Acetic decomposition

Carbon dioxide can form as a result of combustion of ethylene, acetic acid, or vinyl acetate. The 1,2 C-ethylene experiments provided evidence on the role of Au and KOAc and its influence over the formation of carbon dioxide in the process. COj would be a characteristic of acetate decomposition, while COj would be characteristic of ethylene decomposition. 

Similar calculations established that oxygen-assisted acetate decomposition was consistent with the experimental work of Davis and Barteau.46... 

AU the products resulting from acid-catalysed solvolysis of A-acetoxy-A-butoxybenz-amides in acetonitrile-water mixtures were derived from the A-butoxy-A-hydroxybenz-amide intermediate (103), which is itself an anomeric amide and is the amide equivalent of a hemi-acetal . Decomposition reactions of 103 under acidic conditions are presented in Scheme 20. 

Lithium aluminium hydride reduction of 235 followed by mesylation afforded 236. The latter was oxidized with osmium tetroxide and sodium metaperiodate to yield the cyclobutanone 237. Treatment of 237 with acid afforded in 48% yield the ketoacid (238), which was esterified with diazomethane to 239. The latter was converted to the ketal 240 by treatment with ethylene glycol and /7-toluenesulfonic acid. Compound 240 was reduced with lithium aluminium hydride to the alcohol 241. This alcohol had been synthesized previously by Nagata and co-workers (164) by an entirely different route. The azide 242 was prepared in 80% yield by mesylation of 241 and treatment of the product with sodium azide. Lithium aluminium hydride reduction of 242 gave the primary amine, which was converted to the urethane 243 by treatment with ethyl chloroformate. The ketal group of 243 was removed by acidic hydrolysis and the resulting ketone was nitro-sated with N204 and sodium acetate. Decomposition of the nitrosourethane with sodium ethoxide in refluxing ethanol afforded the ketone 244 in 65% yield. The latter had been also synthesized previously by Japanese chemists (165). The ketone 244 was converted to the ketal 246 and the latter to 247... 

Bell I. L. (1991) Acetate decomposition in hydrotherrtral solutions. PhD Thesis, The Pennsylvarria State University. 

The rhodium(II) acetate decomposition of ketodiazoamides 296 in the presence dimethyl acetylenedicarboxylate generates intermediate bicyclic lactams 297, which eliminate methyl (or phenyl) isocyanate with the formation of furan derivatives (82-86%) 298 (89TL4077 91JOC820). Using the same route, substituted furans 299 have been obtained by the rhodium-... 

A further isothermal study [30] confirmed the autocatalytic character of the nickel acetate decomposition. The variation with temperature of the rate of decomposition... 

Bell, J.L. (1991) Acetate Decomposition in Hydrothermal Solutions. Pennsylvania State University, Pennsylvania. 

Fig. 7. l/(ife b5 — A ) for p-nitrophenyl acetate decomposition is plotted vs. the reciprocal of the jS-cyclodextrin concentration (data from Fig. 6). From VanEtten, R.L., Sebastian, J.F., Clowes, G.A. and Bender, M.L. (1967) J. Am. Chem. Soc. 89, 3242, reprinted by permission.

Acetic acid decomposes on the clean surface at elevated temperature to produce gas phase CO2 and hydrogen and leaves C (henceforth Ca for adsorbed carbon) on the surface [6,7]. However, this carbon has a surprising property, that is, it can modify the reaction pathway on the surface, yet does not affect the activity for adsorption very significantly. The Ca forms a well-ordered c(2x2) structure which is identified by LEED. As shown in fig 2 the carbon acts as a poison in one sense and in one regime of temperature, that is, it deactivates the surface for acetate decomposition in such a way that the acetate TPD peak is shifted from 360-390K to 455K when the c(2x2) layer is preformed before dosing the acetic acid onto the surface. The overall reaction is -... 

Acetate decomposition has been examined experimentally on Pd(lll) [73, 94], Rh(lll) [95], Rh(lOO) [96], and Rh(llO) [96] at ultrahigh vacuum conditions. In a combined TPD and HREELS investigation on Pd(lll), Barteau and Davis [73] found that acetic acid weakly adsorbs and forms a series of catemeric structures at low temperatures. As the temperature is increased to 200 K, acetic acid decomposes to form acetate surface intermediates which are stable up to 300 K. HREELS data indicate the acetate intermediate is bound di-CT to the surface. Our DFT... 

To illustrate the multifunctional role of oxygen, we present two specific examples. The first system examines ammonia oxidation. In the second, we re-visit the acetate decomposition system on Pd(l 11) that was discussed earlier. 

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