2-butanone conductivity

Another attractive commercial route to MEK is via direct oxidation of / -butenes (34—39) in a reaction analogous to the Wacker-Hoechst process for acetaldehyde production via ethylene oxidation. In the Wacker-Hoechst process the oxidation of olefins is conducted in an aqueous solution containing palladium and copper chlorides. However, unlike acetaldehyde production, / -butene oxidation has not proved commercially successflil because chlorinated butanones and butyraldehyde by-products form which both reduce yields and compHcate product purification, and also because titanium-lined equipment is required to withstand chloride corrosion. 

Walker et al. (1993) conducted a cohort mortality study among 7814 shoe-manufacturing workers (2529 males and 5285 females) from two plants in Ohio (United States) that have been in operation since the 1930s. The workers, men and women, were potentially exposed to solvents and solvent-based adhesives. It was thought that toluene may have been a predominant exposure, but a hygiene survey in 1977-79 showed that, in addition to toluene (10 measurements ranged from 10 ppm to 72 ppm [38-270 mg/m3]), there were also 2-butanone (methyl ethyl ketone), acetone, hexane and... 

Attempts to cyclize the keto sulfide (282) with polyphosphoric acid at temperatures greater than 100 °C gave as the major product the 2-isopropyl-3-methylthiophene (284). When the cyclization was conducted at lower temperatures, the thiochromene (283) was the major product. Since 4-phenylthio-2-butanone cyclized to produce a stable thiochromene, the quaternary carbon in (283) which can form a stable carbenium ion (284a)... 

Treatment of 2,3-epoxy -2-methyl -4 butanone with boron iri-fluorido etherate in benzene (Kq. 471) gives a good yidd of 2,2-dimethyl-S-oxobutyraidehyde.6 7 This product can only be formed by niigr.it ion of an acyl group. When rearrangement waa conducted at 230 over alumina, methyl isopropyl ketone was isolated, not 4-methyJpenUi>< 2,3-dione as claimed previously.71 Deformylation appears U occur readily on the surface of the alumina catalyst. 

For most of these operations, isolated dioxirane solutions are more convenient, because simpler work-up procedures are involved. Furthermore, hydrolytically and acid/base-sensitive substrates may be employed, because the reaction is conducted under strictly anhydrous and neutral conditions. Solvents inert toward dioxirane oxidation may be used for dilution purposes in these oxidations, which include acetone, butanone, cyclohexanone, CH2C12, CHC13, CC14, benzene, and CH3CN. Alcohols (except t-BuOH) and ethers normally should be avoided as solvents, because they react slowly with dioxiranes, especially TFD [37]. 

Ironically, species such as (89 M Li) are also the major isomers obtained when unsymmetrical ke-timines are deprotonated with LDA at -78 There is a kinetic preference for deprotonation anti to the substituent on nitrogen. At very low temperatures, deprotonations with LDA occur at the less-substituted carbon atom via the less stable (Z)-imine. Rearrangements then occur to the syn, less-substituted imine, which is in turn alkylated. On the other hand, deprotonations conducted at -23 to 0 C with LDA are faster than imine isomerization and the imine anion mixture composition reflects the ( ) (Z) ratio of the starting imine. Anti-syn imine anion isomerization occurs to give predominately the more-substituted fyn-metallated imine (cf. 90), which then undergoes alkylation. These results are summarized in Scheme 46 using the f-butylimine of 2-butanone as an example. 

Experiments were first conducted with acetic and polyphosphoric acids, and with several concentrations of H2SO4. As expected for a methyl ketone, with 1-phenyl-2-propanone phenylhydrazone use of PPA catalyst resulted in a large variation in isomer ratio (see Table 1). With 3-heptanone the variations resulting from use of different acids were much smaller. Of several active zeolite catalysts tested, H-beta was found to be the most selective heterogeneous catalyst for the synthesis of the linear isomer from 3-heptanone and l-phenyl-2-butanone phenylhydrazones whereas, in contrast, H-Na-Y gave about equal amounts of both isomers. 

BUTANONE (78-93-3) Forms explosive mixture with air (flash point 30°F/—1°C also reported at 16°F/—9°C). Violent reaction with strong oxidizers, aldehydes, nitric acid, perchloric acid, potassium fcrt-butoxide, oleum. Incompatible with inorganic acids, aliphatic amines, ammonia, caustics, isocyanates, pyridines, chlorosulfonic acid. Able to form unstable peroxides in storage, or on contact with 2-propanol or hydrogen peroxide. Attacks some plastics. Flow or agitation of substance may generate electrostatic charges due to low conductivity. 

The most widely used procedure for the preparation of benzo[a]quinolizidin-2-ones and their 3-alkyl derivatives (270) consists of the reaction between 3,4-dihydroisoquinolines and a,/3-unsaturated ketones, with iminium salt (269) as an intermediate <62CB2135>. 4-Dimethylamino-2-butanone derivatives can play the same role as unsaturated ketones, and have the advantage of allowing the reaction to be conducted in aqueous solutions, which facilitates the isolation of the product <69JCS(C)85> (Scheme 56). The yields obtained in the latter case are usually quantitative for 3-substituted benzo[a]quinolizidin-2-ones, but are considerably lower for the unsubstituted system because of the formation of a secondary product (271). Fortunately, this problem may be overcome by modifying the pH and temperature of the reaction medium <88TH822-0l>. 

Analysis and Characterization. Gas chromatography was performed with a Hewlett-Packard model 5880A equipped with capillary columns and a flame-ionization detector. Gel permeation chromatography was performed with a Hewlett-Packard HPLG model 1090A with a refractive index detector. Tacticity determinations were conducted with an F-19 nuclear magnetic resonance (NMR) spectrophotometer (Varian XL-100) at 94.12 MHz for triad analyses (13). Inherent viscosity measurements were performed in 2-butanone at 25.0 °C. 

Gas sensors made from thin films of camphorsul-fonic acid doped polymer were deposited on inter-digitated electrodes. Such sensors show significant changes in electrical conductance upon exposure to carbonyl compounds, such as acetaldehyde, propi-onaldehyde, benzaldehyde, acetone, and butanone. Three-dimensional plots of relative response against... 

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... 

The Heck reaction as another type of palladium-catalyzed cross-coupling reaction was also combined with a subsequent enzymatic ketone reduction. In their initial work, Cacchi et al. [64] conducted a Heck reaction of an aryhodide with butanone in organic media, and used the crude product obtained after removal of the volatile components directly for a subsequent biocatalytic reduction. The ADH turned out to be compatible with this crude product, and the desired aUyhc alcohols were obtained in yields of up to 85% and with >99% ee in all cases. 

The Claisen-Schmidt reaction between benzaldehyde and butanone was conducted in NCW over a temperature range of 250-300°C without the addition of added acid or base. A 10-fold molar excess of 2-butanone to benzaldehyde was used in order to minimize the formation of higher adducts. The results at temperature of 250,275, and 300°C are shown in Figs. 9.54, 9.55, and 9.56, respectively. 

The typical reaction is conducted at temperatures and pressures designed to be as hot as possible while still keeping the butane a liquid. Typical reaction conditions are 150 °C and 55 atm. Side-products may also form, including butanone, ethyl acetate, formic acid, and propionic acid. These side-products are also commercially valuable, and the reaction conditions may be altered to produce more of them where needed. However, the separation of acetic acid from these by-products adds to the cost of the process. 

Many phase transfer processes are conducted in the absence of solvent. The early ester formation reactions, for example, were carried out with solid carboxylate salt in the presence of a mixture of alkyl halide and a small amount of tertiary amine [14a]. (It was not until the efficacy of sodium iodide as a cocatalyst was demonstrated that 2-butanone was added as cosolvent [14b].) In Starks synthesis of alkyl cyanides by direct displacement of halide, no organic cosolvent was present [10]. Numerous other examples are recorded. Nevertheless, it is common to conduct a phase transfer reaction in the presence of an organic solvent or cosolvent, particularly if the substrate is a solid. 

A unique chemical polymerization technique for CP composites is solution evaporative polymerization. To cite an example, Han et al. [III.45] took a solution of FeCl3 (the oxidant) and PVA (the host polymer) in methanol, then added pyrrole monomer thereto. The oxidation potential of the solution, and hence the polymerization, could be changed and controlled via the proportion of FeClj to PVA as well as via evaporation of the solvent, and was optimally ca. +500 mV vs. SCE. Thus, simple casting of a film from this solution yielded P(Py) composite. The percolation threshold, for a saturation conductivity of ca. 10 S/cm, was claimed to be very sharp, at 5 w/w%. A method which appears to be a combination of solution evaporative polymerization and monomer-sorption polymerization is that carried out by Morita et al. [344] A P(Py)/PMMA composite, with nonhomogenous composition (a gradation of PMMA and P(Py) concentrations) was obtained in 0.1 to 10 pm thickness and 10 to 10 S/cm conductivity from combination of 2-butanone solutions of pyrrole, PMMA and benzoic acid with aqueous solutions of potassium persulfate. 

OH group is the same as in methanol (1.35 x 10 cm lUPAC, 2008), reaction of OH radicals with the —OH group in 2-butanol accounts for approximately 2% of the overall reaction. The product studies conducted by Chew and Atkinson (1996) and Baxley and Wells (1998) show that the reaction of OH radicals with 2-butanol proceeds mainly by H-atom abstraction from the tertiary C—H bond (channel 2). The sole fate of the a-hydroxy alkyl radical CH3C(0H)CH2CH3 is reaction with O2 to give 2-butanone in 100% yield ... 

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