Acetone, in water

In general, peroxomonosulfates have fewer uses in organic chemistry than peroxodisulfates. However, the triple salt is used for oxidizing ketones (qv) to dioxiranes (7) (71,72), which in turn are useful oxidants in organic chemistry. Acetone in water is oxidized by triple salt to dimethyldioxirane, which in turn oxidizes alkenes to epoxides, polycycHc aromatic hydrocarbons to oxides and diones, amines to nitro compounds, sulfides to sulfoxides, phosphines to phosphine oxides, and alkanes to alcohols or carbonyl compounds. 

There are, however, a number of well-known systems in which heat effects definitely cannot be ignored. Examples include absorption of ammonia in water, dehumidification of air with concentrated H9SO4, absorption of HCl in water, and absorption of SO3 in H9SO4. Another interesting example is the absorption of acetone in water, in which the heat effec ts are mild but not neghgible. 

FIG. 14-8 Design diagram for adiabatic absorption of acetone in water. Example 6. 

Gmehhng and Onken (op. cit.) give the activity coefficient of acetone in water at infinite dilution as 6.74 at 25 C, depending on which set of vapor-liquid equilibrium data is correlated. From Eqs. (15-1) and (15-7) the partition ratio at infinite dilution of solute can he calculated as follows ... 

From acetone in water and concentrated hydrochloric acid by addition of bromine. Hughes, Watson, and Yates, J. Chem. Soc. 1931, 3322. 

Equation describes the total vapor pressure above a solution when the solute does not have a significant vapor pressure of its own. In other words, Raoulfs law applies only to nonvolatile solutes. When the solute is volatile, such as for a solution of acetone in water, the total vapor pressure above the solution is a sum of contributions from both solvent and solute. 

The reaction of 1,2,3-triazolium-l-aminides 3 with propiolate esters led to fluorescent 2,5-dihydro-1,2,3-triazine derivatives 4 in one pot, involving a Huisgen cycloaddition followed by a sequence of rearrangements <06JOC5679 06TL1721>. These reactions can be carried out in acetone, in water, or under solvent-free conditions. 

Applications of TDDFT within the QM/M M Framework -Solvent Shift of the So/St Transition of Acetone in Water... 

Fig. 1.5 Acetone in water. The QM region is shown as thick cylinders, the MM region as thin sticks.

This method may be particularly useful for detecting small extents of hydration, for example for acetone, which is normally regarded as unhydrated. Preliminary measmements by Hine and Redding (1964) of the N.M.R. spectrum at 60 Mc/s of a 20% solution of acetone in water (H2O or D2O) show a weak signal 48 c/s upheld from that due to acetone. The attribution of this signal to Me2C(OH)2 is confirmed by the fact that... 

Next, place 0.5% acetone in water in reservoir A and water in reservoir B. 

Oppenauer-type oxidation of secondary alcohols can be a convenient procedure for obtaining the corresponding carbonyl compounds. It was found recently [19], that Ir(I)- and Rh(I)-complexes of 2,2 -biquinoline-4,4 -dicarboxylic acid dipotassium salt (BQC) efficiently catalyze the oxidation of secondary alcohols with acetone in water/acetone 2/1 mixtures (Scheme 8.5). The reaction proceeds in the presence of Na2C03 and affords medium to excellent yields of the isolated ketones. The process is much faster in largely aqueous solutions, such as above, than in wet organic solvents in acetone, containing only 0.5 % water, low yields were observed (15 % vs. 76 % in case of cyclohexanol). 

Ten grams of Sepharose are sucked off on a sintered-glass funnel. First wash with 3 vol. water, then with 3 vol. 30% acetone in water (v/v), and then with 3 vol. 60% acetone (v/v) in water. Suspend the gel in 10 ml of 60% acetone and cool to 0 °C. Add the needed amount CDAP dropwise (cf. Table 3.9) followed by the respective amount of triethylamine (TEA) to the stirred gel suspension. Suck off the gel after 2 min and wash with a tenfold volume of Soln. D. The activated gel is stable for 1 h. 

There is no detectable common bromide ion inhibition of the reaction of tert-butyl bromide in 90% acetone in water, " " or common chloride ion inhibition of the reaction of 5-Cl in 50 50 (v/v) water/trifluoroethanol or... 

Figure for Exercise 18-E. Infrared absorption spectra ot 10-50 vol% acetone in water. Vertical arrow shows corrected absorbance for 50 vol% acetone, which is obtained by subtracting baseline absorbance from peak absorbance. [Spectra from A. Atran, ftir Absorbance linearity ol Square Column Attenuated Total Reflectance, Am. Leri). February 1993, p. 40MMM.]... 

Extract the chlorophyll from the chloroplasts by mixing, in a conical centrifuge tube, 0.05 mL of well-mixed chloroplast suspension with 9.9 mL of 80% acetone in water. Spin in a tabletop centrifuge for 10 minutes. Transfer the supernatant to a glass cuvette and read the absorbance at 652 nm using 80% acetone in water as reference. Calculate the concentration of chlorophyll in the chloroplast suspension using Equation E9.3. 

The measurement of cured meat pigment concentration is based on the A540 of the nitrosyliron(II)protoporphyrin group (also known as nitrosylheme or NO-heme mol. wt. 646) in an extraction solution of 80% (final) acetone in water, taking into consideration the 70% water content of the meat sample. Hornsey (1956) established that only the pink NO-heme was extracted in 80% acetone. Heme groups from fresh meat pigments (Table F3.2.1) are not extractable in 80% acetone. However, upon acidification with hydrochloric acid, NO-heme in 80% acetone was completely oxidized to hemin. Thus, NO-heme concentrations could be expressed in equivalent ppm hemin. 

The system described forms the basis of the two-film theory. Because of the mutual solubility of acetone in water, the rate at which molecules of acetone move through the liquid film is large. Consequently, acetone molecules in the air that approach the liquid film are removed at such a fast rate that the concentration of acetone in the air film becomes less than it is in the main body of gas. This concentration gradient between the air film and main air body supplies the main driving force for the transfer of mass. 

The column is eluted by gradient elution the concentration of acetone in water increases almost linearly from 0 to 95%. Gibberellins A8, Alf A6, and A5 were eluted with the following percentages of acetone in water 27 to 38, 38 to 41, 43 to 49, and 51 to 56%, respectively. The gibberellins are obtained pure after further chromatography on a column of silicic acid and Celite, followed by crystallization. 

Approximately 2 liters of viscous endosperm extracted from immature seed was adjusted to pH 3 by the addition of sulfuric acid. This suspension was extracted directly several times with ethyl acetate. Most of the biologically active material was removed to the ethyl acetate phase, as determined by bioassay with dwarf mutants of maize (8). The combined extracts were concentrated and extracted in turn with 5% aqueous sodium carbonate solution to remove acidic substances. All the biologically active material was removed to the aqueous phase. After this fraction had been acidified to pH 3, it was again extracted with ethyl acetate, which removed the biologically active substances to the ethyl acetate phase. The residue from the ethyl acetate layer (2.5 grams) was then chromatographed on a charcoal-Celite (1 2) column developed with increasing concentrations of acetone in water. 

Fractions brought off the column with elutants ranging from 80% acetone in water to pure acetone (108 mg. of solids) contained most of the biologically active material. The solids in these fractions showed a yellow fluorescence when dissolved in concentrated sulfuric acid. Gibberellic acid (V) shows a similar fluorescence under these conditions, whereas gibberellin A4 and other fungal gibberellins do not. 

In short, our S-MC/QM methodology uses structures generated by MC simulation to perform QM supermolecular calculations of the solute and all the solvent molecules up to a certain solvation shell. As the wave-function is properly anti-symmetrized over the entire system, CIS calculations include the dispersive interaction[35]. The solvation shells are obtained from the MC simulation using the radial distribution function. This has been used to treat solvatochromic shifts of several systems, such as benzene in CCI4, cyclohexane, water and liquid benzene[29, 37] formaldehyde in water(28, 38] pyrimidine in water and in CCl4(31] acetone in water[39] methyl-acetamide in water[40] etc. 

Trace acetone in water may be determined by a fast HPLC method (Takami et al., 1985) aqueous sample passed through a cartridge packed with a moderately sulfonated cation-exchange resin charged with 2,4-dinitrophenylhydrazine (DNPH) DNPH derivative eluted with acetonitrile and analyzed by HPLC with a 3-mm ODS column. 

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