Ketone, diisobutyl

Me2C = CHCOCH= CMca- Yellow liquid having a camphor-like odour m.p. 28 C, b.p. 198-5°C. It is formed when propanone is saturated with HCl and allowed to stand. Resembles camphor in many of its properties and is a solvent for cellulose nitrate. Used to prepare diisobutyl ketone (reduction). 

A yield of about 95% of theoretical is achieved using this process (1.09 units of isopropyl alcohol per unit of acetone produced). Depending on the process technology and catalyst system, such coproducts as methyl isobutyl ketone and diisobutyl ketone can be produced with acetone (30). 

Acrylic Acid Recovery. The process flow sheet (Fig. 3) shows equipment and conditions for the separations step. The acryUc acid is extracted from the absorber effluent with a solvent, such as butyl acetate, xylene, diisobutyl ketone, or mixtures, chosen for high selectivity for acryUc acid and low solubihty for water and by-products. The extraction is performed using 5—10 theoretical stages in a tower or centrifiigal extractor (46,61—65). 

MIBK is a flammable, water-white Hquid that boils at 116°C. It is sparingly soluble in water, but is miscible with common organic solvents. It forms an a2eotrope with water as shown in Table 2. Condensation of MIBK with another methyl ketone can produce ketones containing 9—15 carbons. For example, condensation with acetone produces diisobutyl ketone, and self-condensation of two MIBK molecules produces 2,6,8-trimethyl-4-nonanone [123-17-1]. Condensation with 2-ethylhexanal gives 1-tetradecanol (7-ethyl-2-methyl-4-undecanol), avaluable surfactant intermediate (58). 

The one-step route from 2-propanol coproduces diisobutyl ketone and acetone, and is practiced in the United States by Union Carbide (61). The details of a vapor-phase 2-propanol dehydrogenation and condensation process for the production of acetone, MIBK, and higher ketones have been described in recent patents (62,63). The process converts an a2eotropic 2-propanol—water feed over a copper-based catalyst at 220°C and produces a product mixture containing 2-propanol (11.4%), acetone (52.4%), MIBK (21.6%), diisobutyl ketone (6.5%), and 4-methyl-2-pentanol (2.2%). 

Diisobutyl Ketone. Diisobutyl ketone (DIBK) (2,6-dimethyl-4-heptanone) is a colorless stable Hquid with a peppermint odor. Some physical properties are Hsted in Table 1. 

DIBK can be produced by the hydrogenation of phorone which, in turn, is produced by the acid-catalyzed aldol condensation of acetone. It is also a by-product in the manufacture of methyl isobutyl ketone. Diisobutyl ketone ( 1.37/kg, October 1994) is produced in the United States by Union Carbide (Institute, West Virginia) and Eastman (Kingsport, Teimessee) (47), and is mainly used as a coating solvent. Catalytic hydrogenation of diisobutyl ketone produces the alcohol 2,6-dimethyl-4-heptanol [108-82-7]. 

The older methods have been replaced by methods which require less, if any, excess sulfuric acid. For example, sulfonation of naphthalene can be carried out in tetrachloroethane solution with the stoichiometric amount of sulfur trioxide at no greater than 30°C, followed by separation of the precipitated l-naphthalenesulfonic acid the filtrate can be reused as the solvent for the next batch (14). The purification of 1-naphthalenesulfonic acid by extraction or washing the cake with 2,6-dimethyl-4-heptanone (diisobutyl ketone) or a C-1—4 alcohol has been described (15,16). The selective insoluble salt formation of 1-naphthalenesulfonic acid in the sulfonation mixture with 2,3-dimethyl aniline has been patented (17). 

Another solvent extraction scheme uses the mixed anhydrous chlorides from a chlorination process as the feed (28). The chlorides, which are mostly of niobium, tantalum, and iron, are dissolved in an organic phase and are extracted with 12 Ai hydrochloric acid. The best separation occurs from a mixture of MIBK and diisobutyl ketone (DIBK). The tantalum transfers to the hydrochloric acid leaving the niobium and iron, the DIBK enhancing the separation factor in the organic phase. Niobium and iron are stripped with hot 14—20 wt % H2SO4 which is boiled to precipitate niobic acid, leaving the iron in solution. 

Dihydroxybenzene, see Hydroquinone Diisobutyl ketone Diisoctyl phthalate Diisodecyl phthalate Diisononyl phthalate Diisopropylamine... 

Dimethyl-4-heptanone (diisobutyl ketone) Dimethyl sulphate N,N-Dimethyl-p-toluidine Dimethylamine... 

Diethyl aniline, 54 Diethylcarbaniazine citrate, 54 Diethyl carbamyl chloride, 54 Diethyl chlorophosphate, 54 Diethylene triamine, 54 Diethyl ether, 54 Di(2-ethylhexyl) phthalate, 54 Diethyl ketone, 54 Diethyl-p-phenylenediamine, 54 Diethyl phthalate, 54 Diethylstilbestrol, 55 Diethyl sulfate, 55 Diethyl zinc, 55 Difluoromethane chloride, 55 Digitoxin, 55 Diglycidyl ether, 55 Digoxin, 55 Diisobutyl ketone, 55 Diisopropylamine, 55 Diisopropyl ether, 55 DIKAMIN , 2,4-D, 55 DIKONIRT , 2,4-D, 55 Dimefox, 55 Dimethoate, 55 3,3 -Dimethoxybenzidine, 55 n,n-Dimethylacetamide, 56 Dimethylamine, 56 4-Dimethylaminoazobenzene, 56 Dimethylaminoethanol, 56 n,n-Dimethyl aniline, 56 7,12-Dimethylbenz[a]anthracene, 56 3,3 -Dimethylbenzidine, 56... 

If cyclic ketones are monosubstituted in the a-position, their rates of reaction decrease as compared to the rate for the parent ketone (9,41). More highly substituted ketones (e.g., diisobutyl ketone, diisopropyl ketone) can be caused to react using newer preparative techniques (39,43,44, see Section VII). Monosubstituted acetones often can give selfcondensation products, but the recent literature (13,39,43) contains reports of the successful formation of the enamines of methyl ketones. 

Dimethylhydrazine, see Unsymmetrical dimethyl-hydrazine 2,6-Dimethyl-4-heptanone, see Diisobutyl ketone ... 

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