carboxylic acids which give a strong peculiar smell. Refined cresol which has no more offensive smell and shows a little spontaneous coloration, was obtained. The impurities in the low temperature cresol No. 1 and in the refined cresol were measured, and it was found that in the refined cresol every impurity was decreased; especially unsaturated carboxylic acids, carbonyl compounds and basic oil were diminished. In the strong acid oil were detected, propionic, iso-butyric, n-butyric, iso-valeric, n-valeric acids and catechol, in the weak acid oil, p-cresol, 2,4- and 2,5-dimethylphenols, in the neutral oil, n-propyl methyl ketone, mesityl oxide, n-amyl methyl ketone, iso-butyl methyl ketone, o-hydroxybenzaldehyde, benzaldehyde, 4-methylcyclohexanone, acetophen...

γ-Methyl groups of mesityl oxide (I), dypnone (II), 2-isopropylidenecyclopentanone (III), and pulegone (IV) were deuterated by ultra-violet irradiation in methanol-d. It has been claimed that these...

Thermal or photochemical decomposition of ethyl azidoformate in mesityl oxide or in methyl crotonate afforded the corresponding aziridines. Thermal C–C bond cleavage of aziridine-1-carboxylates thus obtained is described.

Dihydrojasmone was easily synthesized by bromination of 4-methyl-3-pentyl-4-penten-2-one, which was obtained by the alkylation of mesityl oxide, followed by the treatment with a base.

Dienol silyl ethers of various 2-cyclohexenones reacted with 4-methyl-3-penten-2-one(mesityl oxide) or methyl acrylate in the presence of Lewis acid to give bicyclo[2.2.2]octanes in moderate yields.