Butanone, boiling point

Methyl ethyl ketone MEK (2-butanone) is a colorless liquid similar to acetone, but its boiling point is higher (79.5°C). The production of MEK from n-butenes is a liquid-phase oxidation process similar to that used to... 

Two column plots are more effective if the two stationary phases are very different from each other. If they are of opposite polarity, then the elution order of the analytes in a given sample should be very different (opposite) on the two phases. For example, in the GC separation of a mixture of n-heptane, tetrahydrofuran, 2-butanone, and n-propanol, the elution order on a polar phase like Carbowax is in the order just listed on a nonpolar phase like SE-30, the order is the exact opposite Neither separation follows the boiling point order. 

The boiling point of 2-butanone (80 °C) is significantly higher than the boiling point of diethyl ether (35 °C), even though both compounds exhibit dipole-dipole interactions and have comparable molecular weights. Offer an explanation. 

Problem 14.30. For each of the following pairs of compounds, indicate which compound has the higher value of the property. Explain, (a) Boiling point methyl propyl ether versus butanone, (b) solubility in water methyl propyl ether versus butanone, (c) solubility in water propanal versus butanal, (d) boiling point butanone versus butanal. 

Ans. (a) Butanone has the higher boiling point because ketones (and aldehydes) are more polar than ethers. 

Acetone is the most important commercial ketone, with over 3 billion kilograms used each year. Both acetone and methyl ethyl ketone (2-butanone) are common industrial solvents. These ketones dissolve a wide range of organic matmals, have convenient boiling points for easy distillation, and have low toxicities. 

F1g.4A Effect of stationary phase polarity on a 4-component separation a) Carbowax-20M (polar) (b) DC-200 (nonpolar). Samples and their boiling points (1) /i-heptane (98) (2) tetrahydrofuran (64) (3) 2-butanone (80) (4) /t-propanol (97). Reprinted with permission of the GOW-MAC Instrument Co., Bethlehem, PA, U.S.A. 

A Finkelstein substitution with practical utility was reported some years ago (Fig. 34).130 An co-bromo fatty acid undergoes halogen exchange with radioactive Na 23i to provide the labelled iodo acid, used as a tracer for the medical exploration of cardiac metabolism. The sonochemical reaction conducted in butanone provides quantitative yields of the expensive and thermally labile product, and the presence of water in the solvent, up to 7%, is tolerated. In comparison, the usual method requires heating at ca. 180 C and anhydrous conditions, and the purity of the product is much less satisfactory. It can be noticed that the unusually high temperature of the sonochemical reaction, close to the solvent boiling point, makes an interpretation hazardous. A second case of a Finkelstein substitution, a mesylate-iodine exchange, was published recently without experimental detail. i... 

In the experiment that follows, the hydration of a terminal alkyne is illustrated by the conversion of 2-methyl-3-butyn-2-ol (3) to 3-hydroxy-3-methyl-2-butanone (4), as shown in Equation 11.13. The presence of a hydroxyl group in 3 has little effect on the chemical properties of the carbontriple bond. Rather, the main effect of the polar hydroxyl group is on the physical properties of the molecule, with the boiling point of 3 being considerably higher than those of other acetylenic hydrocarbons having the same molecular weight. 

Basically, the following solvents are used petroleum naptha 60/95, petroleum naptha 80/110, ethylacetate, acetone (dimethylketone), butanone (methylethylketone), toluene (methylbenzene), ethanol, isopropanol, or sometimes tetrahydrofiirane, which is a suitable solvent for PVC. For adhesive storage, key data of the corresponding solvents such as boiling point, flash point, and the rate of evaporation are necessary. O Table 36.1 shows a summary of these data for the solvents mentioned above. (Flash point refers to the lowest temperature at which a volatile liquid can vaporize to form an ignitable mixture in air.)... 

The exposure of humans in the private bathroom or public beauty shops is often underestimated. The major sources of exposure to chloroform (CHCI3) in the United States are showers, boiling water and clothes washers. CHCI3 is formed from the chlorine used to treat water supplies (Ott and Roberts, 1998). Many cosmetic products contain a number of VOCs such as 2-phenoxyethanol, 2-butanone, acetone, terpenes, 2-hydroxy-4-meth-oxybenzophenone or phenylmethanol. However, in most product categories we are not selling a product, we are selling a proposition, as Selinger (1988) pointed out. 

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