Acetate, production

L. G. Ljungdahl and co-workers, CMA Manufacture (II) Improved Bacterial Strain for Acetate Production, Eiual Report, EHWA/RD-86/117, U.S. Dept,... 

Acetic anhydtide is a mature commodity chemical ia the United States and its growth rate in the 1970s and 1980s was negative until 1988 when foreign demand neatly doubled the exports of 1986. This increase in exports was almost certainly attributable to the decline in the value of the U.S. doUar. Over four-fifths of all anhydtide production is utilized in cellulose acetate [9004-35-7] manufacture (see Cellulose esters). Many anhydtide plants are integrated with cellulose acetate production and thus employ the acetic acid pyrolysis route. About 1.25 kg acetic acid is pyrolyzed to produce 1.0 kg anhydtide. 

A hst of world acetate and triacetate producers is given ia Reference 74. The combiaed annual world acetate production (filament, staple, and tow) peaked ia 1980 with 672,000 t, dropped to 574,000 t ia 1984, and rose to 731,000 t ia 1991. The United States accounted for ca 45% of the world total. Other principal acetate produciag countries iaclude the UK, Japan, Canada, Italy, and the former USSR. 

Another significant appHcation for amyl alcohols is for production of amyl acetates. Production of amyl acetates in 1987 is estimated to have been 4.5-5.5 X 10 t about 50% of the domestic demand is for lacquers (150). Union Carbide Chemicals and Plastics Company Inc. is the only U.S. producer. 

Zinc chloride is a Lewis acid catalyst that promotes cellulose esterification. However, because of the large quantities required, this type of catalyst would be uneconomical for commercial use. Other compounds such as titanium alkoxides, eg, tetrabutoxytitanium (80), sulfate salts containing cadmium, aluminum, and ammonium ions (81), sulfamic acid, and ammonium sulfate (82) have been reported as catalysts for cellulose acetate production. In general, they require reaction temperatures above 50°C for complete esterification. Relatively small amounts (<0.5%) of sulfuric acid combined with phosphoric acid (83), sulfonic acids, eg, methanesulfonic, or alkyl phosphites (84) have been reported as good acetylation catalysts, especially at reaction temperatures above 90°C. 

FIG. 13-80 Reactive extracting distillation for methyl acetate production, (a) Composition profile, (b) Temperature profile. 

Suspension polymerization produces beads of plastic for styrene, methyl methacrviaie. viny l chloride, and vinyl acetate production. The monomer, in which the catalyst must be soluble, is maintained in droplet fonn suspended in water by agitation in the presence of a stabilizer such as gelatin each droplet of monomer undergoes bulk polymerization. In emulsion polymerization, ihe monomer is dispersed in water by means of a surfactant to form tiny particles held in suspension I micellcsK The monomer enters the hydrocarbon part of the micelles for polymerization by a... 

Q Loss of a proton yields the neutral acetal product. 

The free HCl and Cl generated in the catalytic cycle produce environmentally harmful chlorinated by-products to the extent that more than 3 kg of HCl need to be added to the reactor per tonne of acetaldehyde produced to keep the catalytic cycle going. Modified catalysts such as ones based on palladium/ phosphomolybdovanadates have been suggested as a way of reducing byproduct formation to less than 1% of that of the conventional Wacker process. These catalysts have yet to make an impact on commercial acetic production, however. 

For the Cu(OTf)2-promoted reaction between ethyl diazoacetate and cinnam-aldehyde dimethyl acetal, products 143-145 account for only 35% the total yield. C/C and C/H insertion products 151 and 152 are obtained additionally in 49 and 14% yield, respectively154). It was assumed that the copper compound acts through Lewis-acid catalysis here, just as it is believed to do when orthoesters are used as substrates 160). According to this, catalyst-induced formation of a methoxy-... 

Another route to the diol monomer is provided by hydroformylation of allyl alcohol or allyl acetate. Allyl acetate can be produced easily by the palladium-catalyzed oxidation of propylene in the presence of acetic acid in a process similar to commercial vinyl acetate production. Both cobalt-and rhodium-catalyzed hydroformylations have received much attention in recent patent literature (83-86). Hydroformylation with cobalt carbonyl at 140°C and 180-200 atm H2/CO (83) gave a mixture of three aldehydes in 85-99% total yield. 

Lajoie SF, Bank S, Miller TL, Wolin MJ. 1988. Acetate production from hydrogen and [ CJcarbon dioxide by the microflora of human feces. Appl Environ Microbiol 54 2723-7. 

Reaction of glucose with methanol and gaseous HCl yields four acetal products, the a- and P-pyran-osides and a- and P-furanosides, which may be separated. The pyranosides are the predominant components, and the major product is the a-pyran-oside. This is perhaps unexpected, in that the P-pyranoside has ah its substituents equatorial. 

Pentandlol Is a mixture of d,l and meso Isomers and gives rise to two major acetal products, but at different rates.)... 

The established activity of ethereal a-C-H bonds toward carbene and nitrene insertion has evoked new applications for sulfamate oxidation [76-78] In principle, a C-H center to which an alkoxy group is attached should be a preferred site for amination irrespec-hve of the addihonal functionality on the sulfamate ester backbone (Scheme 17.20). Such a group can thus be used to control the regiochemistry of product formation. The N,0-acetal products generated are iminium ion surrogates, which may be coupled to nucleophiles under Lewis acid-promoted conditions [79]. This strategy makes available substituted oxathiazinanes that are otherwise difficult to prepare in acceptable yields through direct C-H amination methods [80]. 

The progress of the reaction is monitored by thin layer chromatography, eluting with ethyl acetate (product Rf = 0.06, visualized and developed using UV light and KMn04 respectively). 

Lead tetraacetate is used as a highly selective oxidizing agent in organic synthesis. This includes oxidation of glycols into aldehydes, preparation of cyclohexyl acetate, production of oxahc acid, and in structural analysis of sugars. 

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