Acetate, isobutyl

Ethyl acetate [141-78-6] is produced commercially by the Tischenko condensation of acetaldehyde using an aluminum ethoxide catalyst (60). The Tischenko reaction of acetaldehyde with isobutyraldehyde [78-84-2] yields a mixture of ethyl acetate, isobutyl acetate [110-19-0] and isobutyl isobutyrate [97-85-8] (61). 

In the case of low temperature tar, the aqueous Hquor that accompanies the cmde tar contains between 1 and 1.5% by weight of soluble tar acids, eg, phenol, cresols, and dihydroxybenzenes. Both for the sake of economics and effluent purification, it is necessary to recover these, usually by the Lurgi Phenosolvan process based on the selective extraction of the tar acids with butyl or isobutyl acetate. The recovered phenols are separated by fractional distillation into monohydroxybenzenes, mainly phenol and cresols, and dihydroxybenzenes, mainly (9-dihydroxybenzene (catechol), methyl (9-dihydtoxybenzene, (methyl catechol), and y -dihydroxybenzene (resorcinol). The monohydric phenol fraction is added to the cmde tar acids extracted from the tar for further refining, whereas the dihydric phenol fraction is incorporated in wood-preservation creosote or sold to adhesive manufacturers. Naphthalene Oils. Naphthalene is the principal component of coke-oven tats and the only component that can be concentrated to a reasonably high content on primary distillation. Naphthalene oils from coke-oven tars distilled in a modem pipe stiU generally contain 60—65% of naphthalene. They are further upgraded by a number of methods. 

Some commercially important isobutyl derivatives include isobutyl acetate, employed as a replacement solvent for -butyl acetate zinc dialkyldithiophosphate (ZDPP) lube oil additives isobutyl acrylate [106-62-8] and methacrylate [97-86-9] monomers isobutylamines and amino resins (qv). 

About 69% of the total 1988 U.S. consumption of isobutyraldehyde, went into the production of isobutyl alcohol and isobutyraldehyde condensation and esterification products. The other principal isobutyraldehyde derivative markets (as a percentage of total 1988 U.S. isobutyraldehyde consumption) are neopentyl glycol (15%) isobutyl acetate (6%) isobutyric acid (5%) isobutyUdene diurea (2.5%) and methyl isoamyl ketone (1.7%). 

Isobutyl isobutyrate, the Tischenko condensation product of two molecules of isobutyraldehyde, is a slow evaporating ester solvent that has been promoted as a replacement for ethoxyethyl acetate. Although produced primarily by the acetylation of isobutyl alcohol, some isobutyl acetate is produced commercially by the crossed Tischenko condensation of isobutyraldehyde and acetaldehyde. Isobutyl acetate [110-19-0] is employed mainly as a solvent, particularly for nitrocellulose coatings. 

The rate of solvent diffusion through the film depends not only on the temperature and the T of the film but also on the solvent stmcture and solvent-polymer iuteractions. The solvent molecules move through free-volume holes iu the films and the rate of movement is more rapid for small molecules than for large ones. Additionally, linear molecules may diffuse more rapidly because their cross-sectional area is smaller than that of branched-chain isomers. Eor example, although isobutyl acetate (IBAc) [105-46-4] has a higher relative evaporation rate than -butyl acetate... 

Acetate Esters Methyl acetate Ethyl acetate Propyl acetate Isopropyl acetate Butyl acetate Isobutyl acetate Amyl acetate... 

Isoamyl acetate Isoamyl alcohol Isobutyl acetate Isobutyl alcohol Isophorone Isopropyl acetate Isopropyl alcohol Isopropylamine Isopropyl ether Isopropyl glycidyl ether Kaolin Ketene... 

M Preparation of isopropyiidene peniciiiamine hydrochioride To the filtrate obtained In step (b) is added at 20°C to 25°C a total of 85 g of hydrogen sulfide. The precipitated HgS is filtered off and the filtrate is concentrated under reduced pressure to a volume of 200 to 500 ml. Following e polish filtration, the product-rich concentrate is mixed with 1.5 liters of isobutyl acetate. The mixture is refluxed at about 40 C under reduced pressure in equipment fitted with a water separation device. When no further water separates, the batch is cooled to 30t and filtered. The reactor is washed with 1 liter of acetone, which Is used also to wash the cake. The cake is further washed with 200 ml of acetone. The acetone washes are added to the isobutyl acetate filtrate and the mixture is refluxed for 20 to 30 minutes. After a holding period of one hour at 5°C, the crystals of isopropyiidene penicillamine hydrochloride are filtered and washed with 200 m of acetone. On drying for twelve hours at 25°C this product, containing 1 mol of water, weighs about 178 g (73%). 

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