Diethyl ketone, reaction

Reaction with Selenium Nucleophiles. The reactions of selenium nucleophiles are similar to those of the sulfur nucleophiles selenophosphates can be aminoaLkylated (135). A dihydroselenazine has been obtained by reaction of diethyl ketone, elementary selenium, and ethyleneimine (136). 

Diethyl Ketone. Diethyl ketone [96-22-0] (3-pentanone) is isomeric with methyl / -propyl ketone (2-pentanone), which has similar solvent and physical properties. Diethyl ketone is produced by the decarboxylation of propionic acid over Mn02—alumina (165), Zr02 (166), or Zr02 or Th02 on Ti02 (167,168). Diethyl ketone can also be produced by the hydrocarbonylation of ethylene (169—171). It is used as a solvent and a reaction intermediate. 

Butyraldehyde undergoes stereoselective crossed aldol addition with diethyl ketone [96-22-0] ia the presence of a staimous triflate catalyst (14) to give a predominantiy erythro product (3). Other stereoselective crossed aldol reactions of //-butyraldehyde have been reported (15). 

With Unsaturated Compounds. The reaction of unsaturated organic compounds with carbon monoxide and molecules containing an active hydrogen atom leads to a variety of interesting organic products. The hydroformylation reaction is the most important member of this class of reactions. When the hydroformylation reaction of ethylene takes place in an aqueous medium, diethyl ketone [96-22-0] is obtained as the principal product instead of propionaldehyde [123-38-6] (59). Ethylene, carbon monoxide, and water also yield propionic acid [79-09-4] under mild conditions (448—468 K and 3—7 MPa or 30—70 atm) using cobalt or rhodium catalysts containing bromide or iodide (60,61). 

This procedure represents a simple and unique route to certain pyran-4-ones. The reaction can be applied also to benzyl methyl ketone and diethyl ketone the corresponding pyran-4-ones are obtained in yields of 48% and 26%, respectively. 

As illustrated in Scheme 3 20 and Table 3-5, using 55a or 55b as the chiral auxiliary,, vy -aldol adduct 56 can be obtained with high stereoselectivity via aldol reaction of diethyl ketone with various aldehydes.39... 

TABLE 3 5. Reaction of Aldehydes with the Enolate from Diethyl Ketone and Bromoborane (R,R)-55b... 

Mixtures of organic solvent and water have also been studied (Scheme 11). hi this context, Watanabe and coworkers studied the catalytic dehydration of fructose to HMF at 150°C in acetone-water mixtures and in the presence of a cation-exchange resin catalyst (Dowex 50wx8-100) [92]. The use of acetone-water (70 30 w/w) as reaction medium resulted in a yield of HMF of 73% at 94% conversion. Moreover, under these conditions, the catalyst was stable for at least five catalytic runs. Assistance of microwave not only increased the selectivity to HMF but also had a beneficial effect on the reaction rate. In this context, Gaset et al. studied the activity of Lewatit SPC-108 (cation-exchange resin) in a mixture of organic solvent (MIBK or diethyl ketone or benzonitrile or butyronitrile or dichlor-oethylether or nitropropane) and water (from 1/7 to 1/12 by volume) at a temperature around 85-90°C Under these conditions, HMF has been obtained with a yield of 70-80% [93, 94]. 

The anion formed from the acetyl methyl group under reaction conditions then attacks one of the carbethoxy groups to form a cylohexanone to give (74-4) as the isolated product. The free acid obtained on hydrolysis of the ester decarboxylates to give the (3-diketone (74-5). In a classic apphcation of the Knorr pyrrole synthesis, the diketone is then allowed to react with 2-aminopentan-3-one. Since the latter is unstable, it is generated in situ by reduction of the nitrosation product from diethyl ketone. There is thus obtained piquindone (74-6) [76], a compound that displays antipsychotic activity. 

Problem 15.49 By rapid test-tube reactions distinguish between (a) pentanal and diethyl ketone, (h) diethyl ketone and methyl n-propyl ketone, (c) pentanal and 2,2-dimethylpropanal, d) 2-pentanol and 2-pentanone. 

The slow combustion reactions of acetone, methyl ethyl ketone, and diethyl ketone possess most of the features of hydrocarbon oxidation, but their mechanisms are simpler since the confusing effects of olefin formation are unimportant. Specifically, the low temperature combustion of acetone is simpler than that of propane, and the intermediate responsible for degenerate chain branching is methyl hydroperoxide. The Arrhenius parameters for its unimolecular decomposition can be derived by the theory previously developed by Knox. Analytical studies of the slow combustion of methyl ethyl ketone and diethyl ketone show many similarities to that of acetone. The reactions of methyl radicals with oxygen are considered in relation to their thermochemistry. Competition between them provides a simple explanation of the negative temperature coefficient and of cool flames. 

High Temperature Reaction. Reaction in the high temperature regime produces carbon monoxide, water, methane, formaldehyde, and methanol (8) the two higher ketones also form ethylene (I). The intermediate responsible for chain branching appears to be formaldehyde. The concentration of formaldehyde and the rate of reaction run parallel over the whole of the reaction, as shown in Figure 4 for diethyl ketone. 

Figure 4. Variation of formaldehyde and rate of reaction throughout the reaction of 40 mm. of diethyl ketone + 40 mm. of oxygen at 400°C. (1)...

The detection of 1,2-propylene oxide in the products from methyl ethyl ketone combustion is particularly interesting. It parallels the formation of ethylene oxide in acetone combustion (8) and of 1,2-butylene oxide in the combustion of diethyl ketone. Thus, there is apparently a group of isomerization reactions in which carbon monoxide is ejected from the transition state with subsequent closing of the C—C bond. Examination of scale molecular models shows that reactions of this type are, at any rate, plausible geometrically. 

Low Temperature Reaction. Reaction in the low temperature regime below 320°C. is of a different character. The products include carbon dioxide and significant quantities of peroxy compounds, as well as carbon monoxide, water, formaldehyde, and methanol, but methane and ethylene are formed only in traces. The peroxy compounds comprise hydrogen peroxide from all three ketones, methyl hydroperoxide from acetone (8) and methyl ethyl ketone (I), and ethyl hydroperoxide from diethyl ketone (1). Methyl ethyl ketone also gives large amounts of peracetic acid (1). 

Figure 6 shows the variation of peroxide concentration in methyl ethyl ketone slow combustion, and similar results, but with no peracid formed, have been found for acetone and diethyl ketone. The concentrations of the organic peroxy compounds run parallel to the rate of reaction, but the hydrogen peroxide concentration increases to a steady value. There thus seems little doubt that the degenerate branching intermediates at low temperatures are the alkyl hydroperoxides, and with methyl ethyl ketone, peracetic acid also. The tvfo types of cool flames given by methyl ethyl ketone may arise from the twin branching intermediates (1) observed in its combustion. 

Aliphatic ketones also undergo photoreduction, as evidenced by the facile photoreduction of acetone in cyclohexane341 and in hexane.342 Aromatic ketones are more commonly associated with the reaction because they do not undergo type I cleavages as readily as aliphatic ketones. As already mentioned, photolysis of diethyl ketone... 

Triethyl carbinol has been prepared by the action of zinc on a mixture of ethyl iodide and diethyl ketone 1 by the action of magnesium on ethyl bromide in diethyl ketone solution 2 as a by-product in the reaction between ethylmagnesium bromide and carbon oxysulfide 3 by the action of ethylmagnesium bromide on ethyl propionate 4 by the action of ethylmagnesium bromide on ethyl chloroformate 5 and by the action of ethyl-magnesium bromide on ethyl cyanoformate.6... 

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