Liquid 2-pentanone

The rates of formation of the main products, at 3130 A, are given in Table 23 (ref. 220). In addition, CO, CH4, CaHg, CH3CHO and n-C HiA were also identified however, their amounts did not exceed 10 % of that of CjHg. At all temperatures investigated, ib The value of rapidly increases with temperature, while (j n and i i are independent of temperature. The quantum yields of primary processes II and III are similar the ratio = 0.45 is independent of tem- 

RATE OF FORMATION OF PRODUCTS FROM LIQUID 2-PENTANONE PHOTOLYSIS (iN 10 MOLE.I .SEC UNITS) AT 3130A AND / = 8xl0 QUANTA.l .SEC  

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Both uncalcined and calcined LDHs have also been shown to be effective supports for noble metal catalysts [18-25]. For example, palladium supported on Cu/Mg/Al LDHs has been used in the liquid phase oxidation of limonene [24], and on calcined Mg/Al LDHs for the one-pot synthesis of 4-methyl-2-pentanone (methyl isobutyl ketone) from acetone and hydrogen at atmospheric pressure [25]. In the latter case, the performance depends on the interplay between the acid-base and hydrogenation properties. More recently. 

Clear, watery, flammable liquid with a mild, pleasant, characteristic odor similar to 2-butanone or the pentanones. Experimentally determined detection and recognition odor threshold concentrations were 1.3 mg/m (270 ppbv) and 5.2 mg/m (1.1 ppmy), respectively (Heilman and Small, 1974). 

Covers, H., Ruepert, C., Stevens, T.]., and van Leeuwen, C.]. Experimental determination and prediction of partition coefficients of thioureas and their toxicity to Photobacterium phosphoreum, Chemosphere, 15(4) 383-393, 1986. Govindarajan, M. and Sabarathinam, P. Effect of some inorganic salts on the ternary liquid-liquid equilibria of the water + 4-methyl-2-pentanone + propanoic or butanoic acid at 35 °C, / Chem. Eng. Data, 42(2) 402-408, 1997. 

Synonyms 2-Pentanone ethyl acetone Physical Form. Colorless liquid Uses. Solvent Exposure. Inhalation... 

DIACETONE ALCOHOL Diacetone, 4-Hydroxy-4-Methyl-2-Pentanone, Tyranton Flammable Liquid, III 1 2 0... 

Diacetone Alcohol. Diacetone alcohol (DAA) (4-hydroxy-4-methyl-2-pentanone) is a colorless, mild smelling liquid which is completely miscible with water and most oiganic solvents. It is the simplest aldol condensation product of acetone, and because of its keto-alcohol functionalies it has special utility in the coatings industry where it is used to dissolve cellulose acetate to give solutions with high tolerance for water (115). 

The McReynolds constants listed are differences in retention index units between die reference compound run on squalane and on die other phases listed. The last entry in the table shows die absolute retention indices for the reference compounds on squalane. Reference compounds are (1) benzene, (2) 1-butanol, (3) 2-pentanone, (4) 1 nitropropane, and (5) pyridine. (Note that Rohrschneider s constants are based on these reference compounds and may differ slightly from the McReynolds constants. The reference compounds for Rohrschneider s constants are (1) benzene, (2) ethanol, (3) 2-butanone, (4) nitromethane, and (5) pyridine.) The minimum temperature is that at which normal gas-liquid chromatography (GLC) behavior is expected. Below that temperature, die phase will be a solid or an extremely viscous gum. The maximum temperature is that above which die bleed rate will be excessive. 

Bromopyridine (3.16 g, 20 mmol) is added to an enolate solution prepared from 8.56 g (75 mmol) of 2,4-dimethyl-3-pentanone and 4.12 g (75 mmol) of KNH2 in 300 mL of liquid ammonia. After the mixture has been irradiated for 1 h, diethyl ether is added and the ethereal suspension remaining after evaporation of the ammonia is decanted through a filter and the residual salts are washed with diethyl ether. This reaction affords high yield of the substitution product (Sch. 37). 

The photostimulated reaction of 2-bromo-3-f-propoxypyridine (278) and ketone enolate ions in liquid ammonia afforded the substitution products 279, which gave quantitatively the furo[3,2-6]pyridines (280) (equation 173). With 2-pentanone enolate ion, 278... 

The parameter values are subsequently averaged to produce a panel stimulus curve. Apparently, the pentanone is depleted from the liquid layer in the mouth very rapidly. It should be borne in mind that this is not only due to release into the gas phase, but must also be ascribed to uptake into the mouth and upper airways (3). 

Dehydrogenation of 1,4-pentanediol over a copper chromite catalyst in the liquid phase yields the corresponding hydroxy ketone, 5-hydroxy-2-pentanone (30%). ... 

Among the products of the radiolysis of 2-pentanone and 2-hexanone, ethylene and propene were found in considerable amounts . The distribution of the butenes in the radiolysis of 4-methyl 2-hexanone (both in the vapour and in the liquid phase) was very much similar to that observed in fhe photolysis at short wavelengths . 

Vinylpyrazine undergoes a Michael condensation with cyclohexanone, cyclo-pentanone, and acetophenone for example, 2-vinylpyrazine with cyclohexanone and sodium gave 2-[2 -(r -oxocyclohexan-2"-yl)ethyl]pyrazine, and with acetophenone and sodamide in liquid ammonia gave low yields of 2-(3 -benzoylpropyl)pyrazine (monopyrazylethylation) and the bis Michael adduct (731). 

The first report on the reduction of a carbonyl substituted cyclopropane was published in 1949. Reactions of methyl cyclopropyl ketone (131) with sodium in liquid ammonia in the presence of ammonium sulfate yielded instead of the expected methyl cyclopropylcarbinol (132) only a mixture of 2-pentanone (133) and 2-pentanol (134). 

Then, 3000 mL. of 4-methyl-2-pentanone was added, and 1030.0 g (16.9 mol) of 28% by weight aqueous ammonia was gradually added to the mixture while maintaining the liquid temperature to -10 to 5° C. to effect neutralization. After the neutralization, the mixture was heated to 80° C., and 3,4-methylenedioxymandelic acid was extracted in a 4-methy]-2-pentanone layer (an organic solvent layer). At this time, the reaction mixture was separated into two layers of an organic solvent layer and an aqueous layer. 

After completion of the reaction, the mixture was cooled to 25° C., 140 mL. (1.00 mol) of a 25% by weight aqueous sodium hydroxide solution was added to the mixture to make up the whole reaction mixture weak basic (pH=7.9). Subsequently, 4-methyl-2-pentanone layer (an organic solvent layer) and an aqueous layer were separated, and the organic solvent layer was analyzed by gas chromatography, then no l,2-methylenedioxy-4-nitrobenzene which is a by-product was detected. Also, when it was analyzed by high performance liquid chromatography, a conversion of 1,2-methylenedioxybenzene was 97%, and a yield of piperonal was 78% (in terms of mole). 

There have been numerous reports on the reduction of activated cyclopropanes with alkali metals either dissolved in liquid ammonia or used in suspension. Most of these reactions were carried out with lithium as reducing agent. In an early study, various substituted cyclopropyl ketones were treated with lithium in liquid ammonia. rranj-l-Acetyl-2-methylcyclopropane (1, R = Me = H R = Me) gave 3,4,4-trimethyl-2-pentanone (3) as the result of... 

Figure 17.8 summarizes H, C m and F for mixtures of cyclohexane with 1,4-dioxane (a cyclic diether, C4H802) (curve 1), and oxane11 (a cyclic ether, C5H10O) (curve 2). The values of H, and C m for the oxane system are typical of those for a (polar + nonpolar) mixture, with a maximum of approximately 450 J-mol-1 and small C m, and FFor the 1,4-dioxane system, however, H and are very large, with maxima in excess of 1600 J-mol-1 for H and 1000 J-mol-1 for GJj,. F is also large, with a maximum of nearly 1 cm3-mol-1. Of special interest is the double minimum in Cp m as a function of x2 for this system, as shown in Figure 17.1 Od. These so-called W heat capacity curves are unusual, but not uncommon. They occur in mixtures of a normal or cycloalkane with certain chemically dissimilar liquids. Saint-Victor and Patterson12 have summarized a number of these systems, which include as the second component (in addition to 1,4-dioxane), trioxanonane, 2-butanone, 3-pentanone, 1,2-dichloroethane, 1,4-dichloro-butane, and tetraoxadodecane. Associated with each W -shaped C m curve are large HG% and F maximum values.

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